We turned to the experts for help with this one, Roderineo, especially because you have them in your trees. Because the fleas seem to overwinter in the leaf and plant residue at the base of the trees (see the following), you might consider cleaning up those areas.
• Here’s a forest management site that describes their life cycle: https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5186816.pdf
• Here’s the Oregon Cooperative Extension: http://oregonstate.edu/dept/nurspest/alder%20flea%20beetle.htm
• Britain’s Royal Horticultural Society has very good information; here’s what they say about this: https://www.rhs.org.uk/advice/profile?PID=850
We turned to the experts for help with this one, Roderineo, especially because you have them in your trees. Because the fleas seem to overwinter in the leaf and plant residue at the base of the trees (see the following), you might consider cleaning up those areas.
• Here’s a forest management site that describes their life cycle: https://www.fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5186816.pdf
• Here’s the Oregon Cooperative Extension: http://oregonstate.edu/dept/nurspest/alder%20flea%20beetle.htm
• Britain’s Royal Horticultural Society has very good information; here’s what they say about this: https://www.rhs.org.uk/advice/profile?PID=850
We hope this helps!