Pest News Update

Invasive Pest Found on North Carolina Soybeans Spreading Rapidly

Kudzu bug (aka bean plataspid, Megacopta cribraria Fabricus) has recently been confirmed on kudzu from several North Carolina counties where it was not previously found. In addition, it has been reported on a legume from the North Carolina Arboretum, although this has not been confirmed. Soybean is the main agronomic host for this insect, but it will feed on many other legumes.

This insect was found on flowering volunteer soybean plants on 10 June in Union county by a Wingate University researcher, Erika Scocco, collecting kudzu bug for a molecular study. This is the first confirmed sighting of this insect on soybean in our state. In North Carolina, the pattern of spread is mirroring that of South Carolina in 2010. This insect feeds on the stems and leaves, and may come into our soybean fields earlier, rather than later, during the season.

So far, kudzu bug has been relatively easy to kill with insecticides (except with neonicotinoids), but will often reinvade. A preliminary economic threshold, based on Georgia data, is one bug per sweep with large nymphs present, or three bugs per plant with large nymphs present.

We are tracking this pest and would appreciate you contacting Dominic Reisig (electronic mail at dominic_reisig@ncsu.edu; telephone at 252-793-4428 x133) if you find this pest in a non-confirmed county. If you could also provide GPS coordinates, as well as the plant on which it was found, it would enhance our ability to respond to this new threat. Please use caution not to spread this pest from field to field if you find it.

Although this insect sounds like a possible beneficial pest- eating Kudzu; it has been found on other legumes including desirable ornamental plants. So keep your eyes open!


ORNAMENTALS AND TURF

From: Steve Bambara, Extension Entomologist

Lightning Bugs Are Looking Good

For the first time in several years, most of North Carolina has had a reasonable amount of rainfall in the spring. This year the lampyrids (lightning bugs) seem to be off to a good start. Lightning bugs are beetles. Fireflies are, coincidentally, also beetles! Lightning bug adults produce a heat-free source of light through a biochemical reaction. The light flashes are used to attract mates. Different species have different flash patterns and are active at different times during the evening. What does this have to do with pest management? One of the many great aspects of lightning bugs is that the larvae of some species are predatory on snails and slugs!


Citrus Whiteflies on Gardenia

The citrus whitefly is a tiny, frosty white insect about 2 mm in length. It is not a true fly. Females insert their eggs into the lower surface of the leaves of gardenia and Swedish ivy. Soon the immature stages hatch into scale-like insects that suck sap from the lower leaf surface. They are often mistakenly reported as a scale. Look for ant activity, honeydew, or sooty mold on these plants. There is additional information in Publication AG-136, Insect and Related Pests of Flowers and Foliage Plants available on the web at Whitefly.

Citrus whiteflies suck sap from the plant and excrete honeydew, a sweet, sticky substance. Sooty molds go hand-in-hand with infestations of citrus whitefly. Sooty molds grow in the honeydew and cause infested bushes to become dull and dark. Horticultural oils should give some control of the citrus whitefly. Orthene is also effective. Imidacloprid would also be an effective systemic as a root drench.


Cicadas, Act II

Periodical cicadas were a big hit this spring across most of North Carolina. It is now time for the annual cicada to make its appearance. Already spotted, are the larger green annual cicadas that appear every year in low numbers. By now, most of you are familiar with cicadas. Every summer the chunky brown nymphs crawl from under the ground and perform a transformation as dramatic as the change of a chrysalis to a butterfly. Though the individual life cycle may last several years for the annuals, the entire population does not emerge in synchrony as do their famous earlier periodical cousins. You should now be able to enjoy their daytime buzzing and still hear yourself think.


For more information contact your local Cooperative Extension Center and ask for the Commercial Horticulture Agent.