Pine Wilt
Overview of pine wilt
Pine wilt causes rapid wilting and dying of pine trees, particularly Scots (Scotch) pines. Pine wilt is particularly common in scotch pines but is capable of infecting other non-native pines as well.
Signs and symptoms of of pine wilt
Symptoms of the disease include wilting, browning needles and eventually tree death.
Disease cycle of pine wilt
The pine wood nematode is spread by pine sawyer beetles, which bore under the trees bark. Nematodes and their eggs that have attached to the beetles are then transported to other trees that the beetles colonize.
Type of Sample Needed for Diagnosis and Confirmation
To test for Pine wilt the diagnostic lab requires a branch 2-3 branch samples that are at least 2 inches in diameter.
The Iowa State University Plant & Insect Diagnostic Clinic can help you to investigate and confirm if you plant has this disease. Please see our website for current forms, fees, and instructions on collecting and packing samples. Contact information for each states diagnostic laboratory for U.S. residents. If your sample is from outside of Iowa please do not submit it to the Plant & Insect Diagnostic Clinic without contacting us
Management of pine wilt
Keeping other trees stress free and avoiding wounding can help to reduce this spread, as the beetles are attracted to such trees.
Inspecting your other nearby pines is critical to controlling this disease. Dead and dying trees can be sources of bark beetles. Removal and destruction of these trees is the only effective line of defense in controlling pine wilt. The optimal time to remove such trees is during the winter months when the beetle is inactive. Infected trees should then be promptly burned, chipped or buried to reduce the risk of bark beetles spreading to healthy trees.
Unfortunately, chemical treatments have proven ineffective and impractical for pine wood nematode. For this reason, prompt action needs to be taken with infected trees to reduce spread
Pine wilt causes rapid wilting and dying of pine trees, particularly Scots (Scotch) pines.
See this link for more information about pine wilt.
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