Crops Blog

Agronomic Crops > Crops Blog > Posts > Insect Pheromone trap catches across Alabama – July 18, 2015

(Numbers are color coded to show relative activity of moths using total trap catches for various locations. We use sticky wing pheromone traps with lures at each location. Red means very high activity and green mean low activity for the location.)

 Beet armyworm

BAW map 7-18-15.jpg


Beet armyworms (BAW): Has 5-6 generations in the south. Host plants include bean, corn, cowpea, eggplant, pea, pepper, potato, tomato, and many other vegetables. Field crops may include corn, cotton, peanut, sorghum, and soybean.

 

Pest status: BAW moth numbers have been consistently high – south Alabama has almost 9 times greater activity than the north. On a statewide basis, the average trap counts have increased from 0.2 moths per trap in May to 26.5 moths per trap in July (53x increase). Based on peanut and vegetable scouting, BAW caterpillars are showing up on crops like peanuts and tomatoes - producers elsewhere may see overlapping generations at or above economic threshold levels. While there is an economic threshold for the insect on peanuts (four or more caterpillars per foot of row), even a few egg masses and caterpillars can be a major threat to vegetable crops.

 

Fall armyworm

FAW map 7-18-15.jpg

Fall armyworm (FAW): Has 4-5 generations in the south – migrates upward from FL and populations get worse mid- to-late-season on specialty or row crops. Prefers to feed on grasses then move to various row crops and vegetables that include fruiting crops.

 

Pest status: Fall armyworm moths have increased from slowly – populations seem to be more active on crops in Central Alabama compared to any other locations. On a statewide basis, the average trap counts have increased from 0.1 moths per trap in May to 2.8 moths per trap in July (28x increase). It appears that we are detecting a high second or third (overlapping) generation in the traps. Continued hot dry weather can make populations to increase – peak is usually in July or August in row crops/vegetables. We have already seen a low number of caterpillars in peanuts and vegetable crops (below economic threshold).


Hay and livestock producers are encouraged to visit http://www.aces.edu/anr/forages/Management/documents/FallArmywormMap.php for update about armyworms (maps prepared by Dr. Kathy Flanders). 

 

Soybean looper

SL map 7-18-15.jpg

Soybean looper (SL): Infestations happen from migrating populations or moths may be moved by weather systems. SL attack soybean and peanuts among other row crops. Also attacks many summer vegetable crops during late season.

 

Pest status: We have seen a spike in SL moth activity and in some southern counties of Alabama growers may find the caterpillars more readily compared to northern areas. On a statewide basis, the average trap counts have increased from 0 moths per trap in May to 1 moth per trap at about 50% of the monitored location. It appears we are in a late second generation of these insects but we have not seen many caterpillars in peanut fields. Moth activity usually peaks in July and August with a rapid increase in the number of caterpillars.

 

Corn earworm

CEW map 7-18-15.jpg

Corn earworm (CEW): Has about 5-7 generations in the south. Corn, tomato and cotton appear to be favorite crops among numerous others row and horticultural plants that may also be attacked.

 

Pest status: Moth numbers appears to be fairly low in most of the monitored location, the average moth numbers have increased from zero in May to 0.5 per trap in July. It appears we have detected a low third generation of the CEW moths, but we are not sure. In Alabama, peak CEW activity usually happens in late July and August – so remain alert for CEW and tobacco budworm mixed populations. Tomatoes are a favored host for CEW moths to lay eggs if corn is unavailable – so vegetable producers should watch out and scout intensively to detect this pest at the earliest!

 

Tobacco budworm

TBW map 7-18-15.jpg


Tobacco budworm (TBW): Has about 5 generations in the south. Host crops include cotton, soybean, and peanuts among others. May also attack vegetables as pea, pepper, pigeon pea, squash, and tomato.

 

Pest status: We have detected TBW moths at nearly 50% locations out of the 17 monitoring sites. Although we do not see a clear trend for active TBW populations, locations in central Alabama and the north (Cullman) had a sharp increase with a possible second generation becoming active statewide. On a statewide basis, the average moth numbers have gone up slightly from 0 moths per trap in May to 0.6 moths per trap in July. These insects are difficult to kill with synthetic pyrethroids – so identify caterpillars carefully before you spray! Seek help from the Insect Diagnostic Lab or a Regional Extension Agent.

 

 Lesser cornstalk borer

LCB map 7-18-15.jpg


Lesser cornstalk borer (LCB): 3-4 generations may occur. Prefers various legume (including peanuts and soybeans) and grassy crops. In peanuts, LCB damage can cause rapid yield loss along with severe crop contamination during hot dry weather conditions. This insect can also devastate large acres of soybean fields under favorable conditions.

 

Pest status: LCB moths have been detected in very high numbers from peanut fields. On a statewide basis, the average moth numbers have increased from 3.7 per trap in May to 162.4 per trap in July (44x increase). It appears we are experiencing a late second generation of moths at many locations in Central and South Alabama. Crop damage from caterpillars usually follows prolonged hot dry weather. In peanuts, LCB infestations can dramatically increase the risk of aflatoxins.


Squash vine borer

SVB map 7-18-15.jpg

Squash vine borer (SVB): Has one to two generation per year depending on location. Moths are day-flying and they can migrate long distances during early spring to find host plants. Moths look like wasps and lay eggs on the stem close to the soil. Caterpillars cannot be killed once they burrow inside the plant stalk, so use pest prevention tactics. Vines must be protected using insecticides or with insect netting to reduce egg laying.

 

Pest status: Moth activity is high in about 80% locations (action threshold is one moth on organic vegetable farms) with average moth numbers increasing from 0.6 per trap in May to almost 9 per trap in July. It appears we are experiencing the second generation with sharp increase in numbers due to overlapping generations. On squash, producers/gardeners in high pest pressure areas may be able to see excreta (due to live larva) at the plant bases. 


Acknowledgement: The data visualization maps above have been developed using MyTraps.com (Spensa Technologies, IN). We appreciate the assistance provided by Regional Extension Agents and producers for data collection/pest monitoring. Many thanks to Luke Knight and Lucinda Daughtry (Undergraduate Project Assistants) for assistance in insect monitoring.

 

For IPM questions, please call Ayanava Majumdar, 251-331-8416, bugdoctor@auburn.edu or use the resources below.

Vegetable IPM: www.aces.edu/vegetableipm

Peanut IPM: www.aces.edu/peanutipm

Facebook pages: Alabama Vegetable IPM or Alabama Peanut IPM 

Alabama IPM Communicator newsletter: www.aces.edu/ipmcommunicator


Comments

There are no comments for this post.