Beneficial Insect Populations

I was looking at peanuts yesterday for insects. I did see some alfalfa leaf hoppers, but no damage from immatures. I also saw a velbetbean caterpillar moth. They are usually later. So, we do need to scout and make sure our populations are at treatable thresholds before we spray. We have many beneficial insects that help us out in the field also. UGA Extension Entomologist Dr. Phillip Roberts says we should try to avoid scheduled applications of insecticides since unnecessary applications can not only be costly, they can also destroy beneficial insects. This is why we follow thresholds when treating insects. Here are some beneficial insects I’m seeing in the field now. Some photos I took elsewhere.

Assasin Bugs – I did not get this picture from the field yesterday, but I did see some assissin bugs in my sweep net. They have a long beak which is used to inject an enzyme into their prey. They then suck the body fluids out. They are in the same group of “kissing bugs” (Assissin bugs, wheel bugs, damsel bugs, leaf-footed bugs). They feed on soft-bodied prey like mosquitoes, flies, cucumber beetles and caterpillars. The nymphs (immatures) have their abdomen point upward like in the photo below.

Immature Assissin Bugs

Immature Assissin Bugs

Spined Soldier Bug - NymphSpined Soldier Bug – Here is a nymph from a spined soldier bug. They are a medium-sized predatory stink bug which preys on caterpillars and larvae of beetles. They can be hard to identify, especially at immature stage. If you see an instar that is red and black, those are younger instars. This is closer to a 5th instar where the wing pads are prominent, and the head and thorax become mottled with brown. The abdominal markings are white or tan, and black. Also, their mouthparts are larger than stink bugs’s mouthparts and are close to the width of the antennae.

Minute Pirate Bug

Minute Pirate Bug

Minute Pirate Bug – I saw this pirate bug near a cotton square and looked like plant bug. Plant bug is actually in a different family, but share many similar characteristics. Pirate bugs are generalist predators. Adults and nymphs feed on insect eggs and small insects such as psyllids, thrips, mites, aphids, whiteflies, and small caterpillars.

Braconid Was Pupae

Braconid Was Pupae

Braconid Wasp – In the peanuts I looked at Thursday, I saw what looked like ‘fuzzy rice’ on a few leaves. These are the cacoons of a pupating parasitoid wasps in the Braconidae family. Former Seminole Ag Agent Rome Ethredge showed this to me while training in a field. I feel like I see them all the time now. These wasps are parasites of aphids and caterpillars. A female wasp can attack hundreds of aphids in a two week span.

Lady Beetle Larvae

Lady Beetle Larvae

Lady Beetle – I’m seeing quite a few lady beetles in all fields. Unlike the pirate bugs, beetles have a complete lifecycle (egg, larvae, pupae, adult). Here is the larvae of a lady beetle. Larvae are usually carrot-shaped, warty and have well developed legs. The most commonly seen are the pink and convergent lady beetles. They are predatory and feed on a variety insects including mites, scales and aphids. Below is a photo of lady bug pupae on a cotton leaf from last year.

Lady Bug Pupae

Lady Bug Pupae

Lacewing Egg

Lacewing Egg

Green Lacewing – This is the egg of a green lacewing in the bottom of a cotton leaf. There are many species of lacewings, but green is most common. The eggs are often found on plants and are easily recognized since they are attached to a long, slender silken stalk which holds them above the surface. The larvae are sometimes called “ant lions” and are predators. They eat many small insects as they grow ranging from leafhoppers, scale insects, mites and also aphids. I took the picture of an “ant lion” last year eating a sugarcane aphid on grain sorghum.

Immature Green Lacewing - Antlion

Immature Green Lacewing – Antlion

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