Potato leaf hopper counts seem to be remaining constant, staying below threshold in alfalfa fields. Other insects, such as Japanese beetles in sweet corn, or grasshoppers in soybeans, are not holding steady, instead, we are seeing increasing population numbers and an increase in foliar feeding activity. Corn fields have seen an uptick in activity and feeding from armyworm.
In some fields, where moisture seemed to be limited due to spotty rain showers, we have started to see some nutrient deficiencies, more specifically potassium. Adequate soil moisture is key to have nutrient uptake through mass flow, and when nutrients like potassium are not taken up in adequate amounts, the effects of lack of moisture can compound.
High tunnel tomatoes were one of the areas of focus for disease development this past week. Many high tunnel tomatoes are currently experiencing cases of leaf mold. As a side note on high tunnel tomatoes, we did observe a thrips outbreak in a high tunnel, where heavy feeding by the thrips was causing significant discoloration on the foliage and stunting of the plants. Peppers took up the other focus with disease development, mainly due to favorable conditions for bacterial diseases to manifest.
Flea beetles seemed to make a comeback this week. Several fields of cole crops were over threshold for flea beetle counts. Japanese beetles are continuing to feed in the majority of the crops planted in the area. Other insects like squash bugs are starting to be found more frequently, specifically in early planted summer squash.
Sticking with cucurbits, we are starting to find spots of powdery mildew in plantings of zucchini and yellow squash. It is important to scout your crops and look for powdery mildew, especially if you have succession plantings of young cucurbit crops nearby. Powdery mildew is easily spread onto younger plants, so it is recommended that you keep up with spraying for powdery mildew and terminate the older infected plantings once you are done harvesting.
Small Fruit and Orchards
First and foremost, we have found spotted winged drosophila in our area. The threshold for SWD in small fruit is 1 fly. Since we are now finding adults, we encourage growers to also do salt tests on the berries to check for larvae.
Wooly apple aphids continue to show up in the several apple orchards in the area. These are a tough pest to get under control due to their protective waxy coating.
OFM counts in some peach blocks were above threshold for the first time in several weeks. OFM counts remained well below threshold.