 | Field and Forage Crops |
 | Ornamentals and Turf |
From: Jack S. Bacheler, Extension Entomologist
We appear to have entered one of those times that in which the cotton crop varies widely from area to area depending on planting date, amount of thrips damage, and whether a particular area has received timely rainfall. Some cotton has been beyond the thrips susceptible five true leaf stage, while other cotton is still struggling and has been sprayed for the third time for thrips. In most of the samples sent in to the clinic last week from problem cotton fields, the sheer number of tobacco thrips adults and immature thrips has been the main problem. However, the hard-to-control western flower thrips is still part of the problem in some fields in dry areas of the state, though counts have been generally down the past few days.
Hopefully, by this time next week, thrips damage will be over for all but a few acres and we can get a little breathing room before the post-bloom bug pests arrive. In the meantime, spider mites, cotton aphids and occasional plant bug infestations are all possibilities, although plant bugs are rarely a problem here in pre-bloom cotton.
Scouts should watch for light speckling on cotton foliage that indicates the beginning of spider mite infestations. As mite levels build, leaves become increasingly red toward the midveins. In our area, because a parasitic fungus often comes to the rescue, we do not recommend treatment for mites until the infestation is present throughout most of the field and bottom leaves are beginning to fall off some plants. Fortunately, mites are easy to identify under even a 10x hand lens.
Cotton aphids are easy from a scouting perspective because it takes a very high population here to justify treatment. Drooping plants and the presence of honeydew (that is, shiny leaves) are often the first visible sign of cotton aphids. The tricky part of evaluating an aphid infestation is to take into account the degree of wasp parasitism and the presence of the aphid fungus.
To date, a few additional infestations have been reported, and only a few indications of cotton aphid buildups. We will have more information on these and other pests in the coming weeks.
From: Stephen B. Bambara, Extension Entomologist
Slugs can be a problem in greenhouses and some gardens. Adult slugs (image by James R. Baker) are soft, slimy, slender animals more closely related to clams and octopi than insects. Slugs have stalked eyes and two small feelers. Some species grow to three or more inches long. They use rasping mouthparts to scrape away vegetable material. This may leave ragged shaped holes in leaves of tender plants (mage by James R. Baker). Slugs are active at night and during cloudy, warm weather. During bright warm days, slugs usually hide under boards, stones, debris or tunnel into the soil.
Slug populations can be reduced by keeping raw composting materials away from the garden, "trapping" and destroying slugs under rocks or boards, or destroying them at night. Be careful not to over mulch where the mulch never dries. There are a few chemicals listed for slug treatment, but read the label carefully to determine if they are suitable in your garden or around pets. A saucer of beer is often suggested as a trap, but most experts feel that beer is better used as intended.
For more information on slugs and snails, see Ornamental and Turf Insect Note No. 22 at http://www.ces.ncsu.edu/depts/ent/notes/O&T/flowers/note22/note22.html.
The redbay ambrosia beetle, Xyleborus glabratus Eichhoff, was first detected in the U.S. in a survey trap in Georgia in 2002. It now exists from Florida to South Carolina on redbay and sassafras. Not enough is known about this ambrosia beetle, but its behavior seems very similar to the Granulate (Asian) ambrosia beetle. This beetle also makes "toothpicks" and is thought to vector a wilt disease (wilt symptoms of redbay and stained sapwood of redbay; images from A. E. Mayfield III and M. C. Thomas). Please report any wilting or bark beetle activity on redbay or sassafras so it can be checked. For more information, see the Florida Department of Agriculture and Consumer Services’ Pest Alert at http://www.doacs.state.fl.us/pi/enpp/ento/x.glabratus.html.
From: Christine A. Casey, Extension Entomologist
I am writing to let you all know that I will be leaving North Carolina State University at the end of June, with my last day on June 22. The limited research funds available for work in ornamentals have made establishing a solid program very difficult, so I have decided to pursue a career in my other area of interest, veterinary medicine.
The University plans to re-fill the position immediately. In the meantime, Steve Bambara will once again bear the burden of doing the job of two people. I have prepared several presentations for use by county Extension agents in the interim. They are Nursery Insect and Mite Pests, Borers, Greenhouse Insect and Mite Pests, Landscapes and Biological Control, Ambrosia Beetles, Scale Insects, and Pesticide Modes-of-Action. The ones with information for which you may not be familiar have notes to accompany them. Please contact Steve Bambara if you need any of these presentations.
It has been a pleasure working with you. Thank you for all of your hard work and good luck with your future program.
Editor’s Note: Thank you Christine for your service to the Ornamental Plant Industry and to North Carolina State University, and for your valuable contribution to the North Carolina Pest News. We wish you the best in your new endeavor! – Steve Bambara and Steve Toth, Extension Entomologists, North Carolina State University
Employment and program opportunities are offered to all people regardless of race, color, national origin, sex, age or disability. North Carolina State University, North Carolina A&T State University, U.S. Department of Agriculture, and local governments cooperating.
Last modified on June 18, 2007 by Stephen J. Toth, Jr.
