Peanut Burrower Bugs (Pangaeus bilineatus) have been collected and identified, by the Virginia Tech Insect Identification Laboratory, on the Tidewater AREC farm. Peanut burrower bugs are a subterranean pests that feed on pods and pegs of developing peanuts. Burrower bugs have most likely been around for a while but Lorsban (active ingredient is chlorpyrifos) was controlling their populations. Since the removal of Lorsban (chlorpyrifos) from market shelves, there are no effective chemical controls for producers. Damage caused by the peanut burrower bugs looks similar to stink bug damage. This damage is only seen when peanuts are shelled. The skin is removed at buying points by graders: The insect does not leave an indicator of damage on the shell of the peanut. Peanut burrower bug is more of an issue in hot dry years, and they are just as sporadic as southern corn rootworm.
In terms of prevention, there is no chemical control with the loss of lorsban. Some producers have gone back to using a moldboard plow and completely turning over the soil. Some producers have been planting earlier hoping for a thicker hull development earlier in the season. Damage is minimal in Suffolk, VA, but it is something to keep in mind.
Black light trap captures for corn earworm moths averaged 15 per night in Greensville and 10 per night in Suffolk this week. Here is the Table. Our adult corn earworm cypermethrin vial tests are at 20% survival for the 5 microgram/vial rate of this pyrethroid insecticide (n = 754 moths tested, Suffolk, VA). I’m sweep netting high numbers of corn earworm larvae in R5 soybean at our research center, along with an increasing soybean looper population.
Crawlers are the most vulnerable stage to control the Japanese maple scale under nursery conditions. Monitoring crawler activity throughout the growing season will aid to refine the timing of deployment of any control tactic.
Graduate student Mollie Wyatt (Virginia Tech, Entomology Department) took the lead on creating a video showing us the step-by-step process on how to do the ‘tape method’ for monitoring crawler activity for this pest in ornamental trees.
You can click on the link below to access to a short version of this video. You might need an actual computer to watch that clip. The full version will be posted soon on our VCE website. Stay tune! Funding to support this project was provided by the Southern IPM Center and USDA NIFA.
Black light trap captures of corn earworm moths decreased this week in southeast Virginia. Sara Rutherford in Greensville had 13 per night; Scott Reiter reported 7 per night (Prince George-Templeton) and 8 per night (Prince George-Disputanta); Suffolk dropped to 20 per night. Here is the Table. Scott was getting 2 to 8 larvae (mostly in the 0.5-inch size range, or 4th instar) in his soybean samples this week. I had larval numbers range from 1 to 10 larvae per 25 sweeps in untreated Suffolk and Greensville soybean. There is no substitute for scouting your fields. To calculate your thresholds, please see this online calculator
Black light trap captures of corn earworm moths increased this week. Sara Rutherford reported an average of 27 moths per night for Greensville; in Prince George, Scott Reiter had 13 per night (Templeton) and 18 per night (Disputanta); in Suffolk, we saw an average of 62 per night. Here is the updated Table
In our August corn earworm vial tests, 19% of moths survived the 24-hour exposure to 5 micrograms of cypermethrin. This is below our 10-year average of 32% survival.
The presence of corn ear worm moths in the blacklight traps have increased this week. Sarah Rutherford in Greensville (Jarratt) recorded an average of 13 moths per night; Scott Reiter in Prince George had 62 moths per night in Wells and 42 per night in Rosbicki; The Tidewater AREC entomology team recorded an average of 50 moths per night in Suffolk.
Corn earworm moth catches are starting to pick up in our black light traps, but at this point are still fairly low. Sara Rutherford in Greensville (Jarratt) averaged 6.8 moths per night; Scott Reiter in Prince George had 3 per night in Templeton and 1.5 per night in Disputanta; the Tidewater AREC entomology team (Benjamin McManaway and Gwenyth Gregory) captured an average of 4.4 moths per night in Suffolk. Here is the Table
Pheromone trap catches of corn earworm moths in Suffolk increased this week–we are using these moths as part of our insecticide resistance monitoring program. So far we have tested 76 moths, with 17.6% surviving a 24-hour exposure to cypermethrin (a pyrethroid insecticide).
Cereal leaf beetle, a pest of small grains, overwinters as an adult.
When temperatures warm, adults migrate to small grains to lay eggs; eggs are yellow-orange in color, usually in the midvein of the leaf, and may be single or several eggs end-to-end.
I saw a few eggs at our research center field today (March 9), they were a bit darker (and stickier) than their normal color. A female may lay 50 eggs. Larvae have orange-yellow bodies with dark heads and legs, but often appear as shiny black due to the covering of mucus and fecal matter they have on their body (they look like small slugs).
Larval feeding strips leaves of phytosynthetic tissue and can cause reductions in grain quality and yield. A temperature-based model developed using Virginia and North Carolina data shows that peak egg lay occurs at approximately 182 degree-days (using January 1 as a biofix; a lower development threshold of 8℃, and an upper development threshold of 25℃). With our warm February 2023 temperatures, we hit an earlier-than-normal peak egg threshold in Suffolk, VA on March 3 (I used the Tidewater AREC WeatherSTEM as my temperature source). The larval peak follows the egg peak by an average of 17.5 days, which would be the third week of March for Suffolk. It is important to note that the model states that extremely hot or cold years may affect its accuracy. Dominic Reisig (Professor and Extension Specialist, North Carolina State University) posted that the Salisbury, NC egg peak was predicted to occur on March 5-11, but a cooler forecast may push back the larval peak to the last week of March. As of March 8, Warsaw, VA is at 123 degree-days for cereal leaf beetle and the Eastern Shore has accumulated 119 degree-days.
To scout for cereal leaf beetle, inspect 10 tillers (stems) in at least 10 different sites. If you are seeing mostly eggs, you should scout again in 5-7 days when some have hatched into small larvae. The eggs may be parasitized. Both Virginia and North Carolina recommend an economic threshold of 25 eggs + small larvae (total) per 100 tillers. At least half of that 25 should be larvae. An insecticide spray, if needed, should target the newly-hatched larvae. Please refer to pages 4-44 and 4-45 of the Virginia Cooperative Extension 2023 Field Crops Pest Management Guide for additional information and spray recommendations. Another useful resource is a Journal of Integrated Pest Management article by Philips et al. (2011), Fifty Years of Cereal Leaf Beetle in the U.S.: An Update on Its Biology, Management, and Current Research.
Corn earworm (=bollworm) moth captures from southeast Virginia black light traps this week were 5 per night at Templeton (Prince George Co.) and 4 per night at Disputanta (Prince George Co.); Suffolk numbers averaged 45 per night. Here is the Table. In our pyrethroid resistance monitoring tests, the seasonal average is at 33% survival (n=565 moths tested).