Insect Pest - Other/Misc

IPM Threshold Guide for Agronomic Field Crops

Potato production in Maryland continues to grow and has more than doubled in the last 5 years, while in surrounding states it has declined. About 50% of the potatoes harvested in Maryland are for the fresh market while the other half goes for processing. Because of its value growers frequently apply pesticides too often in order to protect their investment. This often leads to the development of insect resistance, environmental contamination, worker and food safety concerns and poor management of pests.

Crapemrytle bark scale was first confirmed in Maryland in April 2020 by the Maryland Department of Agriculture. It was later found in Frederick and Carroll Counties. Monitor crape myrtles closely for this pest to limit the spread of the scale insect.

Potato leafhoppers Empoasca fabae started out showing up early in the season in our area in unexpected numbers and now they are showing up again in vegetables (eggplant and potato) fruit crops (raspberries) and hops where they are causing some problems (figs 1, 2, 3). Unlike earlier in the season when most of the leafhoppers were adults most of the ones found now are nymphs (fig 4).

Potato leafhoppers (Empoasca fabae) are a problem in nurseries on trees such as maples, redbud, and goldenraintree.

I do not usually look at hops very much as only a few farms have them, but they are becoming a bit more common in the last 10 years (Fig. 1). Visiting two farms withy hops I saw marginal leaf damage (Fig. 2) on some leaves (found some thrips too) and then marginal leaf scorch on others (Fig. 3). When looking on the underside of these leaf-scorched damaged leaves, I found many potato leaf hopper nymphs (no adults) (Fig. 4) on one farm and only a few on the other. Potato leafhoppers prefer warm, dry conditions and are common in southern states where they overwinter; leaf hoppers do not overwinter in our area.

There have been problems in our vegetable fields with three pests, which include striped cucumber beetles, leafhoppers and twospotted spider mites. I think most of the problems we are having with these three comes from our mild winter as each has had an outbreak population after a mild winter sometime in the last 12 years.

This Timely Viticulture article is on the periodical (17-year) Brood X Cicadas. The content includes the background, life cycle, damage, and the management of the emergence of the Brood X Cicada in the vineyard.

This season keeps with the weird and unusual with reports of grasshoppers causing damage in many different vegetables.

The cool, wet spring weather we have been experiencing favors slugs, so be on the lookout for slug damage. Slug damage may easily be confused for sap beetle feeding, but management of these pests is very different, so it is important to correctly identify the problem. Both pests can be common in matted row production. Authors: Sankara Ganesh, Maria Cramer, and Kelly Hamby, Department of Entomology, University of Maryland, College Park