Garden Answers

Shade and Ornamental Trees

Winter tree wrapping?
Outdoor Palms?
Pine Disease/Pest?
How long to keep a tree staked?
Foamy white ooze on a Globe Willow?
Dead primary tree leader?
Buried tree trunk?
Watering Aspens?
Good fast-growing shade tree?
Roots pushing up through the surface?
Aspens losing leaves?
Correct a leaning tree?
Peeling bark on a Sycamore tree?
Oozing on an Ash tree?
Mulch around base of the tree?
Pruning an Oak tree (bush)?
Planting trees and shrubs in September?
Saving a tree with a split trunk?
What to do with suckers?
Success of Royal Empress tree here?
Stale-beer-smelling foam on a Willow?
Wrap a tree trunk?
Watering in Winter?
A good shade tree?
Leaves with brownng edges?
Yellow maple tree?
What to do for young trees in Winter?
Shade tree and evergreen borers?
Fertilizing trees and shrubs?
When to use dormant oil spray?
Strange bumps on an Aspen tree?
Can I get some tips for transplanting trees?
Can a tree be too close to the house?
"Tobacco juice" running down an Aspen?
Bark falling off a Maple tree?
What is causing this rust color on my little trees?
How can I make sure that my maple has enough iron and acid?
Ash tree diseases/pests?
When is the best time to plant a tree in this area?
Is there any danger in topping trees?
What can you use to prevent crabapples from growing?

Question: Why do I see some trees wrapped through the winter? Do I need to wrap mine?

Answer: The tree wrap you've noticed is used to prevent what's called winter sunscald on younger trees. Younger or thin-barked trees (such as maple and ash), especially those planted with a southern exposure, suffer from the day-to-nighttime variations in temperature. Tree wrap reduces the heating effect that leads to sunscald damage. Begin at the base of the trunk and overlap the wrap winding up to the first or second set of branches. I usually tell folks to wrap in November and leave it until April to provide maximum protection. Do this for the first two or three winters you have the tree. After that, the bark is generally thick enough to not need the wrap.

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Question: I have a palm in the house that is about 5' tall or so. Last year I read about the man that was growing them outside. Is there any way I can move my palm outside without killing it?

Answer: It depends on the palm. There are only two palms that are, at best, marginally hardy here. Windmill Palm (Trachycarpus fortunei) and Mediterranean Fan Palm (Chamaerops humilis) are the two types that have a chance outside. Any other palm is no where near hardy enough to survive our winters. These two types of palm are not often sold as houseplants. If you have one, you might give it a try. Plant it later in the spring when the danger of frost has passed, and put it in a warm, sunny area with a southern or western exposure. You'll have a better chance of getting them through the winter if you plant them next to the house as that will help moderate winter time temperatures. Hope this helps.

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Question: I've been hearing about a (disease?) that's killing off pine trees in Southern Colorado and was told to spray my Austrian Pines and Pinyon. Is this accurate? If so, what should I use?

Answer: Actually what you've been hearing about is an insect, not a disease. The "plague" that's about to descend on us is a little bark beetle called the Ips Beetle. We've always had these little guys around, but the native Pinyon Pine throughout the 'West have been stressed in the past several years due to drought, and the beetle has become epidemic. This outbreak started in New Mexico and has been moving northwards for the past couple of years. The worst of it reached the Uncompahgre plateau up on Glade Park last year, and we're waiting to see how it will affect us here in the valley this year.

Ips Beetle is a small black beetle, about the size of a grain of rice. The problem is not their size, it's their numbers. Pinyon Pine that are under stress emit chemical signals that actually attract these little guys. Once a beetle has found a susceptible tree it in turn secretes more chemicals that attract even more beetles. They overwhelm the tree due to sheer numbers. They tunnel under the bar, disrupting and killing the vascular tissue of the tree. In addition, they can spread a fungal disease called Blue Stain that will kill the tree regardless of what the beetles do to it.

Having painted this bleak picture, all is not lost. First and most importantly, do the best job that you can keeping your Pinyon happy and healthy. Water them deeply, but infrequently. Avoid the temptation to overwater them. Pinyon generally don't need a lot in the way of fertilizing. Secondly, we're recommending that anyone who has a pinyon spray them this year or risk losing the tree. Normally, we wouldn't worry about well established, healthy trees, but with the numbers of beetles in this epidemic, they're even overwhelming healthy trees that we wouldn't have considered to be at risk in years past.

Here's how the spray schedule works. First, use a Hi-Yield 38 Plus spray. It's important that the insecticide be that strong. There are weaker solutions out there, but they won't protect your trees like the 38% will. Also, don't confuse Permethrin with Pyrethrum. Though they are related chemicals and sound alike, they are vastly different in the job that they'll do. Second, you'll need to spray three times a year. The first spray is April 1. The second spray is July 1, and the last spray is October 1. If you have missed a spray date, you should definitely go ahead and do it now.

Lastly, make sure that you do a good job spraying the trunk and main branches of your tree. The spray needs to coat the trunk well. A light misting over the outside of the tree won't do the job! There you go, hope all this helps.

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Question: I forgot how long you should keep just planted tree staked. One year? And when would you recommend using the Bayer Advanced Garden insect control after planting ash trees?

Answer: I like to leave the stakes on a tree for one year more or less. If you leave them on too long, the tree can actually become somewhat dependent on them and not develop the strength it needs to stand on its own.

As for the Bayer, you can apply that product anytime. There really shouldn't be any problems with a newly planted tree. One little bit of advice about this product. There are two main insect problems we worry about in ash trees: Ash Borer and Ash Aphid. The Bayer will work WONDERFULLY on the aphid, but we're finding that it doesn't do well on the Borer. There are preventative sprays, using other products, that you can use for the borer. The most important thing to remember about borer is that they are far more likely to be a problem in trees that are weak and under some sort of stress. Keeping your tree as healthy and happy as you can make it is the best prevention.

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Question: I have a young globe willow in my backyard that is sprouting wildly all over the trunk, AND I noticed a few days ago that there are two spots on the trunk that are oozing a foamy white substance that is running down the trunk. What is going on with the ooze and what do I do about the sprouts? Your advice would be much appreciated.

Answer: It's pretty typical for willows to sucker on their trunks, especially when they're young. I pull off the sprouts as soon as I see them. If they get too big, cut them off close to the bark with hand pruners. The tree will usually persist in doing this for a couple of years. Just keep at it and don't let those suckers remain and grow into something bigger. The tree will eventually give up trying to grow suckers on the trunk.

You don't want to let those suckers remain for a couple of reasons. First, suckers tend to be too low to the ground for most people's taste. Contrary to what some people think, that branch will not grow up higher with time. If the branch is four feet of off the ground now, in ten years that branch will still be at four feet, just a lot thicker and heavier. Low branches will prevent you from walking under the tree, make mowing difficult, and make growing grass under the tree almost impossible. The second reason is that a sucker-type sprout is usually weakly attached to the trunk and prone to breaking in a storm or late snow in the spring.

The white foamy stuff coming out of the trunk is a disease called Frothy Flux. It's caused by a yeast-like organism that ferments the inner bark of the tree. If it's not too pervasive, you can try cutting out the infected bark tissue. First mix up a bucket of 10% bleach water (one part bleach in nine parts water). Use a strong, sharp knife to cut out the infected bark. Dip the knife blade in the bleach water to disinfect it after every cut to prevent spreading the disease. Cut the bark down to hard wood. Be sure to cut out any discolored bark. Once you've got it down to the wood and all cleaned out, soak the open wound with the bleach water. At this point, leave the wound alone. Don't paint, cover or wrap it. Leave it open and exposed to the air. Dryness is your friend here. Keep an eye on the wound. If you get some foaming ooze at the edge of the wound, just repeat the process.

You don't want to remove more than one half of the circumference of the bark on a stem when you're cutting out the bark. Cutting off more than that will do more harm than good. If the infection requires you to cut off more than half, you're better off to remove the branch completely, or just leave the tree alone to fend for itself. Actually, I've seen willow and frothy flux sort of coexist for years. The disease never really goes away, it just fades in and out of the picture. The important thing is to keep your tree as healthy and happy as you know how to make it. Water the tree deeply, but don't keep it wet all the time. We tend to think that Willows need lots and lots of water, but they withstand drought much better than we give them credit for. Let the soil dry slightly several inches down, and then soak it deeply again. Fertilizer is okay, just don't overdo it. Too much fertilizer can result in lank, weak, disease-prone growth. Hope all this helps.

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Question: I bought a hybrid poplar two years ago. It is growing, but only stands about 6 feet tall. I water it bi-weekly and water it thoroughly (about 1 hr. at a trickle) and fertilize it bi-weekly. Now, however, I've noticed that the top of the tree has no growth, and the bottom near the ground has lots of new growth and leaves. My question is: should I cut off the top part that is not growing and should I prune the bottom and cut off the leaves growing there? I have not done so, thinking that if the tree grows, this could be a branch of the tree. On the other hand, if I cut those off, will the tree grow and the strength go to the rest of the tree? Also, why isn't the tree growing better since it said it was a "fast grower."

Answer: I'm a little unclear about what's going on with the tree. If the top portion has no foliage at all, it is dead and should be cut off immediately. The growth that's lower down can be used to rebuild the tree from those sprouts. I'd set a stake next to the tree to tie the strongest and most vigorous sprout to, which will form the new trunk of the tree. Cut all of the other sprouts off so all of the energy of the tree goes into the one you want to grow.

The concern I have is what may have killed the top portion of the tree. The most likely cause is a fungal disease called Cytospora. If that's what did it, you want to be sure to cut well down on the tree to make sure that all of the infected tissue is removed. I would try to cut as least 12" below where you see dead, bare growth. Cut just above a strong, vigorous shoot. You're better off to cut back farther than to not cut enough off because if you leave any infected tissue, it will spread throughout the tree and kill it.

I wouldn't get too discouraged because Hybrid Poplars are very fast growing trees, and if you can get the tree over this bump in the road, it will develop into a nice big shade tree in no time.

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Question: We have a 10 year old Patmore Ash in the center of our gravel driveway. We recently had a brick planter built around it, approximately 3 feet high. We are going to fill it in with dirt and plant flowers around the base of the tree. Someone mentioned that it might hurt the tree if we add that much new dirt around the base of the tree. Is that true? Should we make a "dam" of some sort to keep the trunk of the tree free from new dirt?

Answer: Yes, it will hurt the Ash tree to pile soil up against the trunk of the tree. The trunk of the tree isn't made to be underground where it's moist all the time. We'll often see fungal rot problems get started in the trunk, leading to the death of the tree. The way to avoid the problem is to build a second circular planter inside the big one around the trunk of the tree. We call this arrangement a "tree well." Your planter will then be a donut instead of a circle. You want this inner wall to be a little ways away from the trunk of the tree so it has room to grow, and so there's enough room for good air circulation around the trunk of the tree.

Building this inner wall still doesn't get you out of the woods though. Any time you bury a significant portion of the root system of the tree any deeper than it already is, it's a problem. You see, roots need to breathe and they're used to getting oxygen down from the soil surface. If you put three feet of soil on top, those roots can't breathe any more (think of how you would breathe if you were buried under three feet of soil), they suffocate and die with dire consequences for the rest of the tree. It kind of depends on how big your planter is, but to be safe, I'd plan on providing an air circulation system under your planter to provide oxygen to the existing roots.

It's kind of hard to explain such an air circulation system in words, but I'll give it a try. What you have is an inner wall around the trunk of the tree and an outer wall of the planter. You want to run some 4" perforated PVC pipe on top of the ground from the trunk of the tree outward to the outer wall, and it needs to penetrate through both walls. If you were looking down from above it would be like spokes in a wheel. You'll need several of these pipes, and it probably would be a good idea to tie them together with cross pieces of pipe. That is, you connect the spokes together. The number of cross pieces will depend on the size of the planter. Once you have this "spider web" of pipe in place, cover it with 3/4" crushed gravel. Cover the gravel with weed barrier fabric, and then fill the planter up with a good planting mix.

I'm sure that this is more involved than you were planning on, but if you want to preserve the tree, you really need to consider doing this. If what I've been trying to say isn't clear, come on out to the nursery and I can sketch out what I'm talking about.

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Question: We have several Aspen trees in our yard which are 9 years old and established. How much water do they really need? Some of them seem to thrive on lots of water, getting really dark green and bushy. Other ones seem to get very yellow and lack of good foliage. We think we are watering them all about the same. We are on an irrigation system and are somewhat restricted on when we can water.

Answer: As for your Aspen, what they like is a deep, relatively infrequent watering. When you do water them, don't hold back! Give them a deep, thorough drink. I like to see the water penetrating down 12" to 18" into the soil (dig down or use a probe to check). Before you soak them again, the soil needs a chance to dry slightly. This goes back to the roots of the tree needing oxygen. Soil that is moist all of the time doesn't have much oxygen available for the roots so the plant suffers or it develops shallow, weak, drought-prone roots. How often you need to water depends on the weather, your soil type, topography, presence or absence of mulch layers, extent of soil preparation, etc.

I would say that most people water their aspens once a week to twice a month. While I would take this with a grain of salt, this is just to give you an idea where you should be. I know people who water more often and some who water less. Dig down 3-5" into the soil and feel the soil. There should be some drying to the soil, but not bone dry. Once you reach that point, you'll be able to develop your own watering schedule. Do it for a month, and you can schedule your irrigations in advance.

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Question: We had a huge globe willow in our front yard. The wind 2 days ago split it and we ended up having to cut it down. It was most of the shade for the house, so we are looking to replace it with something as fast growing as possible and would prefer it not to have berries, etc. as it is on our lawn. We also want a strong tree as it will be near our house. I heard you read a list on your program of shade trees that work well here. Any suggestions? I had heard about a fruitless Mulberry before as one option.

Answer: There're a number of choices you have before you. The first choice is whether to plant a good tree or a fast-growing tree. There really are no good, fast growing trees. Fast growing trees like cottonwood, poplar and like your willow do give quick shade (they typically grow 3' to 5' per year), but they have some drawbacks as well. They're susceptible to insect and disease problems, have weak branching (as you well know), tend to be messy, and can have shallow, aggressive roots. To tell you the truth, I consider Mulberry to be an "associate member" of this group. Mulberry is fast-growing and well adapted to this area, loving our hot summers, but is fairly susceptible to borers. You can spray for them (once a year or so in the middle of April), but most people try to avoid maintenance issues like that.

The "good" trees are things like Ash, Catalpa, Kentucky Coffee Tree, Hackberry, Honeylocust, Linden, Norway Maples, Oaks, Sycamore, and Zelkova. These trees grow a little slower, usually one to two feet a year. Some will be a little faster, some slower. Understand that there are no "perfect"
trees. Some may grow a little faster like Sycamore, but may have seeds to contend with. Others may be seedless, like Ash, but may have some problems with insects. Some may be tough, hardy and drought tolerant like Bur Oak, but grow more slowly. What we're encouraging people to do is plant a wide variety of different trees here in the Valley so we don't have so many problems with insects (like Ash Borer) and have a healthier urban forest.

I guess it boils down to what's more important to you and, of course, that answer is different for everyone. If you get a chance, stop by the nursery. We have photos of most of the trees we carry which may give you a better idea of what you need. Of course, one of our salespeople would also be happy to take you down and show you the trees so you can see what they look like, how they behave, and what appeals to you. Hope this helps.

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Question: I have a mature Silver Maple in my lawn which provides great shade. However, the roots are pushing up along the surface. What can I do about this and does this mean that the tree will die?

Answer: There are certain trees which are more likely to have problems with surface roots than others. The most popular ones we have here in the valley include: Cottonwoods, Poplars, Willows, Silver Maples and to a lesser extent, Sycamores. They're all riparian trees which simply means that they are bottom dwellers-they prefer the moisture of a river bed and need more water than other trees might.

Unfortunately, we tend to make the situation worse by encouraging this shallow root development by our own watering habits. Most often we find this problem when any of these trees is planted in a lawn. When watering our lawns, we usually water the top 6-8" of soil and do so fairly frequently. Trees need much deeper watering (10"-12") and LESS frequently. In our primarily clay soils here, the soil can stay moist for longer periods of time. A continually moist area will cut down on the oxygen taken up by the roots. Tree roots are pretty smart and they'll grow where the water is, so if we've got water close to the surface, that's where they'll go! Of course, amending the soil does help cut our clay soil, but that's easier done when first planting a new tree; if the tree's already established, it's not easily be done at this point.

Okay, so what CAN you do? Well first off, DON'T cut the roots or shave off the tops of any poking through the lawn. All that serves to do is damage the tree and undermine its stability. You'll more than likely lose the tree (though it may take several years) in either of these cases. You do have a few options: First, you could just choose to ignore the roots. Work around them, watch your mowing and foot traffic, trying to avoid nicks and dings on any protruding roots. If that presents a problem, try using Killzall around the base of the tree out as far as the surface roots. That will kill off all the lawn, but you shouldn't need to have a mower going over those roots. Lots of folks will put down a layer of bark mulch which looks nice and helps maintain moisture, or plant some shrubs to cover or screen the area.

Many people will place soil on top of the roots to cover them. That can work, but it's a several-year process if you're going to do it properly. What you need to do is GRADUALLY bring the level of the soil up so that it actually covers the protruding roots. This involves adding 1" of soil in the "basin" PER YEAR until it is level with (and then begins to cover) the roots. (What I'm calling the basin is lower area around the tree between the protruding roots.) Of course, the roots will continue to grow in diameter too, so this is something you'll need to keep an eye on over the years. If you haven't cleared the area of lawn, the grass may actually continue to come through what you're adding since it's such a small amount of soil at a time. If it doesn't, you'll need to reseed the area if you're including it as part of your lawn.

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Question: We purchased a home this spring that has 18 aspens around the perimeter of the backyard. Two of them appear to be distressed and we're not sure what to do. The leaves are turning yellow, drying up and falling off. All of the trees are watered from a drip line for 15 minutes, twice a week. We also give them a good "soaking" on occasion. Please advise if there is anything we can do to save these trees. My fear is that it's some kind of disease or bug infestation that could move onto the remaining trees.

Answer: My biggest worry is a fungal disease called Cytospora canker. This is a disease that we've fought in aspen forever. It has traditionally attacked trees that are weak and under stress. For most people, that meant neglected trees; young, newly planted trees, or old trees approaching the end of their life span (twenty to thirty years here in the valley). However, the past couple of summers I've noticed that more "middle aged" trees are succumbing to the disease. These seven to fifteen year old trees are normally not at risk for cytospora. I'm not sure of why this is happening, but I do have a theory, for what it's worth. The past two summers have been unusually hot and dry which aspen don't really like. They're happier up at 10,000 feet where it's thirty degrees cooler and it rains most afternoons. I wonder if this weather has pushed some trees over that "line of stress" making them susceptible to Cytospora.

Anyway, if in fact, your tree has the disease, there's really nothing that you can do directly. Fungicide sprays don't work on this monster. The truth is that a tree infected with cytospora almost always dies. All you can do is to make the tree as happy and healthy as you know how. Sometimes, the tree can fight off the disease and recover. Make sure that it's getting a deep watering (at least 12" down) when it's watered, but that it doesn't stay wet all of the time. The soil needs a chance to dry slightly before you soak it again. From what you've told me, I'd suggest that you run the emitters longer (an hour or more, depending on the size of the emitter), but do it less often. Most people soak their plants once a week to twice a month, though your situation may necessitate a different schedule.

I wouldn't fertilize it anymore this year. You want to feed aspens lightly. Too much fertilizer results in lank, weak growth.

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Question: I have a tree that is four years old, it is leaning a little; is it too late to correct the leaning?

Answer: It's probably a little late to make any significant changes. The reason is that by now, the tree should be well-anchored, and you won't be able to pull it straight. If the tree is still somewhat loose, you could straighten it and restake it (though I'd be a little concerned that it hadn't anchored itself by this time). If the trunk is straight and the tree is leaning, then putting a long, stout bamboo stake alongside the trunk would help.

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Question: A while back you wrote about a Gro-Low Fragrant Sumac. I am very allergic to the Sumac trees growing in my neighborhood; they make me sneeze and the oil from the plants gives me skin rashes. On my tube of cortizone crème which I use to relieve skin rashes it mentions 'poison sumac.' Are all sumacs poisonous?

Answer: The information on your cortizone crème is talking about a specific species of Sumac that's similar to Poison Ivy. If you brush up against it, you break out in a rash that itches like crazy (believe me, I know! I got into some while backpacking in college). The ornamental species of Sumac (like Gro-Low) don't cause this reaction in most people. Apparently, you're more sensitive than most folks. Hope this helps.

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Question: I think my sycamore tree has borers. The leaves are fine, but the bark is peeling off in big pieces all over my yard. What's going on and how can I stop it?

Answer: Though I can understand your concern, the peeling bark isn't really anything to worry about this time of the year. Sycamores tend to "shed" their outer bark as part of their growing process. While it can make a real mess as it occurs, it doesn't damage the tree and actually adds to the overall beauty of the trunk as it matures. The shedding bark actually adds to the ornamental quality of the tree.

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Question: I have noticed that there are two or three spots on the trunk of my Summit Ash that are oozing. I am wondering if this is perhaps the ash borer that I have heard about and is it something that I should be concerned about? If so, what do I need to do to correct the problem now before it gets out of hand and kills the tree?

Answer: The oozing is probably caused by Ash Borer damage. There are a couple of other possibilities, but they are pretty rare. There really is nothing you can do right now except to take as good care of the tree as you can. Make sure that the tree is soaked deeply and thoroughly, but then allowed to dry slightly before soaking it again.

There is a spray treatment that's very effective in controlling this pest, but timing is critical. We recommend you spray the tree with a solution of 38% Permethrin in mid April next year. You want to coat the bark of the trunk and all of the branches 1.5" in diameter and larger. That means spraying well up into the tree. If the tree is pretty big, you may have to hire a spray company to do it for you. One good spray should be enough to protect the tree for a year.

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Question: I have roughly 2 inches of mulch covering the ground around my young Cottonwood tree. I originally put the bark down to help hold the moisture. The soil is pure sand. But the tree has not grown at all since the initial spring growth and I'm beginning to think that the bark is not good for the tree.

Answer: Leave the bark there. It really is helping the tree. It helps hold water in the soil, keep the soil cooler during the summer (which the roots like), and keeps the weeds down. The lack of growth this first year is not unusual. Most plants don't do a lot of growing above ground that first year (and occasionally even two). They're putting their energy below the ground, rooting out and establishing themselves in your yard. Once they've done that, they should begin normal growth. Make sure that the tree is getting what it needs. Mostly, that involves watering the tree properly. Make sure that it's well-soaked, but not kept constantly wet. In your sandy soil, you'll have to water more often than most of us, but it's
still a good idea to dig down and check the soil moisture. Also, make sure that the tree is watered well out around the trunk. It's amazing how far and how fast roots spread out. Don't fertilize the tree now. I don't like to do that this late in the season. You could fertilize it in April next spring. Hang in there, I'll bet it will bust out next spring. Hope this helps.

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Question: We have an Oak bush (not tree). It's been planted for nearly 3 years. It's getting tall, and a bit busy at the bottom; it even has acorns on it this year. Really enjoy it. I'm wondering if I should prune or trim it in anyway or just let it do it's own thing?

Answer: I wouldn't do anything to your Oak Bush! It's common for plants to be a little gangly or misshapen when they're young (kind of like teenagers!), but they'll shape up in time. Be patient and continue to enjoy it!

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Question: Can you tell me how to definitely distinguish between a Russian Olive and a Buffalo Berry. We have one or the other in our yard - my wife insists that it is a plant she bought and planted last spring. It sure looks like Russian Olive to me. Thanks for your help.

Answer: Actually, differentiating between the two is a little difficult, and they often get mixed up. Here're some things to look for: On the Buffaloberry, the leaves are opposite, that is, they occur in pairs on the stem. Russian Olive leaves are alternate. The leaves on a Russian Olive are usually longer (3"-5") than Buffaloberry (1"-3"), and they are narrower than Buffaloberry. The older bark of a Russian Olive is smooth and shiny brown in color, while Buffaloberry is grayish and peeling as it gets older. Russian Olive gets bigger (15'-25' tall) than Buffaloberry (6'-15' tall). Finally, the fruit is different. On Russian Olive it's a yellowish green and covered by dry, silvery scales while on Buffaloberry the fruit is smooth skinned and a reddish orange color. All that aside, the most telling characteristic is that you bought it last spring. That makes it a Buffaloberry. Russian Olives were placed on the noxious weed list three years ago and it's illegal to sell them in the state of Colorado. Hope this helps.

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Question: Is it okay to plant trees and shrubs in September?

Answer: Now is an AWESOME time to plant trees, shrubs, and evergreens! Many folks actually prefer planting in the fall. The cooler temperatures and warm ground are great for allowing plants to get a good start on root development and getting settled in before the winter. That way, they can often take better advantage of the flush of spring growth next year. If you're not ready to plant now, any plant that's in a container is okay to plant almost year-round (as long as the ground is workable) here.

Be sure to water any plants that you plant throughout the winter (this is good advice whether you planted in April or October). We recommend watering newly planted trees and shrubs every three to four weeks through the winter. Use your judgement to tailor your watering schedule. If the weather's especially warm and dry, you'll need to water more often. If we have lots of moisture or snow cover, you can suspend the schedule until it dries out, and then start in again. Don't forget to think about watering in November and December. Plants can dry out then. Many people don't think about winter watering until after the first of the year, but lots of damage can occur before then if you're not careful.

Another good reason to plant in September is that most of our new stock are ready to go now. We have a beautiful crop for next spring, but you can get your pick now! (Sorry for the advertisement, but they really do look good!).

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Question: My tree has split and I'm hoping it can be saved. It's a young tree that was planted last year and has grown phenomenally since it was planted. It's shaped like a "Y" with two main stems coming from the trunk close to the base. I hope to be able to save the split portion.

Answer: I wish I had some better news for you. It sounds as if your tree has two co-dominant stems instead of a single central leader. When a tree splits like that, you generally have to remove one of the two branches that have split apart. The narrow crotch angle between those two stems forms a very weak area that is prone to splitting (as you very well know). When you pull the tree back together and let it heal, the two stems will often reconnect, but that fundamental weakness remains. The problem only gets worse as the tree grows and those stems get larger and heavier with more foliage. The best long term fix is to cut off the stem that seemed to pull away from the other. Usually, one of the stems will remain basically upright and the other will pull away. I know that that is hard to do, but with a young tree like yours, it will heal over the damage and replace the lost stem in no time.

There are options to bolt or cable the tree together, but these are more of a "band-aid" fix than a fundamental correcting of the problem. Again, with a young tree, it's best to cut off one of the stems. When you cut off the stem, you want a nice clean cut. Some folks like to use pruning paints on the open wound, but I don't usually recommend it. Just leave the wound open to the dry air, and the tree will heal itself up.

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Question: Could you tell me what I can do to get rid of suckers? I have cut them off and would like to know what I can put on them to stop the re-growth.

Answer: Suckering is just an individual characteristic of certain trees. There are some trees that will always sucker out away from the tree, popping up all over the yard. Aspen and some of the Poplars are like that. Other trees, such as Chokecherries, have a tendency to want to always sucker right at the base of the trunk. This type of plant really wants to grow as a large shrub or a small, multi-stemmed tree; we try to force it to grow as a single stem trunk.

Other trees will occasionally sucker at the base. Apple trees are probably the best example. Many Apple trees grow fine with few, if any, suckers while others sucker and sucker and sucker! This often goes back to the type of rootstock that the tree was grafted on. Again, it’s connected to the individual characteristic of that plant; certain rootstocks have a bad tendency to sucker a lot.

Having said all that, most plants rarely, if ever, sucker. When they do it's usually in response to a wound to the roots or perhaps something that's damaging the top of the tree. If there's some injury to the trunk, whether due to physical injury or some insect or disease problem, it's normal for the tree to push out suckers below this injury, even suckers from the roots.

The tree is trying to heal the injury or bring back the "root to shoot" balance. You see, the roots and the top of the tree need to achieve a balance. The top needs the roots to absorb water and nutrients, while the roots need the foliage to manufacture carbohydrates through photosynthesis which feeds the roots, and enables them to function as they should. If some injury occurs to the tree disrupting this balance, the tree will work to restore it by growing new shoots to replace lost ones.

As long as your tree is happy and healthy, the suckering that you're seeing is probably just part of the nature of that particular tree. Most people just keep cutting the suckers off. An alternative is a relatively new product out called Sucker Stopper. It's manufactured by Monterey Lawn and Garden Products. We don’t have a lot of experience with this product, but it sounds like it may help us a lot with this problem.

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Question: I would like to know how a Royal Empress Tree would do here in the valley.

Answer: Empress Trees (Paulownia tomentosa) will grow here in the valley. We used to sell them several years ago, but had trouble selling them, so we stopped growing them. I've seen some nice ones in Fruita that are probably fifteen years old. They are related to Western Catalpa. They have very large, heart-shaped, fuzzy leaves, and they grow quite quickly. They have pretty purple flowers in cone-shaped clusters at the tips of the branches, though they don't seem to bloom consistently. They set their flower buds in the fall for the following year, and they can freeze off, though I have seen a few with some blooms.

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Question: I'm interested in buying a tree that goes by the name Sorb Tree or Rowan Tree? It has reddish-orange berries on it. Can I get this from you or someone in town?

Answer: A Rowan Tree is also known as a Mountain Ash. The botanical name is Sorbus aucuparia (I'm guessing that's where the "Sorb Tree" name cam from). We carry a couple of varieties of Mountain Ash. 'Blackhawk' Mountain Ash has orange berries in the fall, and 'Cardinal Royal' Mountain Ash has red berries.

After pouring through several gardening books, I have found a tree called the Pissard's purple cherry, or the Pissard's purple plum cherry tree that I really like. I couldn't find it on your website. Is this something that you can order or can you direct me to where I could purchase one?

A 'Pissard' Plum is an old, generalized term for the early purple-leafed plum trees. Mr. Pissard was the gardener to the Shah of Persia during the 1870's, and it was he who introduced the first purple-leafed plum to Europe. You don't see 'Pissard' Plums anymore. There has been a lot of breeding and selection work done in the past 130 years, improving the characteristics of the plant. Today, there are dozens of varieties of purple-leaf plum that have improved foliage color, longer-lasting color (the early trees tended to turn a bronzy-green in the summer), and improved vigor and disease resistance. We sell two varieties: 'Newport' and 'Thundercloud'. Newport is a rounded tree, growing to 20' tall and wide. It has reddish-purple foliage, and light pink (almost white) flowers in early spring. 'Thundercloud' is a little more upright growing and vase-shaped, getting to 25' tall and 18' wide. It has darker, purplish-black foliage. Its flowers are a pretty, clear pink. Hope this is helpful.

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Question: I think I have something on my Willow tree called Slime Flux. It smells like stale beer, foams and runs down the tree. What can I do for this? I did have it trimmed and thought we got all the branches. Guess not. It's back.

Answer: The first thing you want to do is to take as good care of the tree as you can. Slime Flux is a kind of funny disease. A strong, healthy tree can live with the disease for years. If the tree is weak, however, it can kill it off. Do make sure that the tree is watered well. Soak it deeply and thoroughly occasionally. Surprisingly, Willows generally don't want to be wet all of the time. Give the soil a chance to dry slightly before soaking it again. I also would NOT recommend fertilizing Willows a lot. Doing so usually stimulates a lot of lush, soft growth, which you don't want. Also, be sure to keep the insects under control. Willows are prone to a number of insects. You don't have to be spraying preventatively, but keep a close eye on the tree and when you see something crop up, jump on it quickly.

Now, having covered the basics, you can try to cut out the infected tissue if you want. Mix up a bucket of 10% bleach (one part bleach, nine parts water). Cut out all of the infected bark down to the hard wood of the branch. Dip your knife into the bleach after each cut so you keep the blade disinfected and don't spread the disease. The infected bark is usually discolored a little. Make sure you cut out all you can see. If you have to remove more than one half of the circumference of the bark from a branch, I would either sit tight and see if the tree can overcome the infection, or else remove that branch entirely. Cutting off more than that amount of bark will do more harm than good. Once the bark is removed, soak the open wound with the bleach water. Don't cover over the wound. Don't wrap it or paint it. Leave it open to the dry air. Keep an eye on the wound. Sometimes you miss a bit of the infection. If it starts to ooze again, just repeat the process by cutting out the infected bark and disinfecting the wound with bleach water. Hope this all helps.

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Question: We just planted a Sycamore tree this fall. It's staked, but someone told me I should also wrap the trunk. Is this right? If so, what do I use and how do I wrap it?

Answer: Tree wrap is used to prevent what's called winter sunscald on younger trees. Younger or thin-barked trees (such as Sycamore, Maple and Ash), especially those planted with a southern exposure, suffer from the day-to-nighttime variations in temperature. Tree wrap reduces the heating effect that leads to sunscald damage. You can get tree wrap at any nursery. Wrapping the tree is relatively easy. Begin at the base of the trunk and overlap the wrap winding up to the first or second set of branches. You can use a tack or staple to secure the loose end, or some weather-proof tape. I usually tell folks to wrap in November and leave it until April to provide maximum protection. Do this for the first two or three winters you have the tree. After that, the bark is generally thick enough to not need the wrap.

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Question: A friend recently told me that she "deep waters" her trees and shrubs once a month through the winter. I've never done that before (I'm new here) and thought that the rain and snow we get is enough. Now I'm not sure what I'm supposed to do!

Answer: Your friend's got the right idea. Most folks have been using their irrigation water to keep their plants happy, and once that's turned off for the year, they kind of leave things to nature. Though we've had some good rain this Fall, generally we don't get enough precipitation (in rain or snow) through the winter months to give plants sufficient moisture. That's where "deep watering" comes in. It's an individualized thing, but basically you want to water trees and shrubs deeply and infrequently (November through February), which means every three to six weeks depending upon the weather. What you want to do is to get the moisture down deeper into the soil without getting it waterlogged. I usually just screw on a round pattern sprinkler on the end of my hose and place it out near the tree. Turn on the water so it covers a circle 10' to 20' across, depending upon your tree (the bigger the tree, the bigger the area to water). I'll go inside and set the oven timer for an hour and let the water run. When the timer goes off, I'll move it around to the next spot that needs soaking. Be sure you only do this on a sunny afternoon when the air temperature is above freezing (which is what most of our winter days are like). Hope this helps.

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Question: What is a good shade tree for the Grand Valley? We're having our globe willow removed, because it is so big. We feel it might split and fall on our home or the house next door. Any suggestions?

Answer: Consider these popular shade trees: Ash, Honeylocust, London Plane Sycamore, Linden, Burr Oak, Western Catalpa, Hackberry, plus many others. In my backyard, I have several Honeylocusts, both 'Sunburst' and 'Shademaster.' I love the mottled shade they provide. Honey Locusts reach heights of 35 to 50 feet. For deeper shade, I have two London Plane Sycamores. They provide deep shade where hostas and bleeding hearts and hearty azaleas thrive. While they are sturdier trees, know that leaf fall is ongoing from fall through spring.

An increasing consideration when choosing a tree is diversity. Ash and Honeylocust have become increasingly popular over the last twenty years, so many have been planted. A large population of any one plant invites pest investations. For instance, we're seeing ever more Ash Borer and Leaf Hopper problems. Pictured here is a Linden 'Redmond' as an alternative selection. And there are tons of other great trees. Come in to see us. We'd be happy to aid you in your selection with our resource materials and a walk through our tree area. See our online Planting Guide for Shade Trees.

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Question: We planted an aspen clump last spring. The trees are growing just fine, but the edges of the leaves are turning brown. I'm afraid I'm going to lose my tree. What's going on?

Answer: Don't worry; what you're describing is leaf scorch, a common summer-time problem for aspen and maples in the Grand Valley, especially during record-breaking heat. Your aspen tree leaves are transpiring water faster than it's being replenished through the roots and stems. Leaf scorch is often a watering problem. Dig a small hole at the drip-line of the tree (an imaginary circle at the leaf line of the tree). The soil should be moist to a depth of 12" to 18". If moisture is adequate, your aspens may just be reminding you they're out of place in the valley. They prefer a cool and moist environment. On the other hand, if only the top 6" to 8" are moist, you have a deep drought problem. Water deeply-it will take several hours-with a hose end sprinkler, moving the hose around the tree at regular intervals. Repeat the deep watering every month or so.

Let me interject that over watering is just as harmful to a tree as under watering. If you find the soil is constantly wet when you dig down at the drip-line, reduce the frequency of watering. Check the moisture levels of the soil before watering again.

Leaf scorch can also be caused by anything interfering with the uptake of water by the roots, and the transfer of water through the trunk and stems. Look closely at the bark of the trunk from ground level up to the first or second branch. You're looking for anything unusual: discoloration, sunken areas, cracking and peeling bark, holes, etc. Borers and fungal canker diseases are also a possibility. If you do find something unusual, come in to Bookcliff Gardens.

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Question: I have a maple tree that turns yellow every year. What can I do to keep it green?

Answer: It sounds like you have an iron deficiency, which is a fairly common occurrence here in Western Colorado. Our soils generally have adequate amounts of iron, but when the pH is high (alkaline), it becomes insoluble and unavailable to the plant. To remedy the problem, feed your tree with chelated iron. A chelating agent is a chemical attached to the iron that keeps the iron available to the plant in our high pH soils.

Apply the iron in a donut-shaped area. The donut should be centered on a radius around the tree equal to the height. (If your tree is 20 feet tall, start the donut 20 feet away from the trunk.) The band of application should be 6 to 8 feet wide. Repeat the application in 4 to 6 weeks. The yellow leaves won't turn green this summer, but any new growth should be greener. Next year, apply the iron early in the spring just as the new leaves are emerging, usual mid-April. Repeat the application once or twice at 4 to 6 week intervals.

Iron can also be applied as a spray to the foliage of the tree where it is absorbed directly into the leaf. If you choose to spray, be careful! The iron will stain your house, patio, sidewalk, clothes, skin, or anything else it touches. Therefore, spray only on windless days. Soil applications are slower acting but longer lasting.

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Question: We planted several new trees this summer. Do they require any special treatment to get them through the winter?

Answer: Western Colorado winters tend to be sunny and bright and dry. Also, it's unusual for us to have a consistent snow cover. For these reasons our soils lose moisture and dry out in winter. Drought can harm or kill a plant as readily in January as it can in July. That's why it's ideal to water newly planted trees, shrubs, and established plants intolerant of drought (birches, maples, blue spruce, sycamores, and redbuds) regularly through the winter months.

Successful winter watering depends on good weather watching and some flexibility. In a typical western Colorado winter with lots of sunny days and little snow, plan on watering once a month. If our winter is extremely moderate with warmer and dryer days than normal, water every three weeks. If snow stays on the ground for a while, suspend the calendar. Snow acts like mulch, holding moisture in the ground. You may go 6 to 8 weeks until you water again.

To water in the winter, use a hose with a sprinkler. Water each zone around the tree or shrub until the soil is soaked (1-2 hours). The air temperature must be above 32° but early enough in the day so water can soak in before nightfall. Drain your hose and remove it from the hose bib, so it will be ready for the next watering.

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Question: What can I do about shade tree and evergreen tree borers? I really have a problem.

Answer: Wondering if you have tree borer problems, too? The symptoms of borer infestation are subtle. Sadly, it's dieback of limbs and branches that usually gets our attention. If you look closer, you'll see cracking and peeling bark on the trunk or branches. It's even possible to have malformed branches with sunken areas of bark. Look for sawdust from borer holes that catches in the bark or crotch angles as another clue. And don't forget to look for the holes. They'll vary in size depending on the type of borer.

It's almost time to start spraying, so it's good you're asking about borers. Use a hose end sprayer with Permethrin, starting the 15th of April. Repeat applications every 3 weeks until mid-June to July first. The specifics of application depend on the type of borer and tree, so it's best to come and see us at Bookcliff Gardens for the most effective recommendation. Also, borer infestations tend to be stress related problems, so good long term care of trees is the best solution. We can help you with that, too.

Pinon pine trees need to be sprayed on April 1st, July 1st, and October 1st. There's a new product on the market called 38 PLUS, with the active ingredient of permethrin, which is appropriate for this spraying pinon trees.

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Question: I fertilize my lawn regularly. What about my trees and shrubs? Do they need fertilizing?

Answer: Once a plant has been in the ground for a year or more, it needs to be fertilized regularly. There are several products to choose from: 1)Ross Fertilizer Spikes are just big hunks of slow-release fertilizer pressed into the shape of a spike. Drive the spikes into the ground at or just beyond the dripline-the imaginary line from the outermost leaves to the ground-of the plant. Folks like fertilizer spikes, because they give a nice, slow feeding all year with no repeat application necessary. 2) Bookcliff Gardens Choice Professional Turf Food is another way to apply a slow-release fertilizer but in granular form. Apply in a donut-shaped band starting at the dripline and out several feet. Do this twice, now and in June. For a twice-a-season fertilization treatment of your shrubs, sprinkle our Professional Turf Food around the shrub bed at roughly double the amount you would put on your lawn and water in well. Apply when ditch water becomes available and again in 6 to 8 weeks. 3)Miracle Grow provides a high-quality, soluble fertilizer that's fast acting, because it's absorbed through the foliage. A no-clog feeder makes it easy to apply, too. Miracle Grow must be applied at least twice a month. Your last application of fertilizer for trees and shrubs is mid-July.

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Question: Is it about time to spray with dormant oil?

Answer: As with most gardening tasks, I can't give you a specific date to spray dormant oil. It takes careful observation to find the right time. In general, however, the time to spray is from mid-February to mid-March, but it really depends on the weather. If temperatures are warm enough to encourage buds to open and reveal some green growth, it's too late to spray. The spray would damage the tender buds. But if those buds are closed up tight, go ahead and spray.

If you're unfamiliar with dormant oil, let me share with you this helpful tool for controlling insects and disease in your yard. Dormant oil is a great broad-spectrum treatment for problems that overwinter on the stems of plants. I'm talking about our mortal enemies: aphids, spider mites, some caterpillars, powdery mildew, leaf spots, and a host of others. If you had these problems last year, you can minimize the problem for this year with a little pre-emptive strike of dormant oil. Now, dormant oil won't eradicate the problem, but it will make it less noticeable or give those ladybugs a fighting chance against aphids.

Besides making pest and disease problems more manageable, dormant oil is a popular choice because it's nontoxic. Dormant oil is a high-grade mineral oil. When spayed on stems, it coats and suffocates insects, eggs, or spores while being safe for children, birds, and pets.

We have a new product this year called Bonide Dormant Oil Plus Lime Sulfur. This product combines two organic pesticides that help give great control of lots of pest problems, especially powdery mildew and spider mites. If you think you need this added boost, come in and talk to one of our nursery professionals. We'll recommend the right chemical for the job.

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Question: The branches of my Aspen trees are covered in bumps. What‘s going on? Will it hurt my trees, and how do I get rid of it?

Answer: First let me assure you that although it looks odd, it’s not something that’s hurting your Aspen trees. What you’re seeing is the home of a little guy called the Popular Twig Gall Fly. The adult is a small black fly. The female lays her eggs in a branch and secretes a chemical that causes that golf ball-like swelling. The eggs hatch out and the larvae live inside, feeding on the pulpy interior of the gall. In the spring, they make their way out of the branch (you might see tiny pinholes). Although they’re gone, the swelling will usually continue to grow for several years. While they’re kind of strange looking, once the tree is covered with leaves, they won’t be noticeable. The galls will eventually stop growing and as the branch continues to grow they’ll eventually be absorbed and disappear.

If they really bug you, you can try spraying the trees, but the difficulty is that the timing has to be perfect (catching the female before she lays her eggs) and the coverage has to be complete as they’ll find any spot not covered by a spray. Honestly, it usually doesn’t work well, and since they usually don’t hurt the tree, I’d just try to ignore them. Hope this helps.

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Question: Can I get some tips for transplanting trees?

Answer: This is a fine time to transplant Pine trees. Whenever we talk about transplanting, we’re talking about odds. Doing everything right at just the right time doesn’t guarantee success; it just gives you the best chance of success. Conversely, you can do everything wrong and be successful, it’s just that your chances of success are less than if you had done it right. Thsi needs to be done while the tree is in its dormant phase. Here’s how I would recommend doing it:

The first thing you want to do is to dig the hole in your yard where the trees are going to go. Have the holes ready so that your trees are out of the ground as little time as possible. Next, you want to dig as large of a soil ball around the plant as you can handle (remember you'll have to pick that up and carry it over to the new hole!). I would guess that for a 6’ tall tree, you will need a routable that’s at least 20”-24” in diameter. That’s going to be pretty heavy (a couple hundred pounds at least), but remember that the bigger the root ball, the better your chances of success will be.

It’s important to keep the root ball intact, don't let it crack or break apart. It's helpful to wrap the soil ball with burlap or an old sheet to help support it. You might even want to further support it by wrapping some chicken wire or wire fencing around the ball to help hold it together. Get it planted in the new hole and water it in well. After that initial watering has soaked in, give it a second soaking with a solution of Fertilome Root Stimulator. It has a rooting hormone in it that helps stimulate the formation of new roots and that's the name of the game at that point.

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Question: Also, is having the tree close to the house a problem?  I’ve heard that roots can choke and break pipes and waterlines. 

Answer: As far as your concern about planting your tree too closely to the house interfering with pipes and waterlines, we generally don’t worry about the roots of trees and shrubs bothering water pipes. The pipes are set deeper than the roots usually go. I have very rarely seen problems with sprinkler lines which are buried shallower. Problems are more common with polyethylene pipe (the black flexible pipe), though I’ve seen PVC (the rigid white pipe) have problems as well. Your Thundercloud Plum shouldn’t give you any problems; it’s mostly a problem with larger, more aggressively growing trees like Cottonwood, Mulberry, Maple, Willow and Honey locust.

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Question: My Aspen trees have what looks like "tobacco juice" running down the trunk. One area has a hole and the other has a crotch where a branch connects to the trunk. What is the cause of this and what can I do about it?

Answer: What you’re seeing is a pretty common occurrence in the spring. I’m asked about this problem a couple of times every day! Usually, this is nothing to worry about. Certain trees, Aspen included, are what we call “bleeders.” They tend to leak sap in the spring. The sap of Aspen trees is a dark, clearish, varnish-looking stuff. They bleed from wounds or other openings: bumps and bruises, scrapes, or especially where a branch was cut off in the past. This bleeding is variable. Some Aspen trees will bleed while others won’t and a tree may bleed one year but not the next. That’s pretty normal for them.

People often want to paint them, wrap them, or do something to stop the bleeding (like putting a bandage on a person’s wound). With trees, that’s really not necessary because the bleeding will stop later on in the spring and the tree will continue to grow just fine.

The best thing that you can do is to take a close look at where the sap is leaking out of the trunk. It doesn’t happen often, but sometimes borers can be the cause of such leaking. If that’s the case, you’ll usually see exit holes and/or sawdust mixed with the sap. Then I would recommend that you spray the trunk of the tree now with Permethrin to take care of the problem. There are other possibilities, but they’re pretty rare.

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Question: The bark on our maple tree has turned black, has woodpecker holes all over it, and the bark is falling off in large pieces. Where the limbs start, the bark is white and healthy, the tree leaves are all in full bloom and the tree looks perfectly healthy from the limbs up?

Answer: Wow, sounds like something weird is going on. The clues you gave about the woodpeckers and the bark falling off would definitely indicate borers in your tree. Borers are the larva of different insects that tunnel around under the bark, disrupting and killing the vascular tissues of the tree, causing dieback and death of the tree.  Sometimes they can structurally weaken the tree, making it more prone to wind breakage. These types of borers are almost always a stress-related problem. The long term solution to borer problems is to restore the tree to a healthy, robust condition.

Careful timing of insecticide sprays is an important component of successful borer control.  Once the insects are inside the tree, they are extremely difficult to reach with insecticides. What we try to do is to take advantage of their life cycle. Most of our shade-tree borers do their feeding damage during the spring, summer, and early fall. They usually pupate over the winter within the tree or underground. The adult borer (usually a moth) emerges in spring to mate and lay eggs. The adult is most vulnerable to insecticide sprays when outside of the tree. The best spray to use is 38% Permethrin. Spray the trunk and lower part of the main branches of the tree. The object is to wet the bark well. Spray the Permethrin once a year about April 15.

The fact that the tree is looking good up top is a good sign. What concerns me is that you seem to be saying that the bark is falling off all the way around the trunk of the tree. If, indeed, the bark is dead and sloughing off all the way around, the tree will die no matter what you do. If just a patch of the bark is coming off, then there is certainly hope for the tree. Since you’ve missed the window of opportunity to spray for the borers, all you can really do at this time is to take as good of care of your tree as you can. Be sure that the tree is watered deeply but not kept soggy wet all of the time. If you’re fertilizing the lawn, be sure not to use any Weed And Feed type fertilizers, as the herbicides in them can hurt your tree. Using a straight fertilizer, apply a little extra dose of the fertilizer under the canopy of the tree and be sure to water it in well right after you apply it.

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Question: Can you tell me what is causing this rust color on my trees? It started with one of these last week and has spread to the other two.

Answer: Without seeing the leaves, I'm going to have to speculate a little bit. A "bronzing" of the foliage during the summer is often due to a water imbalance within the tree. The most common cause would be watering problems. Either end of the watering spectrum can cause this--either not enough water or too much water. What you want to do is to soak your trees deeply and thoroughly when you do water them but then allow the soil to dry slightly before soaking them again.

I think it's helpful to do some digging down into the soil to see what's going on. Give your trees a normal watering, let the water fully soak in for an hour or two and then dig down at least a foot to see how deeply soaked the soil is. The soil should be "muddy wet" at least 12" down if not 18". If the water hasn't penetrated that far down, you need to run the water longer to get it down to that depth.

Next, you want to check how often you're watering. Wait a normal interval that you've been watering and dig down 4"-6". Check the soil at that depth. There should be moisture but there should be some drying evident as well. As one of our salespeople said last year, it should be "on the moist side of dry". On established trees (those in the ground more than two or three months), most people are giving them a good soaking once a week to twice a month. Now take that with a grain of salt. There are a lot of factors that can make that watering schedule different: the weather, your particular soil type, soil preparation (or lack of it), exposure, slopes, mulch layers (or lack of them), etc. The best thing you can do is to dig down and check for yourself to determine your own watering schedule.

There are other possibilities that might be causing this bronzing. Transplanting issues can be the culprit. If the tree was planted too deeply, there can be symptoms like what you're having. Also, newly planted trees sometimes have a difficult time coping with our heat and dryness during the summer because they are new and don't have an established, extensive root system to depend on. If that's the case, this is a temporary situation and will clear up in time. Just hang in there, water the tree properly and the problem will pass.

Occasionally, there are insect or disease issues causing the problem. Spider Mites would be the most common possibility. There is a group of fungi that are called “Rusts” that people often think are the problem, but that’s very rarely the case. Rust type fungi almost never occur here because they need high humidity to thrive. Either way, it would probably be best for me to see a sample of the foliage. Next time you’re in town, stop by with the sample and we can take a look at it. Try to keep the sample as fresh as you can by putting it in a zip-lock bag with a moist paper towel. This will help us determine just what may be happening to your tree.

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Question: I planted an Emerald Queen Maple that seems to be doing well so far. My neighbor, who removes hazard trees, told me that lots of maples are dying in the Grand Valley, and that they need iron and acid to survive. Is this true? How can I best insure that my maple doesn't become a casualty?

Answer: Your neighbor is partly right and partly wrong. Yes, Maple trees as a group do prefer a more acid soil environment than what we have here. Because of this, several Maple species like Sugar Maple and Red Maple tend to do very poorly here; that's why we don’t sell either of these.

There are, however, some other species of Maple that will do okay here. The most common one is Silver Maple. This tree has been grown for years here in the Valley pretty successfully, in fact, I have a great big one in my yard. Back East where the soils and climate are better suited for growing Maples, Silver Maple is considered somewhat of a "trash tree". It's fast growing but somewhat brittle with shallow, aggressive roots. While we don't seem to have a lot of problems with Silver Maples breaking, they do have those shallow roots.

We do see Iron deficiencies pretty commonly in Silver Maples here. It's mostly a problem out on the Redlands, and generally not as bad north of the Colorado River. Again, that goes back to Maples preferring a somewhat acidic soil. In alkaline soils, like we have, the Iron becomes less available resulting in the classic Iron Deficiency symptom of the leaf turning pale green or yellow while the veins stay green. Most people apply some Chelated Iron plus a nitrogen fertilizer in spring when the new growth is just coming out.

Another problem with Silver Maples is a disease called Verticillium Wilt. This fungus lives in the soil and occasionally decides to attack susceptible trees. Silver Maple far and away seems to be its favorite target here in Western Colorado. The fungus travels through the vascular tissues of the plant, plugging them up and slowly starving the plant, eventually killing it. It still only affects a small minority of the Silver Maples in the Valley, but it seems to be a problem that's here to stay, and once a tree has it, that tree is almost always doomed. This may be what your neighbor is talking about with all the Maples dying all over the Valley.

Having said all that, the other common species of Maple we grow here, Norway Maple, generally doesn't have the sorts of problems that Silver Maple has. Emerald Queen is a great variety of Norway Maple. I consider varieties of Norway Maple to be the best Maples for our area. They usually don't develop Iron Deficiencies the way Silver Maple does and are a much stronger, better branched tree. The down side to this plant is that it's slower growing than Silver Maple, but in the long run, your patience will be rewarded with a much better tree.

Good care is paramount to any tree's long term health and growth. As with all Maples, water it regularly. This group of plants is not particularly drought tolerant, so be sure to provide it with a regular supply of water. I'm not saying to keep it wet all the time! Soak the plant deeply and thoroughly when you do water but allow the soil to dry out a little before soaking it well again. Also be sure to water it occasionally over the winter. Fertilize the tree in the spring, usually the middle to the end of April. That combination of Iron and Nitrogen is important to maintaining a healthy Maple. I like using Fertilome Liquid Iron plus our Bookcliff Gardens Choice Professional Turf Food. Apply it out around the tree and water it in well. Hope this all helps.

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Question: What disease problems do White Ash have? Do they need any special kind of care?.

Answer: Honestly, we don't run into that many disease problems with White Ash. Most of our problems are with insects. There are two that I see most often: Ash Borer and Ash Aphid. The Aphid isn't that big of a deal. It causes a tight curling and distortion of the new growth of the tree in the spring. It's usually temporary and the tree pushes out new growth later on in the season. It's not life-threatening at all, it just makes the tree look a little funny and can stunt its growth. It’s easy to treat—we recommend using Imidacloprid. There are formulations that you spray on that give fast results or you can get formulations that you apply around the base of the tree. It takes longer to get rid of the Aphids, but it’s easier to do and it protects the tree for up to a year.

The Ash Borer is a more serious problem as it can severely damage and even kill a tree. It's important to remember that Borers are mostly a stress-related problem. They attack trees that are weak and under stress for one reason or another. Your best prevention is to make sure your tree is as happy and healthy as you can make it. There are sprays to prevent this problem. Check with your local Extension office or a good local independent nursery for any information on treatment options. Around here, we recommend a single spraying of the trunk and all branches bigger than 2" in diameter in mid-April with a solution of 38% Permethrin mixed at 4 teaspoons per gallon. Other than that, Ash are generally easy-to-grow, solid shade trees.

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Question: When is the best time to plant a tree in this area? 

Answer: If the trees are growing in pots, you can plant them just about any time you'd like. There's very little stress on the plant since you're not "messing" with the roots very much. Here in the Grand Valley, we'll usually plant up until the first or the middle of December. When the ground freezes up is when we'll stop. It's not that it's a bad time of the year to plant; it's just too much work to dig a hole when things are frozen!

Bare root plants should be planted in the spring as early as you can work the ground. Hope this helps.

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Question: I’m looking for information regarding topping off trees and if there are any consequences (diseases, etc.) when this is done?

Answer: Topping of trees is a BAD IDEA!!! There are all sorts of reasons to avoid having this done. As you know, topping is where people cut the main vertical stem and upper primary limbs on mature trees to stubs at a uniform height. In addition to trying to limit the size of a tree as your neighbors so “graciously” did for you, people often top large trees because they fear that the tree is getting so big that it might break and fall. Topping actually increases the possibility of that happening.

Here are several very good reasons why trees should never be topped. First, it reduces the tree’s food-making capacity. Trees require a large leaf surface area to provide food for maintenance and growth. Topping cuts off a major portion of the tree's food-making potential and depletes the tree's stored reserves in the branches that were cut off. You see, there’s a balance between the top of the plant and the roots. They need each other and sudden, significant changes in either can have effects on the other part. The top of the tree needs the roots to absorb water and nutrients as well as to anchor the tree to the ground. The roots need the top of the tree to manufacture carbohydrates through photosynthesis that the roots use to do their work. Removing a significant portion of the top of the tree through topping can lead to damage and death of part of the root system.

Second, topping stimulates undesirable "water sprout" growth. Topping a tree stimulates the re-growth of a dense brushy mass of unattractive, upright branches (water sprouts) just below the pruning cut. Water sprout re-growth is extremely vigorous. A topped tree will rapidly return to its original height, but will lack its original form. Topping will actually create a more hazardous tree in time. This water sprout growth is weakly attached to the main branch and is much more prone to wind or storm breakage. In addition, the large branch wounds left from topping are slow to close and therefore more vulnerable to insect attacks and fungal decay. An invasion by either pest can spread into the trunk, killing or weakening the tree.

The last reason not to top a tree is that topping disfigures the tree. Ugly branch stubs, conspicuous pruning cuts, and a broom-like branch growth replace natural beauty and form. It turns the tree into a freakish shadow of its former self. Topping can reduce the real estate value of your trees by 20% to 100%. A correctly trimmed tree increases in value at each pruning. If you want more information, our local Extension office has a page on topping trees. Go to www.coopext.colostate.edu/TRA/PLANTS/index.html#main.html.

The one hundred dollar question for you is what, if anything you can do about it. Well, if the trees are pretty old, there really isn’t much to do. You might consider hiring a consulting arborist. These people are trained to determine whether the tree can be saved or will develop into a hazard. I don’t know of any up your way, though there may be some. There are several down here who would travel to Aspen; you’ll just have to pay mileage to have the tree evaluated. They can also appraise the trees if you want to talk to your lawyer about compensation for what the neighbors did. If the trees are pretty young, the picture is not nearly so bleak. On young trees, this becomes a “heading back” type of cut and the tree will recover just fine from that. Hope this helps.

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Question: I was wondering what chemical would prevent a crabapple from bearing the fruit? A nursery once mention the use of the liquid seven, but that didn't make sense.

Answer: Actually the advice you got about using Sevin is correct. Spraying your tree at petal drop (when the tree is done blooming and the petals are falling off) with a solution of Sevin mixed with water at twice the recommended label strength will help the young fruit to fall off.

However, there are two problems with this. First, Sevin is especially toxic to bees and they will often still be visiting the tree during petal drop. We really don't want to hurt these guys, so that can be a little tricky.

The second thing is that there's a much better product out now that will do the job for you. We sell a product called Florel which contains a plant hormone called Ethephon. This will really do a much better job than Sevin. We recommend that you spray the tree twice, the first time at the beginning of petal drop and again about two weeks later. The product isn't perfect--there are years where it will eliminate 99% of the fruit but occasionally it might only eliminate 50%. On the average, I'd say it should get rid of 80% to 90% of the fruit. Make sure you do a good job covering the tree with the spray and your messy fruit problem should be much smaller.

The bad news is that you'll have to spray your tree every year, it only causes the fruit that's present at the time to drop off, it doesn't sterilize the tree. A more permanent, long term solution is a little more drastic, involving pruning the tree down with that old one-cut method right at ground level! You could replace it with another Crabapple, there are much cleaner varieties available today, there's even a fruitless one called 'Spring Snow.' Besides that one, we carry a variety of persistently fruited crabs that hold their fruit all winter long, providing food for the birds that graciously take care of the fruit for you!

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Bookcliff Gardens
(970) 242-7766
755 26 Road (North 1st at I-70) • Grand Junction, Colorado 81506
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