Q: I have a problem with my Malus Prairie Fire crabapple tree. It has many suckers coming up. Could you tell me what causes this? I would like to know how to cut and prevent them from returning. It is planted on a mound. Because Lincoln is known for its clay soil, I added plenty of mulch and compost at the time of planting, about eight years ago. The suckers have just come up in the last year and as you can see, are quite large. Would I also be able to save them and plant them somewhere else in my yard?
Fran Swart, Lincoln
A: According to UC master gardener June Bleile, crabapples are prone to developing suckers from the apple root stock. These suckers drain energy and other resources from the parent plant.
To help control this problem, pay attention to soil moisture and irrigation. Use a trowel to take a look at the soil around your tree. When soil within the drip line (the outer edge of the tree’s foliage) is dry down to 4 inches, water slowly, deep watering to a depth of at least 12 inches.
Place a 4-inch deep layer of organic mulch, such as bark, around the base of the tree, keeping the material at least 3 inches from the trunk. Cut to ground level any shoots that grow from the tree roots. Remove these as soon as they form.
You cannot use herbicides such as Roundup to control root suckers as the suckers are connected to the main plant and the chemical will move from the root suckers to the main tree, possibly causing damage or death. Roots should be pruned off at the soil level whenever they appear. Although it is frustrating to have to do this time after time, it is the only safe way to remove the suckers. Persistence will eventually pay off.
As for replanting the suckers, if you are able to cut the sucker away from the root without damaging the tree root, you might be able to transplant it to another place in your yard. However, if your crabapple has a grafted root system (and most do), the sucker tree will not be the same as your present Malus Prairie Fire crabapple tree.
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