No. 14/August 29, 2018

Zimmerman Pine Moth
Zimmerman pine moth (Dioryctria zimmermani) is a borer that injures tree trunks and scaffold branches.  These insects commonly feed on Austrian, red and Scotch pines in Illinois, causing dieback in branches and twigs.  Zimmerman pine moth injury can be identified on the trunk as crusted areas of white pitch 1 to 2 inches in diameter or white cones of pitch that are about 1 inch in diameter.  Terminal leaders that are heavily infested may also begin to bend downward like a hook.

Bur Oak Blight
Be on the lookout for bur oak blight. We have had a few questions come in regarding bur oak blight. This potentially serious fungal disease only affects certain types of bur oak trees. The fungal pathogen that causes bur oak blight was first identified in Iowa and has been reported in almost every county in Iowa and Minnesota. The disease was first reported in Illinois in 2012. Since then, the Plant Clinic has received symptomatic samples almost every year. Initially, the disease was only observed in northern counties and one far western county (Hancock). In recent years, we have received samples from central portion of the state. These samples were either confirmed or highly suspected of infection with the bur oak blight pathogen.

Safety While Pruning Trees--Not for the Faint of Heart
We are nearing the end of the summer season, as our plants wind down, it is time to start looking at what plants need to be trimmed or completely removed. Maintaining trees is important for economics as well as aesthetics. Trees increase a home value, provide shade and also beautify a landscape. When it comes to trimming trees, it isn't easy. Simply put, just because you have a truck, ladder and chainsaw, doesn't mean that you are a tree trimmer. There are several precautions that should be taken before climbing a ladder.