Is there anything that can be done after bronze birch borers attack? White paper birch are 2 yrs. old with proper planting and watering. Older established trees of same species on the property are fine. Trees are defoliated, classic 'D' shaped exit holes, classic rapid woundwood formation under the bark. Should they be pulled and replaced? Will the next trees be invaded too? Should I wait for next year and see? Can an OTC pesticide work? Does spraying anything work at this stage?
<peter>
Posted
I never heard of that insect feeding in a 2 year old tree. Please check your facts and report back.
<Sue>
Posted
Sorry, by two years old I meant that they were planted two years ago. The trees are 2-2.5" in diameter at 6" above ground. They were B&B from a nursery with a good reputation so I don't think they had borers or any larval stage when purchased. Thanks
<Mark>
Posted
Below is a link to a site about managing this pest. I find it interesting that you say other established trees are fine. Combined with the statement at the linked site saying the pest tends to attack poorly-sited trees, I wonder if that shouldn't be a big consideration for you.
Also, I would guess the trees are probably doomed if they are defoliated. The typical girdling associated with this kind of attack will not go away. However, I have no experience treating for this pest. I'm located in Northern California.
