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
- Do you have tips on planting trees and shrubs?
- How can I make my lawnmower safe?
- I notice groups of about 4 or 5 pine needles buried into the flower beds and am wondering what type of bug is pulling them into the ground in the fall. They do not get ther naturally because of the way they are sticking out of the ground. Half buried. I am just wondering what creature this might be and do I need to do something about it?
- How do I prevent aspen sprouts from coming up in my lawn?
- What is killing my lawn? It was fine in the spring, and now this summer, it is looking dead in patchy spots.
- I have 30 acres of dry farm high on the west side of cache valley and would like like to cover it with many trees that are likely to survive and will eventually provide shade. What should I plant?
- I have a lawn full of spiders. When I go to the flowers beds, probably a 100 spiders run out of the grass and bed. The spiders are about 3/8 of an inch long and dark brown. I would just like to get rid of them. What is the best approach?
- What is killing all the scrub oak and where can I find information on how to save the scrub oak I have that has not been affected by it yet?