The following are highlights and updates about samples and questions recently received in the Plant and Insect Diagnostic Clinic. Visit the PIDC's Facebook page to ask questions and for updates and more pictures.
Samples of cucumbers have increased in the last 2 weeks. We have confirmed fungal disease like Alternaria leaf spot and anthracnose, as well as vascular diseases such fusarium wilt. Management of foliar disease in the home garden and in commercial field requires a combination of sanitation practices, crop rotation, planting resistant varieties, reducing moisture by watering the crown of the plant (drip irrigation systems) as opposed of the foliage, and preventive fungicide sprays.
- For home gardeners: Diseases of Cucurbits, Anthracnose.
- For commercial producers: Midwest Vegetable Production Guide for Commercial Growers 2016.
Cicada killer wasps have been causing worry across Iowa. These large wasps look intimidating, but they are not aggressive and stings are very uncommon. The female digs out a nest in the soil, often at the edges of sidewalks. See below for a picture of a cicada killer nest. See the Clinic website for more information.
Lace bug damage is obvious on some of their favorite plants. I have noted damage on sycamore, oak and serviceberry.