Pine tree maintenance |

Pine tree maintenance

Richard Snell
Barton County Extension Agent

Unfortunately, there are a lot of dead pine trees still standing that need to be removed this spring to prevent further spread of the pine wilt disease. If the tree is totally brown, cut off a small diameter branch foot long section next to the trunk and bring it to our office to have it sent in for testing.

To refresh everyone’s memory, the pine wilt disease is caused by the pinewood nematode. This microscopic worm is transmitted from tree to tree in the spring and early summer by an insect called the pine sawyer. Once the nematode is inside the tree, it inhibits water movement and the tree dies, usually in late summer or fall.

The pine sawyer breeds in recently killed pine wood and emerges in the spring carrying the nematode. It then feeds on bark of small twigs in the crowns of healthy trees. It is at this point that the nematode moves into the fresh wound on the tree and starts the infection.

Pine sawyers are attracted to dead and dying trees in the fall to lay their eggs. The eggs hatch and the larvae feed on this wood, with adults emerging in the spring. Therefore, it is important to remove and destroy the dead wood in the spring before the insects emerge. We recommend this be done by mid-to late April. The dead wood can be burned, buried or chipped. Don’t save the wood for firewood and don’t leave stumps.