By: Teo Spengler
If a backyard tree dies, the mourning gardener knows he or she must remove it. But what about when the tree is dead on one side only? If your tree has leaves on one side, you’ll first want to figure out what is going on with it.
While a half dead tree might be suffering from a variety of conditions, the odds are that the tree has one of several serious root issues. Read on for more information.
Insect pests can cause serious damage to trees, but they rarely limit their attack to one side of a tree. Similarly, foliage diseases tend to damage or destroy the entire canopy of a tree rather than only half of it. When you see that a tree has leaves on one side only, it is not likely to be an insect pest or leaf disease. The exception might be a tree near a border wall or fence where its canopy can be eaten on one side by deer or livestock.
When you see that a tree is dead on one side, with limbs and leaves dying, it may be time to call in a specialist. You are likely looking at a root problem. This can be caused by a “girdling root,” a root that is wrapped very tightly around the trunk below the soil line.
A girdling root cuts off the flow of water and nutrients from the roots to the branches. If this happens on one side of the tree, one half of the tree dies back, and the tree looks half dead. An arborist can remove some of the soil around the tree’s roots to see if this is your problem. If so, it may be possible to cut the root during the dormant season.
There are several types of fungi that can cause one side of a tree to look dead. The most prevalent are phytophthora root rot and verticillium wilt. These are pathogens that live in the soil and affect the movement of water and nutrients.
These fungi can cause a decline or even to the death of the tree. Phytophthora root rot appears largely in poorly drained soils and causes dark, water-soaked spots or cankers on the trunk. Verticillium wilt usually affects branches on only one side of the tree, causing yellowing leaves and dead branches.
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A: I appreciate you bringing me clippings of the tree. It was especially important to bring in limbs with living leaves still attached. It is often difficult to determine the cause of a problem if the only material I see is totally dead. I was unable to locate any disease or insect damage so the next thing to do is look at the root area. In several recent instances I have found the same damage you described and discovered girdling roots at the base of the tree. A girdling root is similar to having a tourniquet wrapped around your arm. What will eventually happen to your hand if the tourniquet is left in place for a long period of time? Your hand would have the blood supply cut off and the limb would be lost. The same thing can happen to a tree branch if a girdling root is allowed to grow around another tree root.
We recently planted fourteen new trees at the James S. Pages Governmental Complex and every one of these new trees had some degree of girdling and circling roots – from mild to severe. It is important to examine the root ball of any tree or shrub you plant. Remove those girdling or circling roots before you plant. Remove the top layer of soil and root mass so you can examine the root structure carefully. In your situation, the plant has been in the ground for several years but it is still important to remove any roots growing into another root. Cut the girdling root just above where it starts to grow over the other root. You may need to use loppers to make a clean cut. Do not add any amendments to the soil – no black cow or fertilizer. Just be sure the plant is well irrigated for a few weeks to help get it through the shock of losing a major source of water. Keep lawn grass as far away from the roots as possible. Be sure the mulch is not too deep – only about 2-3 inches. Never allow mulch to be piled up around the trunk tissue, which can provide the perfect environment for disease. Allow 18 – 24 inches area around the trunk of the tree or shrub which should contain nothing but soil and air.
The damage you see in the above photo is called Vertcillium Wilt. Verticillium wilt attacks all kinds of plants, usually with devastating results. I’ve had it attack at least three if not four of my pretty mature Japanese maples.
Verticillium Wilt is a soil borne, fungal type of disease that affects the plants ability to move water to certain parts of a plant, causing that section of the plant to fail, the die. There is no chemical control, prevention or cure. It’s just something that happens, but . . . but . . . but . . . it is not the end of your tree!
Obvious Verticillium Wilt on Crimson Queen Japanese maple.
I’ve had this happen to at least four Lace leaf weeping Japanese maples in my landscape and it’s happened over a period of time. I’ve read all kinds of explanations of what exactly is going on in the soil to cause this, but quite honestly, in all four cases my soil conditions were different, never soggy, just different soils. Didn’t matter, it still occurred.
You can take my opinion for what it’s worth and my only qualifications to offer such an opinion is to say that I’ve not studied a great deal about plants but I’ve spent the better part of my life, starting at the age of sixteen, I’m 63 today, crawling around in the dirt, working with plants on a daily basis. You can not stare at that much dirt and that many plants and learn valuable things through shear observation. Often times, those observations are more accurate that what you find written in text books.
Believe it or not, this tree will survive and it will recover nicely. And if you remind me I’ll add updated photos to prove it.
There is nothing you can do to prevent it and there really is no cure for it except to prune it out of your plant.
There are certain ground rules for planting and caring for Japanese maples and I’ll cover those here. If you follow these recommendations I think you can be assured that you have done everything you can to give your Japanese maples a good home. But Verticillium Wilt can still occur and it is certainly going to be heart breaking, but in most cases the trees can and will recover nicely.
If your Japanese maple suddenly has a large branch, or a pretty big section of the tree that appears to suddenly just up and die. More than likely it’s Verticillium Wilt. It usually starts with some discolored leaves, then the leaves turn brown and crispy and often will not drop from the tree right away. They just curl up and turn brown and crispy and often stay on the branch. Once your tree gets to this point it’s probably too late to save that particular section of the tree or that branch. Before you remove any branches do a scratch test to make sure that they are dead.
This is how you test to see if a plant, or a branch on a plant has died. Just scratch the bark of your plants with your finger nail. If the tissue below the bark is green and firm your plants are fine. If the tissue is brown and mushy that part of the plant is dead. Once that tissue below the bark becomes brown and mushy there is no saving that part of your plant.
As I mentioned earlier in this article, I’ve experienced Verticillium Wilt on several of the Japanese maples in my landscape and in each case I was able to prune away the dead part of the plant and eventually have the trees make a really nice recovery. After pruning you are obviously left with a big gaping hole in your plant, but you’d be surprised at how fast it will completely fill in. I’m not talking days, weeks or months. It is going to take at least two or three years to fill in nicely. But it’s always worth the wait to save a beautiful Japanese maple.
Japanese maples have really hard wood so you will need really sharp shears of maybe even a pruning saw to remove the dead branches.
Before you start pruning clean up the blades of your pruning tools with alcohol wipes or something else suitable. Then clean the blades after each cut.
Do I do that? No. I’m a maniac! I’ve never done that. But I recommend that you do as I say, not as I do. I take chances.
Questions, comments or mean things to say? Post them below and I will respond.
Pruning can actually be done at any time of the year however, recommended times vary with different plants. Contrary to popular belief, pruning at the wrong time of the year does not kill plants, but continual improper pruning results in damaged or weakened plants. Do not prune at the convenience of the pruner, but rather when it results in the least damage to the plant. There is little chance of damaging the plant if this rule is followed. In general, the best time to prune most plants is during late winter or early spring before growth begins. There are exceptions to this rule, and they will be noted under the discussion of the specific plant groups. The least desirable time is immediately after new growth develops in the spring. A great amount of food stored in roots and stems is used in developing new growth. This food should be replaced by new foliage before it is removed if not, considerable dwarfing of the plant may occur. This is a common problem encountered in pruning.
It also is advisable to limit the amount of pruning done late in summer as new growth may be encouraged on some plants. This growth may not have sufficient time to harden off before cold weather arrives resulting in cold damage or winter kill. Prune plants damaged by storms or vandalism or ones with dead limbs as soon as possible to avoid additional insect and disease problems that may develop.
From disease to winter weather blues, trees sometimes have setbacks before they wake up in spring.
Maple trees are particularly troubled by unseasonably warm days followed by a sudden frost.
Your tree may have jumpstarted growth during a warm stretch in winter, expecting temperatures to stay mild. Then, it lost its progress when the weather turned cool again. There’s a chance your maple will still leaf out, but it might be slow to grow the second time around.
For ornamental trees like plum or cherry, the problem could be fluctuating weather or just fatigue. Like maples, ornamental trees can get tricked into sprouting too early. If that’s the case, they’ll show signs of frost damage and may not bloom again this year. But these trees might also skip out on spring growth simply because they put out a particularly heavy amount of growth last year. In this case, you should expect to see new blooms next spring.
Elms and oaks sprout leaves later after the cold weather is gone’. Because of this, it’s not uncommon for these trees to wait until late spring or even early summer to grow leaves.
If your tree looks healthy (which you’ll find out how to determine below), just give it a little time!
Spring and tree disease go hand in hand, and anthracnose is a disease that can hinder leaf growth on trees like ash, maple, oak or sycamore.
Trees affected by anthracnose might prematurely lose their first flush of leaves early on. If there are any leaves left, they’ll be wilted, curled and brown. After the infection has subsided and if the tree is otherwise healthy, a second flush of leaves should occur.
You’re in luck! Often, a tree problem like this has an easy solution.
Here are a few ways you can help your late bloomer:
Mulch trees to help them recoup from winter.The proper amount of mulch keeps trees moisturized as they gain enough strength to grow more leaves.
Water. Water. Water.Proper watering helps trees that may be under stress from pests or disease.