Q&A With Seth Nagy- Carpenter Bees and Orchard Grass

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This week I want to share three questions we received at the N.C. Cooperative Extension, Caldwell County Center. I hope you find these questions and their answers helpful.

Question: What can I do about carpenter bees?

Answer: There are no “silver bullets” for preventing carpenter bees from drilling other than using non-wood composite building materials. Favored targets for the bees are areas such as fascia boards, porch rails & spindles. Some people use carpenter bee traps, which will catch some bees, but whether they control the bees is in the eye of the user.

Carpenter bee visiting a sunflower. (credit Jackie Nagy)

Carpenter bee visiting a sunflower. (credit Jackie Nagy)

Right now, carpenter bee activity is on the increase. The activity is mostly male carpenter bees. They have a white spot on the front of their head. They can not sting. Only the female carpenter bees can sting. The males are waiting for the females to emerge so they can mate with them.

Surface sprays are not truly effective because the insecticide breaks down too quickly to provide long term control. The best control is still swatting the bees with a badminton racket. It is fun, too.

When you do find carpenter bee holes, I recommend applying an insecticidal dust to the holes and then caulking them about 24 hours later. Remember, when you’re spraying/dusting a carpenter bee gallery, keep a safe distance between your face and any possible backsplash. Be equally careful if spraying up over your head. (The laws of gravity apply to pesticides, too!)

Question: Why does Orchardgrass only last two years in a hayfield before it seems to disappear?

Answer: This month an article entitled “Survey of Orchardgrass Persistence in the Mid-Atlantic States“ was published in the Crop, Forage & Turfgrass Management Journal. The article was from researchers at Virginia Polytechnic Institute and State University, or better known as Virginia Tech.

The conclusion that these researchers drew from surveying 53 orchardgrass hayfields was “Soil fertility does not appear to be the main driver of orchardgrass persistence problems in this region, as mean soil test pH, P, and K were found to be adequate relative to critical values. We suggest other variables, such as warmer climate or possibly cutting height management, may be playing a bigger role in explaining reduced orchardgrass persistence.”

This conclusion agrees with orchardgrass trials being conducted at the Piedmont Research Station in Salisbury, NC. At the station, orchardgrass fields are now entering their fourth year. These fields are persisting very well and they look great. It is interesting to note these fields are cut at a height of 4 inches. This is higher than most hayfields are cut.

Orchardgrass trial plots at the Piedmont Research Station in Salisbury, NC. (Credit Stephanie Sosinski)

Orchardgrass trial plots at the Piedmont Research Station in Salisbury, NC. (Credit Stephanie Sosinski)

One thing the researchers from Virginia Tech did not consider is that older sickle bar hay mowers do not cut the grass as short as the newer disk mowers. This slight change may be enough to explain why orchardgrass does not persist as well as it did 25 or 30 years ago.

Question: What is the term used to describe when field crops are laid flat by storms &/or wind?

Answer: The term is lodging. When crops fall over, farmers say they “lodged”.

For answers to your agricultural questions, call the N.C. Cooperative Extension, Caldwell County Center at 828-757-1290 or visit us online anytime.

N.C. Cooperative Extension is open to everyone. We strive to provide research-based and unbiased information.