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September 2015



We planted a six-foot redbud tree two years ago. Now it is well established and growing taller while limbs are getting longer all the way down the trunk. We would like to limb it up so that it is more like a tree than a tall shrub. When is the best time of year to do pruning at the trunk?

Removing lower limbs can be done at any time of the year.  Just make sure you don’t remove more than one third of the growth of the tree.  Make nice clean cuts, and don’t use pruning paint or wound dressing.  A clean, smooth cut is what is most important.



November 2014

QuestionWhen is the best time to trim some limbs off of a maple tree that is about 4 or 5 years old? It needs a good shaping up.

Answer If you know which limbs you want to remove, go ahead and prune now. Often it is easier to see what needs to be done when there are no leaves on the tree.  If you are dead-wooding (removing dead limbs) you typically need to wait until they leaf out to know what is dead and what is alive.    Make sure you remove the limbs at the branch collar and make a nice clean cut.  No pruning paints or wound dressings are needed. 


January 2013

QuestionWe have a large magnolia tree at each end of the house and they have gotten too large and overhang the house. I had our other trees trimmed in September and the tree guy said not to trim the magnolias at this time. He said February was the right time for them and he could cut the tops off and trim them so they wouldn't be so large. What do you recommend?


AnswerMany magnolias were damaged with the recent snow storm, so you may have no choice but to start pruning. Normally, I would recommend waiting until after they bloom before pruning--May is the normal bloom period for a standard southern magnolia. I never recommend topping a tree, since it will cause the internal wood to decay and ruin the natural shape of the tree. If the height is an issue, you might consider replacing the magnolia with another tree. Standard southern magnolias can easily grow 60 feet tall by 30 feet or more wide. One pruning is not going to stop their growth. There are numerous dwarf magnolia varieties on the market that are better suited to a standard home landscape.

December 2012

QuestionIn the spring of 2010 I planted four Bradford pear trees. They are growing straight up; they don’t seem to be spreading out like I thought they should. Should I cut the tops out of them? If so, when should I do this?


AnswerTopping a tree is a practice that should NEVER be done to a tree you want to keep long-term. When you remove the entire top crown of a tree, you create internal decay in the tree. It will eventually put out more branches and look like a tree, but the damage done internally will last for a lifetime and makes the tree structurally unsound. However, you can remove certain branches and take the top buds off of each branch you leave, without removing the crown, and this will encourage branching. The top bud on each branch has dominance, and left unchecked, will grow straight and taller. Removing the top bud (or even going lower on a branch) will encourage lower buds to grow, which should start to give your tree a fuller top. Pruning done correctly will give you a fuller and healthier tree. Keep in mind that many ornamental pear varieties, particularly Bradford are very susceptible to storm damage, and they often have too many branches which cause them to resemble a lollipop on a stick and they break easily.

November 2012

QuestionWe have a 7 foot tall Japanese lace-leaf maple by our front door and another by the house. The one by the door I've kept somewhat thinned out and trimmed up so its graceful branches are visible. It's grown nicely and filled out in a pretty irregular branch style that I really enjoy. I thin out some of the tiny branches in the spring. The other maple has a rounded, helmet shape since I have left it alone. Is there a preferred way to let them grow? I have only seen my tree shaped like this and wondered if I am harming it. I would appreciate your thoughts on "do or don't" thin the branches.


AnswerFor the Japanese maple, there are many different opinions as to how they should be pruned. Many like them thinned out to expose their graceful branching. Others like the more natural shape of the tree, so I think it is your preference. I do not like to see them shaped into an artificial ball shape or topped, but thinning them out or removing wild branches is perfectly acceptable.

November 2012

QuestionSomeone told me last week that if you top a sweetgum tree it won't produce gumballs for 4 or 5 years. Is this true? I have a huge sweetgum tree in the backyard that my wife loves for the shade it produces, but I hate the gumballs I have to deal with all year long. I want to cut it down, but if topping it will stunt the gumballs, I'm willing to try that.


AnswerNot true, and very, very bad for the tree to be topped. Topping a tree leads to a hollow, unsafe tree so should never be done. Sweetgum balls can be a nuisance, but the fall color and the overall shade make it worthwhile. If you grow hostas, the sweetgum balls make a great mulch to keep slugs away, and if neighborhood cats use your garden as a litter box, sweetgum mulch keeps them away. I am still surprised that some enterprising gardener hasn’t bagged the stuff and sold it for either or both uses. Maybe you have a new cottage industry in your yard.

August 2012

QuestionWe live in north Boone County and have experienced two hot dry summers. We have a Japanese Cherry tree which is about 18 years old. This spring we had to remove a large dead limb from the tree which we assumed was caused by last year's hot weather. Now there is another large limb dying. When this limb is removed it will leave the tree badly misshapen. Should we remove this limb and try to prune the tree back in to a better shape or would this add to the stress. We have been trying to make sure it gets enough water but we only have a yard sprinkler and don't really know how long or how often to water. Would appreciate any advice you can give us.


AnswerJapanese cherry trees are one of the prettiest trees when in bloom, but unfortunately in our climate, they aren’t one of the longest lived trees—and that is even in years when we don’t have the type of summer we have had this year and last. They do need ample water, but remember the way to water a tree is to let it run low and slow for a long period of time over the entire area—a tree typically has feeder roots out as far as the tree is tall. Many folks are putting the hose out at the base of the tree, and while this adds water to the soil, it is questionable how much help this is giving the tree, since again, the feeder roots aren’t at the base of the tree. By now, the tree is in the process of setting flowers for next spring. I would enjoy whatever blooms it has to share next spring, and then do the shaping and corrections in the spring after bloom.

August 2012

QuestionWe will be expanding our front porch this fall, which will necessitate removal of a single low hanging branch from a nearby oak tree. Given the heat and drought of this summer, when is the best time to have it removed? The tree has been watered all summer and does not show any signs of distress.


Answerf you are just removing some lower limbs from established trees, there shouldn't be any issues. For small, young trees, we want extra foliage to help keep them established, but I think it will be fine to prune them as needed.

September 2011

QuestionYear before last I had a beautiful bed of hosta. It was in the shade of a large persimmon tree. We had a storm and had to cut the persimmon tree down, that left the hosta bed in the sun. The hosta bed is on the south side of my house. I have planted a mimosa tree in place of the persimmon tree. The mimosa is doing well, except for one problem. It has one very tall branch and one short one close to the bottom of the tree. Do I need to cut the top out of the Mimosa or will it finally branch on its own?


AnswerYou are probably going to have to provide some assistance. Prune it to a strong bud and it should branch out. Do so in late February to early April to catch the resurgence of new growth next spring. I know that many folks like mimosas, but they are not my favorite tree. They tend to be fairly weak and are susceptible to a wilt disease which causes an early death. Probably more information than you wanted since it is already planted in your yard. Watch your trees growth each year and gradually train it into the shape and size you desire. Wherever you prune, you should encourage branching. It may take a few years to get the desired shape.

April 2012

QuestionI have a Harry Lauder Walking Stick Tree that is approx. 15 years old. It started putting up suckers and I have continued to remove them. The suckers keep returning, more each year and larger. I am thinking about cutting it down at this point unless there is a solution to eliminate the problem since it is getting more difficult to cut off the suckers. Any suggestions would be greatly appreciated.


AnswerMost Harry Lauder Walking Sticks or contorted filberts are grafted onto a common filbert rootstock, so suckering is a common complaint. Other than pruning, there isn’t much you can do about them. I love the look of the twisted, gnarled branches, so I would continue to prune out suckers. If you really can’t take it, they do now sell Harry Lauder Walking Sticks that are not grafted, but grown on their own root stocks, and they will not sucker.

March 2012

QuestionI have an Acer palmatum, Japanese maple that is about 6 years old. It has never a problem and always beautiful. My problem is that although we thought we planted it far enough from the house, obviously we did not. Its huge umbrella is a perfect dome but the back side is against the house and it is rubbing against the house. I cannot or don’t want to move it. Can I trim off the back side and still have my beautiful tree? If so, when can I do it successfully and safely? It would be pointless to try and maintain it's gracefulness but a good 6 inches needs to keep it from rubbing against the house.


AnswerKnowing the eventual spread of a plant can help when determining plant spacing. Many folks plant their foundation plants too close to the house and have the same lopsided growth problems. You can prune it, but do so carefully. I would try to be very selective in your pruning so that it doesn’t have a sheared look at the back. Try to get in there soon before the foliage is fully on it, so you can see what you are doing. It is always best to err on the side of taking off too little, versus taking off too much. This will be a continuous problem, but you still want to retain as much of its graceful shape as possible. Don’t be alarmed if you see bleeding sap come from your cut edges—maples are prone to that in the spring as the sap is rising. It won’t hurt the plant.

October 2011

QuestionI have 72 Bradford Pear lining my driveway, planted in 1995, have never been trimmed except underneath so you could mow. I have had a little wind damage but so far it has been to the inside and you couldn't tell it. But with winter close, they will never withstand any ice and probably not much more wind. I have a tree service to give me an estimate but this time of year won't be like trimming in the spring. Will they survive the winter cut this late in the year?


AnswerYou are fortunate to have as little damage as you have had. I am also surprised by the sheer number you have. Pruning this late in the year shouldn’t hurt a pear tree. However, their two most showy seasons are fall foliage—which they have yet to have; and spring blooms, whose buds are set. If you want to wait until spring to prune, you can, but if you are worried about winter damage, then prune as the foliage sheds. The proper way to prune is to thin out excessive branching—don’t top the trees, nor limb them up like telephone poles. Both of those methods ruin the trees and make them more susceptible to damage. Good luck and if you do lose a few trees, consider replacing with a different tree. Diversity is a good thing in a landscape.

February 2012

QuestionI have a large Japanese maple in my back yard that is starting to take over the whole area. It is wide and low to the ground. My husband is afraid for me to prune it because he thinks I will kill it. When and how is the correct way to prune this type of tree?


AnswerI think the natural growth habit is quite graceful and effective in a landscape but if you need to be able to walk underneath it, you can selectively prune to do so. Don't try to shape it into a ball or box, but make selective cuts now to alleviate overall size. Try not to remove more than one third of the limbs, and do so at the branch collar or at a node--where there are buds that can start to grow and fill back in. I will say that Japanese maples have not had the easiest go of it during our miserably hot, dry summers, or the cold up in the NW last winter.

January 2012

QuestionMy Bradford pear tree top branches are beginning to spread open and it is losing the shape it should be. Should I have it trimmed to help it? Any suggestions?


AnswerJust as in humans, with age comes a little spread in the ornamental pears. They tend to lose their perfect tear-drop shape. You can do some thinning of the branches, but do not limb it up excessively nor top it. Lightening the load can prevent some of the spread.

November 2011

QuestionWe planted an Autumn Blaze maple tree to honor of the birth of our first granddaughter in October 2007. It is planted in full sun and did thrive for the first two years. Then, it simply died the third year. However, during the fourth year, about five or six suckers came up around the original tree. When should I choose the best of the suckers and cut back the others? One of these must make it, my granddaughter, now 4 years old, knows that this is "her" tree. It is so important to us that this little tree continue to thrive in spite of the death of the main tree.


AnswerIn the spring, when the tree begins to leaf out and you can assess the healthiness of the sprouts, then choose the strongest, straightest one, and prune all the others out. Make sure you keep it watered and mulched. If the tree was grafted, this could be a root sucker from beneath the graft union, but it will still be a red maple, it just may not be the named cultivar. Over the next few years, you may need to do some pruning to train it back into tree form.

December 2011

QuestionI have a 25 year old dogwood tree that is blooming now. I noticed a couple full sized blooms last Saturday. Sunday I noticed one additional branch full of smaller blooms. How unusual is this? The dry hot summer has stressed the tree, which has about half its leaves withered and brown. I had never pruned the tree, until July of this year, when I remove quite a few of the lower limbs to allow sunlight to shrubs and various plants under the dogwood. I painted the wounds where I cut off the branches.


AnswerYou are not alone--many spring bloomers have had some errant blooms this fall. My loropetalum shrub is in full bloom right now! Many of our plants set their flower buds early and shut down early to deal with our horrendous summer. Then we finally got some rain, it turned cool, heated up again and they thought spring had arrived. There is nothing you can do but enjoy the blooms. Assess the damage next spring to your tree from the summer heat and prune as needed after they finish blooming next spring. Tree paints for pruning cuts are not needed--a nice clean cut is all you want.

October 2010

QuestionMy neighbor recently ran into my Bradford Pear with his truck, knocking off a large section of bark. What can I do to treat the damaged area in hopes of saving the tree? Picture attached.


AnswerOnce a tree is wounded, the wound will always be there, but you can help by cleaning up the wound. Cut off any lose or jagged bark and try to keep it as clean as possible. Time will tell how deep the wound went and how much, if any damage will occur to the top. Have you seen any signs of stress to the top of the tree that is on the side where the damage is? Wound dressings or tree paints are ineffective, the best remedy is a clean wound.

September 2010

QuestionI have a large silver maple tree in my back yard. The trunk is about 30 feet from my house. I am sure it is quite old, about 5 feet in circumference. I am concerned about the large roots that are reaching the patio at my house. The roots have come to the surface and over the years have been shaved off by the lawn mower. It is also dropping a lot of dead limbs, not the large ones, but smaller limbs. Do I need to have this tree taken down or would pruning it severely lessen the danger of damaging my foundation?


AnswerSilver maple trees grow rapidly and surface roots are often a problem. Because of the rapid growth, they often start to fall apart with age, dropping limbs and splitting. Thirty feet away from the foundation should be ample. We recommend that trees be no closer than 15-20 feet from a house, and I like even further for large trees. I don't think you are in danger of damaging the foundation of your house, but the patio may be another story if it is closer to the tree. I am sure it is giving you much needed shade, so the thought of removing it is not a happy one. You have two options. One is to consider planting another tree nearby but with enough space to get growing. Once it gets established, you may want to remove the maple. Or you can thin the existing tree and remove the deadwood and excessive branching.

September 2009

QuestionMy red Japanese maple has grown to almost five feet tall, and I would like to prune it back to about three feet and then keep it that height, allowing it to branch it. Would I ruin it to prune it at this time of year?


AnswerPruning a tree now is not going to hurt the tree, but I think you need to assess what the tree will look like. First of all, the natural shape with a bit of corrective pruning is preferable for a Japanese maple. If your tree is not a true dwarf, pruning it annually to keep it at the three foot height is going to ruin its shape and turn it into a “meatball”. You might consider planting a different species that stays short, and requires less pruning. Some choices include: Acer palmatum: ‘Beni Himo’—mature height 1-2 feet; ‘Chishio’—mature height 3-4 feet; or 'Goshiki Kotohime'—mature height 2-4 feet and 'Shishi Yatsubusa' which grows 3-5 feet in 10 years.

June 2010

QuestionI have what I thought was a Japanese maple tree, but decided I don't know the difference between a Japanese maple and a Chinese maple. Mine is green all summer then red in the fall. My neighbor’s tree is red all summer. They are both cut leaf types. Also do you have any advice on pruning?


AnswerI think you both have a Japanese maple. While there is a Chinese maple (Acer discolor) it is fairly rare and the leaves are not cut leaf. As to the difference in color, there is a difference in variety. The term Japanese maple includes a whole host of different species and then different cultivars within the species. Acer palmatum is the most common tree called Japanese maple. A. p. dissectum is the cut leaf form. Many of the Japanese maples that are red in the spring turn green throughout the summer then have great fall color. A few have been bred to hold their red color all season, while others are variegated or have yellowish tinges. The red forms include ‘Bloodgood’--(but if it gets too much sun it too can turn a bit green) with a standard leaf. ‘Crimson Queen’ and 'Ever Red' are cut leaf types which should hold the red color. Regardless of the color during the growing season, they are beautiful trees and all have outstanding fall color. As to pruning, it all depends on the type of tree you are growing and its mature size. Some get no taller than three feet and cascade, while others can get 20 feet or more in height. Selective pruning to maintain size or to open them up can be done, but don't try to shape them into a ball or box. Pruning can be done now if it is light pruning.

January 2010

QuestionI have a beautiful, very large Bradford Pear in my front yard -- about 7 or 8 feet from my house. I'm guessing it is 14 years old since the house was built in 1996. The roots have apparently developed superpowers! They've caused a shift in the sidewalk between the tree and the house and pushed over a brick flowerbed border! There was no evidence of this a year ago -- but now it's significant enough that it could cause someone to fall. Do I need to dig down and find the roots causing the problem and chop them off? Would that kill the tree? Should I chop it down? It is my only tree.


AnswerOrnamental pear trees tend to have an abundance of surface roots which can make walking, mowing, etc. difficult under the tree. The roots have a finite amount of space in which to grow when planted in a home landscape and if there is a sidewalk or flower bed in their path they fill it, sometimes causing the sidewalks to crack or the flower beds to move. If you cut the offending roots, it may cause serious damage to the tree. You don’t know what portion of the tree the offending roots are supporting. Even if there is limited damage, more roots will grow back. I think you are lucky it hasn't happened earlier, since Bradford pears are LARGE trees at maturity and should not be planted any closer to your house than 15 - 20 feet. At 7-8 feet away, I would suspect that the canopy is somewhat lopsided, since the branches can't extend any wider than the house on one side. It is your call about removal. The tree is going to get larger, and the larger the top the larger the root system. You may want to plant a new, different species of tree away from this one, allow it a year or two to get established and then take out the Bradford pear.

March 2010

QuestionI am unable to determine if one of two trees in my front lawn is dead. Both, according to my neighbor, are white oak. One shed all of its leaves in the fall and is now appearing to form sprouts. The other did not shed leaves; they turned brown but still remain. Some of the leaves did fall with the strong winds and rains of the winter. It is difficult for me to determine if there is any sprouting. How long do I wait to see any greenery? With the advancement of springtime, I am anxious to begin working in the lawn, but am fearful that anything done might be upset if the tree has to be removed. I do want to save the tree if possible. I did call my local Cooperative Extension Service, but was advised to wait until spring, that there was no danger of the tree falling. It is very near to the house.


AnswerThe tree that did not shed its leaves is a concern, but you still need to be patient and wait to see if they leaf out this spring or not. We are having a late spring this year, so I wouldn’t make any decisions until mid to late April. Rarely does a tree die and decay enough to fall over in one season. See what happens this spring and then prune out any dead branches or trees. Any idea on what caused the problems? Any recent construction, grade changes, etc?

December 2008

QuestionWe purchased an October Glory maple tree about three years ago and it is now about 10 to 12 feet tall. On your radio show, I heard you say that lower branches will always stay low and not grow upwards with the height of the tree. Is it time to trim the limbs to about six or seven feet off of the ground?


AnswerThere has been some debate recently about how long to leave the lower limbs attached, as they help the tree manufacture food and aid in root establishment. If possible, leaving the lower limbs attached for two to three years is advisable. However, if the tree is in the yard and you need to walk under it, then by all means go ahead and remove the lower limbs at the branch collar. Since your tree has been in the ground for three years, I don't see any issues with removing the lower limbs now. Limbs will never grow higher than where they are currently attached, since new limbs grow from the top of the tree—the tree does not continue to raise up out of the ground. No pruning paints or wound dressings are needed after pruning, just make sure you have a nice clean cut and the tree should be fine.

October 2007

QuestionMy neighbors Dogwood tree has almost died. Mine has a number of dead limbs. Should I cut them out? If so should they be painted with pruning paint?


AnswerIf you are sure the limbs are dead and haven't just defoliated early, then go ahead and prune out the dead wood. You should not use a pruning paint or wound dressing--the key is a nice clean cut. Prune them out at the branch collar--not flush with the trunk of the tree, but not leaving a stub either. Dogwood trees don't handle stress well. Whether it is wounding from a lawnmower or weed-eater, drought stress, storm damage or ice damage, once they begin to decline, it can be difficult to reverse the trend. Take a close look at the tree next spring when the tree leafs out. Make sure you keep the tree watered, as dogwoods are very shallow rooted. If you are fertilizing your lawn area, you are also getting fertilizer to the tree.

June 2006

QuestionMy husband and I are having a disagreement - A cypress tree is planted close to a gate and branches have grown so much they are blocking the entrance. He says cut the branch off. I say tie it back, because as it grows the branches will grow up and out of the way and I don't want to ruin the shape. He says the tree grows from the top and the bottom branches will always be where they are right now?? What is the correct thinking on tree growth and pruning?


AnswerAs much as I hate to tell you - your husband is right. Any branches that are down low will always be there. New growth is from the top up. I think many people get the misconception of trees pushing out of the ground and moving up from all the cartoons--consider Jack and the bean stalk--he got on and it took him to the giant. Pruning off a few lower limbs is not going to hurt anything, and the tree should grow taller. Making sure you can see to pull out of your drive is also safer.

May 2006

QuestionOur Bradford pear trees bloomed beautifully and greened up this spring. Now there are numerous dark brown leaves on the trees. They are in clusters all over the tree. It does not appear to have insects or anything else causing the problem that is visible to the naked eye. What can I do to save the tree?


AnswerThis has been a fire blight year. We are seeing many fruiting and ornamental pear trees with black leaves on the tips of the branches. Fire blight is a bacterial disease that is spread during flowering. Once the weather heats up and stays in the 80's it usually stops spreading. That doesn’t mean the disease goes away, it just stays put. At this point there is no spray schedule. For now simply cut out the damaged branches--6-8 inches beneath visible damage. Sterilize your pruning shears with either alcohol or a bleach solution in between cuts. This prevents you from transmitting the bacteria from one cut to another should you cut into damaged tissue. Be sure to clean and oil your pruners before storing them.

April 2006

QuestionI have a huge dogwood tree in my front yard. The umbrella of the branches measures about 30 feet in diameter. And it has been gorgeous this year. I am and have been concerned about exposed roots under the tree. Basically, nothing grows under the tree, except unwanted weeds. My questions are: Can I sod over the roots? Should I cover the roots with top soil and sod over all of it? Or, should I just leave things as they are? I really would like to have some sod under part of that umbrella, probably not all the way to the trunk. What kind of watering should the tree get in summer and early fall when there is little or no rain? Also, when is the best time to trim dogwoods?


AnswerDogwood trees are shallow rooted trees and really don't like a lot of competition from other plants -- even grass. I would not cover up the roots with soil or sod. Your best bet would be to mulch the area. This helps to conserve moisture, covers up the roots, and should reduce the weed issue -- and prevents any damage from a lawnmower or weed eater. If you want to create some pockets of soil for a few perennial plants, that would be fine, but don't bring in a load of soil or you will smother the roots and damage your tree. Water regularly throughout the summer for best flower production. If they need trimming, now would be the time to do it -- immediately after bloom. Don't try to prune them into formal shapes, or do any topping, but if you need to remove low limbs or do some corrective pruning, get it done soon. Dogwoods set their flower buds in late summer through early fall.

January 2013

QuestionI have a Bradford Pear tree that continually sends up dozens of saplings from its roots. Why is the tree doing this and how can I discourage it from continuing?


AnswerSome trees tend to be prone to suckering more than others. Unfortunately, there isn't much you can do to stop it. Remove any sprouts this spring, then pay attention late in the season. If any new sprouts have emerged then, summer pruning tends to be more dwarfing or has less potential to re-sprout than early spring pruning. Cut the saplings slightly beneath the soil line, mulch and hope for the best.

March 2006

QuestionI have two Japanese maple trees that need some pruning (limbs too low to the ground, and several too wide) for shaping/appearance purposes. Can I do it now or do I need to worry about sap running? For some reason they never dropped their leaves last fall, but they are shriveled and brown. I've noticed the same is true on others' trees in the area. Any idea why it happened?


AnswerYou may prune them now. The bleeding that occurs in the spring will not hurt the plant, but if it bothers you, you can wait a few extra weeks. Many of our trees didn't drop their fall foliage this year, especially Japanese maples. The extremely dry weather during the first frost had something to do with it. Somehow the mechanism that drops the leaves (the abscission layer) shut down early and the leaves stayed attached. Normally as the days get shorter, the cells in the abscission layer become more dry and corky. The abscission layer is found where the leaf is attached to the stems. This corky layer of cells slowly begins to block transport of materials such as carbohydrates from the leaf to the branch as fall sets in. It also blocks the flow of minerals from the roots into the leaves. Normally this connection between cells becomes weakened, and the leaves break off with time. Somehow this didn't fully occur this year. As the new foliage emerges this spring, it should push the old leaves off.


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