Ask a Question
Notify Me On Question Update
Email this Question
Is There Any Way To Eliminate Borers That Leave What Looks Like Sawdust At The Base Of Our Aspen Trees?
Rate This FAQ
Your aspen trees have aspen borer, an insect in the long-horned or round-headed beetle group. This insect problem is very common. The injury is caused by the larvae feeding on the inner wood of the trunk. Their tunneling weakens the wood and allows the invasion of canker and decay fungi. Borer wounds typically “sap” or “bleed.”
Aspen is an attractive host for the insect, especially when the aspen tree is already under some kind of stress or decline. Common stresses for aspen trees in our area are iron deficiency (yellow leaves), poor watering regime (too much or too little), aspen leaf spot (fungus causing leaf spot - common following wet springs or when sprinklers water the leaves of trees), oystershell scale (insect that feeds on limbs and trunk of tree, sucking out sap), and aspen borer (beetle larvae that bore holes into trunks of trees). Aspen is not well adapted to living in the valley areas. They do much better in the mountains.
Suggestions to reduce aspen borer problems:
* Don’t plant aspen, select another tree species that is well suited to our valley growing areas and not as susceptible to insect injury.
* Grow aspen in a grove with continual renewal of trunks rather than as single specimen trees in your landscape. Aspens have a strong ability to sucker and send up new shoots. Remove aspen trunks when signs of borer injury are observed (sap running down trunk, accumulation of sawdust at base of hole or tree) and allow new trunks to fill in the open spaces - aspen are quick growers.
* Keep aspen trees as healthy as humanly possible - treat with a chelated iron product in the spring to reduce iron chlorosis, prevent sprinkler water from getting onto leaves (promotes aspen leaf spot disease), prune out dead and dying limbs, water properly (water as a tree, not your lawn - this means infrequent, deep waterings), remove trunks infected with borers as soon as they are observed. A healthy, vigorous tree will resist borer attack.
* You cannot remove the damage that the borers have already done. You can help (sometimes) reduce further damage to the injured trunk and others in the area by well-timed insecticide treatments to the trunks. This is costly, time consuming and involves some risks (pesticides should always be used properly - follow the label directions and wear appropriate protective clothing; there may also be environmental safety concerns).
* You must treat before the adult beetles lay their eggs in the late spring through summer. Once eggs hatch and larvae bore into the trunk, the damage is done. Chlorpyrifos (Dursban) insecticide products labeled for shade trees are the recommended treatment. Apply a spray that drenches the main trunk of the trees every 3-4 weeks from May-July in northern Utah.
Submit Your Suggestion
Other Questions In This Topic
- Could you pleae identify the pine-like tree on the north side of our home? The needles are on two sides of the twig rather than on all four sides. They (the needles) are very soft and are dark green. At this time of the year (Sep), the trees bear red berries. The trees are approximately 35 years old and are 12-14 feet tall. Thank you very much for your assistance!
- I live in rose park and am selecting trees to add to my backyard. I have full sun and dark rich soil. I want a good shade tree but am not sure what would be best. I have been looking at different types of maple trees but am wary about their growth rates. Are there any trees that you could recommend?
- I have a very large, beautiful Cottonwood tree on my property, that is near the property line with my neighbor. She wants to put in a new fence, because the tree has been pushing up the posts for her old fence. The fencing company has said that they can put in a new fence, but they will have to "shave off" a bit of the tree trunk and possibly some of the root near the surface of the ground. I am worried that something like that could lead to the tree getting sick or dying. I want to keep peace among neighbors, but it would be a disaster and very expensive to lose the tree because of something likethis. Can you please tell me if a Cottonwood tree is hardy enough to withstand such a "shaving" procedure?
- Why are the needles on my spruce tree turning brown and dropping?
- Last May I planted an eight foot Sub-Alpine Fir in my new yard. My soil is very sandy. We deep watered the tree once a week throughout the hot season. The tree never showed any sign of stress until now (March). The ends of the branches are turning brown. I know these trees are sensitive. What can I do to best ensure the tree survives?
- Why are my cherries wormy?
- How do I kill gophers in my lawn?
- How can I conserve water and still have a nice lawn?