Clinic Update: Late Spring Samples Submitted to the Plant Diagnostic Clinic

The following is a summary of the types of samples submitted to the plant diagnostic clinic over the past month. We have received samples from several types of trees. We had decline of white pine in high pH soils, maple tip borer damage on silver maple, anthracnose on red maple, scale on redbud, weather-related injury on arborvitae, and galls on hickory. Although samples were not submitted to the clinic, there have been many reports of anthracnose on sycamores and ash trees throughout much of the state. I have also observed a twig blight on callery pears in the Columbia area probably caused by fireblight.

Orange rust of brambles. Photo by Simeon Wright

From ornamentals, we have received flats of vinca with Rhizoctonia web blight, hostas with symptoms consistent with viral infection, hostas with herbicide injury, hostas with wind and sun-burn, and peonies with cold temperature injury. I have also received several inquiries about an azalea problem that is probably azalea leaf gall.

From fruit and vegetable crops, we have received peach samples with peach leaf curl, elderberry with severe insect damage, possibly caused by sawfly larvae, and blackberry with orange rust. Among vegetable samples, we have received gourd seedlings infested with fungus gnat larvae, and tomatoes with leaf mold.

Peach leaf curl. Photo by Simeon Wright

In addition we have received submissions of several insect samples including subterranean termites, carpenter ants, ordorous house ants, larder beetles, and pine tip moth.

We look forward to receiving your samples. Please refer to the sample submission section of our website for more information on sample submission.

Simeon Wright, Plant Diagnostic Clinic