Pine sawyers (longhorn borers with long antennae) feed on the twigs of healthy trees from May to July. In this way, the sawyers introduce the pinewood nematode into the tree. Nematodes are tiny wormlike creatures barely 1/100th of an inch long. Nematodes multiply rapidly in the tree. As a result of nematode feeding, the tree’s water moving system becomes clogged and resin flow slows and then stops. Wilt symptoms develop and the tree dies.
Early symptoms of Pine wilt may include reduced shoot growth, needle length and bud development. Pines turn off-color (dull green) in August through October. Symptoms first appear on one or a few branches but often develop quickly throughout the crown. The tree may turn from green to brown seemingly overnight. Trees die quickly in one or two months.
The straw-colored needles will stay on the tree. Tree branches become dry and brittle.
Pine wilt-diseased trees cannot be saved and must be removed by May to prevent the spread of pine sawyers and nematodes. The entire tree, including the stump, should be removed. The wood must be chipped or buried. Do not keep Scotch or Austrian pine wood for firewood.
Healthy pine trees should be protected. The control method is a nematicide injected directly into the tree trunk. Early to mid-spring is the best time for this tree service. Trees must be trunk -injected once every other year for protection.
A Trees "R" Us, Inc. certified arborist can provide a free quote customized for your landscape local to the Chicagoland area.
Additional preventive measures property owners should consider include:
Dormant Pruning. Trees with leaves or dead, dying or weak branches pose risk to people and property.
The lack of moisture the Chicago are has experienced this year is impacting our trees in ways we won’t see for a year or two. Regular watering, even after sprinkler systems have been winterized, supplemented tree and shrub root watering is the best way to keep your trees and shrubs strong and healthy.