Extension Report

Baldwin County Extension Office

302A Byrne Street

Bay Minette, AL  36507

Telephone (251) 937-7176 or

928-0860/943-5611 ext. 2222

FAX (251) 937-7285

Ayanava Majumdar

Extension Entomologist

Peanuts & Vegetables

November 3, 2009

Alabama Cooperative Extension System (ACES) is committed to providing you research-based information and technical support for your farming operations. In the last news release that was published in August 2009, I emphasized the importance of Integrated Pest Management (IPM) as a decision making tool that takes into account integration of many insect pest management tactics such as cultural control, biological control, chemical control, etc. I also provided a description of a new Extension IPM program, conducted by a team of twelve Extension personnel, which consisted of an intense insect monitoring program using pheromone traps. The ultimate goal for this IPM project is to motivate farmers and gardeners to initiate or increase the usage of modern insect trapping kits that are cost-effective and easy to use. The Extension IPM project was operated in 14 counties in order to generate a representative sample (i.e., an estimate) of insect activity in Alabama. Results from the preliminary 2009 project are very enlightening and reported herein. Since capital and human resource limitation does not allow ACES to conduct the project in every county of Alabama, it is YOU who has to eventually adapt the new technologies to your farm in order to sustain the crop production levels.

Common wing traps, that are available from many vendors over the Internet, can be used for monitoring a wide range of moths. Corn rootworm traps (in picture)

are more sophisticated yet easy to operate and virtually maintenance-free. In the project, several types of traps were placed along the grassy field edges near peanut and vegetable farms for season-long insect monitoring (June to October). As of this date, the IPM team project has identified and accounted for over 8,500 insect specimens collected from 600+ samples from various kinds of traps. More specifically, about 3,586 lesser cornstalk borers, 1,386 fall armyworms, 1,377 beet armyworms, 393 southern armyworms, 589 corn earworms, 342 tobacco budworms, 230 soybean loopers, 223 cabbage loopers, 125 black cutworms, 65 diamondback moths, and 266 corn rootworms were collected statewide; these numbers give you an idea about the species presence and effectiveness of traps in reliably detecting closely related insect species such as the corn earworm (CEW) and tobacco budworm (TBW). Low insect numbers in traps do NOT mean that the insect is inactive; those numbers may have been influenced by weather patterns, trap type and placement method, lure quality, and pesticide usage in the sampling area. Peanut producers should note that chemical control recommendations for CEW and TBW are different (due to differential response to insecticides; refer to Alabama Peanut IPM Guide ANR-500); hence, knowing the correct insect species present in the field is vital in choosing correct treatment. Similarly, for vegetable producers, correctly differentiating armyworms from cutworms using pheromone traps can help in making informed IPM decisions (refer to the Southeastern Vegetable Crop Handbook). Using insect traps in conjunction with actual crop scouting could reduce ‘surprises’ and crop failure due to delayed action. 

On the basis of average insect numbers per trap over the entire season, Baldwin County had the highest activity of beet armyworms at 49 moths per trap (MTP), fall armyworms at 48 MTP, cabbage loopers at 12 MTP, and soybean loopers at 15 MTP. Mobile County had the highest activity of southern armyworms at 15 MTP, diamondback moths at 18 MTP, and lesser cornstalk borers at 143MTP. Henry County had the highest activity of tobacco budworms (20 MTP) and black cutworms (4 MTP) with peak in June and July. Chilton County had the highest activity (25 MTP) of corn earworms with peak in early August-September. Cullman County had unusually high corn rootworm activity (28 MTP) in early July which was a unique finding. Tomato pinworm and stink bugs were detected in very low numbers (data not shown because it probably misrepresents actual population in the crops). Peanut, corn and soybean producers across the southern Alabama counties should remain on high alert in 2010 for lesser cornstalk borers (LCB) since IPM traps have detected unusually high moth activity in ALL the surveyed counties. LCB injury is favored by dry hot summer and sandy soil; therefore, producers in such areas should closely monitor their crops for early damage symptoms such as sudden wilting of plants (cut open the stem and root or turn over the soil below plants to find the larvae). Statistical analyses of insect numbers and weather data (from www.awis.com) for five Alabama counties provided further insight regarding insect behavior. Insects are cold blooded animals; hence, weather has a strong effect on their behavior. Rain days, which is the number of days rainfall exceeded 0.1 inch, has a significant positive correlation with the activity of armyworms, loopers, LCB, and corn rootworms. Temperature has an inverse relationship with the activity of corn earworm and tobacco budworm, which means that high temperatures could lower insect numbers in traps by reducing moth flight. These observations should be considered preliminary because sample sizes were small in 2009. Further research is needed to substantiate findings reported herein. Data from multiple years can assist ACES to develop site-specific recommendations using insect forecast models that can predict insect outbreaks based on trap catches and weather patterns. For queries about this and other entomology projects in peanuts/vegetables, please call me 251-331-8416 or email bugdoctor@auburn.edu. You can also call the toll free IPM hotline 1-800-446-0375. For reading the 2009 Insect Pest Advisories, please visit http://tinyurl.com/yga7q8x.

Email address: azm0024@auburn.edu

Phone: 937-7176 or 943-5611, ext. 2222

The Alabama Cooperative Extension System (Alabama A&M and Auburn Universities) in cooperation with the U.S. Department of Agriculture is an equal opportunity educator and employer.