No. 14/August 14, 2009

Scouting Watch
Magnolia scale and white grubs are the subject.

Zimmerman Pine Moth
Zimmerman pine moth is a common trunk and scaffold branch borer in Scotch, Austrian, and red pine in Illinois. It is a shoot tip borer in Eastern white pine.

Tar Spot of Maple
Tar spot of maple is caused by fungi in the Rhytisma genus, Rhytisma americanum (as in the image), R. punctatum, and R. acerinum.

Time to Test for BLS
Bacterial leaf scorch (BLS) is a disease with a name that definitely understates the impact on infected trees. It causes far more than leaf scorching. The bacterial pathogen can slowly kill mature trees in 8-10 years.

Rose Rosette
Rose rosette is a lethal disease of roses that may look very much like chemical injury from a plant growth regulator herbicide.