102 articles tagged "Insect and Mite Management".

In the past two weeks we have heard reports of the Squash vine borer (Figure 1) being spotted in some local gardens. This pest of cucurbit crops tends to be sporadic in our region; you are either battling it every year or it hardly makes an appearance. The squash vine borer is a member of the clear-winged moths, a unique group of moths that are active during the daytime. They are very beautiful with their bright colored orange tufts of hair. At this point in the season, we are encountering with the second generation in Indiana. The larvae feed in the ripening fruits (Figure 2). You can find holes in the fruit and sawdust-looking frass (excrement) indicating larval infestation. If you are planning to treat your crop, you need to target applications before those eggs hatch so that the larvae will ingest the spray upon hatching as they attempt to[Read More…]

After weeks of successive trap catches in the double digits, our recent catches have gone down. Be sure to check the CEW trapping website for updates daily. At this point in the season, when field corn is in the silking stage, the threat to sweet corn, and potentially hemp, goes down. The current action threshold is 10 moths in the trap per night. Spray decisions should be made based on the closest trap location. In the table online, if no value is entered, it means the trap has not been emptied. A zero will be present in the data table if the trap was checked and there were no moths present. As field corn dries out and is no longer silking, the threat to flowering hemp and silking sweet corn goes back up. The trap catch threshold lowers to 1 moth per night. Closely monitor your crop and the surrounding[Read More…]

While we might be struggling with the heat and lack of rain, there is one pest that is loving it, Mites! Now is the time to be on your toes watching out for this pest. Early detection and treatment are key. In protected environments prevention and early intervention are especially important; In the field, heavy rains can help knock these pests back. Two-spotted spider mites (TSSM) are one of the most common mite pests on vegetables. TSSM occur throughout the world. They are known to feed on over 300 plant species, including tomatoes, cucumbers, melons, grapes, apples, and a variety of common flower and weed species. They disperse by walking or flying on the wind currents. The adults are a pale green to yellowish color, or almost appear translucent, with two black spots on their back. Eggs and nymphs are present and overlapping with adults. The eggs are very small[Read More…]

The Purdue Extension Entomology Vegetable Team has a new website available for you to stay in touch and access resources for pest management in your vegetables, wherever and however you grow them! It is also the place to stay updated with the CEW trapping for 2020 by following the page to this location. Check it out! https://extension.entm.purdue.edu/veg/

Squash bugs are a pest of cucurbit crops and can sometimes go unnoticed until late in the season when the local populations have built up and you see them in high numbers (Figure 1) attacking the fruits of your crop. Squash bugs are similar in appearance to stink bugs but smell much more pleasant (in my opinion) when you squish them. They feed on all parts of the plant (leaves, stems, fruits) with piercing-sucking mouthparts and inject toxins in their saliva that can lead to localized wilting and crisping of leaves (Figure 2). Squash bugs are particularly problematic in pumpkin and squash (Figure 3) but can also be quite damaging in cucumber. The adults (Figure 4) are more difficult to control with insecticides, therefore best management practices should target the young nymphs, soon after hatching. The eggs are easy to identify. They are copper-colored and laid on the underside of[Read More…]

Figure 1: Striped cucumber beetle seen feeding on newly transplanted watermelon. The first-generation beetles can occur in high enough numbers to stunt plant growth or kill the seedling outright.

While in your fields in the last week you may have noticed fewer striped cucumber beetles on the leaves and stems of the growing cucurbit plants (Figure 1). This is because there are two generations of this pest in Indiana; the 1st generation adults that overwintered in the field have mated and left behind their eggs in the soil around the crop roots. When these eggs hatch the cucumber beetle larvae will feed on plant roots until they pupate into adults and emerge as the second generation typically in early July. Fields in northern Indiana will likely be 1-2 weeks behind on the second-generation emergence compared to southern regions of the state. This means that while you still may see adult striped cucumber beetles in your vegetable fields, they are likely not going to be found at high enough populations to cause economic damage (1 beetle per plant in cucumbers[Read More…]

Figure 4. Ladybeetle, Orius nymph, lacewing larva, syrphid fly larva, and nabid bug predators of aphids found in strawberry plot. Photos by John Obermeyer and Laura Ingwell.

Aphids have been a particularly challenging pest to get under control in our high tunnel strawberries this year. They quickly colonized the strawberries we had growing all winter and took off as the weather warmed (Figure 1). In my first attempt to knock them back I introduced 2,000 lacewing larvae (22-Apr), too little too late. I decided to take the ‘opportunity’ at hand to evaluate four OMRI approved insecticide options. Applications began when populations were much higher than what growers should tolerate, so I would anticipate you would see even better results if you intervene at the first signs of infestation. Table 1 shows the products, active ingredient (A.I.), application rate and dates of applications. The change in aphid populations over the course of this trial are shown in Figure 2. In entomological tradition, I surveyed the aphid population prior to treatment (1-May) to get a baseline. As you can[Read More…]

Info about the culprit insect: Cutworms are the larval (caterpillar) stage of moths in the family Noctuidae, which typically fly at night. Although the adult moths are not damaging, the voracious larvae can be! The caterpillars typically hide during the day and emerge at night, curling around young, tender plants to feed. How many kinds of cutworms are there? There are several species of cutworms, but you are most likely to encounter one of four species of cutworm in Indiana: either the dingy, variegated, or clay backed cutworms, which overwinter as partially grown larvae, or the black cutworm, which does not overwinter in the Midwest, but migrates back each year. The black and clay backed cutworms are leaf feeders and plant (stem) cutters, while the dingy and variegated cutworms are mainly leaf feeders that rarely cut plants at or below the ground level. What crops do cutworms attack? Cutworms are[Read More…]

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