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Slide Information . Pine Wilt Nematode Megan Kennelly Kansas State University. Pine Wilt. First found in Kansas in 1979 Pine wood nematode. Photo by Judy O’Mara. Image from Jon Appel, Kansas Dept of Agriculture. Pine wilt hosts. Common on Scots
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Slide Information • Pine Wilt Nematode • Megan Kennelly • Kansas State University
Pine Wilt First found in Kansas in 1979 Pine wood nematode Photo by Judy O’Mara
Pine wilt hosts • Common on Scots • Also starting to see it on Austrian pine, and Mugo • Drought stress • Beetles prefer to lay eggs where resin flow is reduced
Pine Wilt: Symptoms Rapid wilt/death. Needles yellow then brown. Lack resin. Branches dry, brittle. They snap rather than bend
Image from: http://www.extension.iastate.edu/Publications/SUL9.pdf
Beetle overwinters in pine trees -start emerge ~ May 1st. female male Images from: http://www.extension.iastate.edu/Publications/SUL9.pdf
*Lay eggs, (prefer drought stressed/dying) *Nematodes enter tree and feed on bluestain fungi. Lay eggs all season May 1 : adult beetles emerge Images from: http://www.extension.iastate.edu/Publications/SUL9.pdf Beetles feed in healthy trees Nematodes are inside the trachea (breathing tubes) of the beetle. Beetle carries up to ~80,000 nematodes
Egg-laying phase *Beetle larvae develop in the tree. *Larvae feed in cambium layer, then burrow deeper into the tree *Larvae turn to pupae *Nematodes are attracted to pupae *Pupae emerge as adults, and the cycle continues Image from: http://www.extension.iastate.edu/Publications/SUL9.pdf Feeding phase Nematodes leave beetles and enter tree through feeding wounds. Nemas eat plant cells, and tree dies
The nematode in the tree • Once in the tree, the nematode spreads around in resin ducts. Feeds on resin cells (healthy trees) or blue-stain fungi (in dead trees) • When food is running out, nematode seeks out the beetle. Nematodes produce 4th stage larvae which hitch a ride with the beetle. This larva is a “dispersal” stage, tolerates drying. (dauer larvae)
Nematode can’t spread by itself: it needs the beetle • Beetle can fly several miles • We can also spread nematode and beetle in nursery stock, firewood
Sanitation is Critical Component in Controlling Pine Wilt • Tree removal before April 1 • Reduces nematode and pine sawyer numbers • Don’t leave stumps • Root removal not necessary • Don’t stack wood. • Chip or burn dead trees. • Sanitation must be coordinated effort. • Pine sawyers strong fliers
Two new products for pine wilt • Greyhound and Pinetect • Both are 2% Abamectin • Contact companies (Rainbow Tree Care, Arborsystems) for more information • Need to be applied by trained treecare professionals
Injections • Not 100% effective • No curative activity • Carefully evaluate tree beforehand • Proper technique • Repeat every 2 years • Expensive