Xtremehorticulture

Apricot Tree Dying in Mid Summer

Q. My apricot tree is 15 years old. I have emitters around most of the canopy. I gave it fruit tree fertilizer in early spring. This spring it developed a lot of apricots then a few weeks later the leaves started turning brown and falling off. I fear my tree is dying. Any suggestions? A. This is the time of year we see borers finish their nasty work. This is not peach tree, or crown borer that gets into the soil as it does further north. These borers have been tunneling just under the bark, staying in the tree, and are “flatheaded borers”. It is possible that borers may have been a problem before your tree was 15 years old. When we see the tree dying it is often times later in the year (usually July or August) when it gets hot. Often times the tree has an exposed trunk facing west or south. The trunk gets hot, scorches or sunburns and the borers infest the tree where there is damage. Like I said, this borer infestation can happen over several years when it is older like yours. In young trees it can happen over one or two years. What to do? Look for borer damage of the tree trunk where it is exposed to direct sunlight. I would get borer control insecticide containing the active ingredient imidacloprid and treat it now. Make sure a soil drench is mentioned on the label. You can always look for borer damage after you apply the soil drench treatment. Normally this treatment is done earlier in the year before damage is obvious, around March. But it is worth the treatment now in hopes the tree will improve. Since the fruit has already been harvested (it finished flowering in February) the soil drench is straightforward. The tree may continue to get worse before it gets better, or the tree may die outright because the visual damage is so extensive. Your other option is to remove the tree and buy an apricot and plant it in the same hole. I would recommend any apricot on any dwarfing rootstock. Plant any of them in October when it is cooler. If it is borers, they are only in the tree and not the soil.

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Q. What should I be doing now to control borers in my African sumac? A. Make sure there are borers present and has been correctly identified and not just guessed at. I have not seen damage to it from landscape borers. That doesn’t mean it doesn’t happen but I just have not seen it. Imidacloprid can be used protectively or if the “landscape borer” problem is present. If the borer has caused extensive damage to the tree, you may have to “weigh” whether it is worth applying it or not. Sometimes replacing the tree is the more profitable solution. Unlike peach tree borers, this “boring insect” is in the tree, not the soil. Use insecticides or pesticides that contain imidacloprid as an active ingredient. To find if imidacloprid is in the package, find the active ingredients listed on the front or back. The imidacloprid liquid mix can be used as a soil drench only if it says it can be used as a soil drench on the label. For me, soil drenches are the most effective way to apply it because plant roots were designed for the uptake of liquids. Other methods of application exist. To avoid any references to CCD (Colony Collapse Disorder) and honeybees, make applications after the tree has finished flowering to minimize any CCD to pollinators. Since African sumac was made available from south Africa, the flowering of this tree is during the winter. The time to apply a root drench is any time after growth begins in the spring and the tree finishes flowering.

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