Author Archives: Sean Malone

Corn earworm moth black light trap report for August 23, 2018

Average nightly corn earworm moth captures for local black light traps this week were as follows: Chesapeake=8.0; Dinwiddie=42.6; Hanover=3.4; Isle of Wight=0.9; Prince George (Templeton)=1.3; Prince George (Disputanta)=3.3; Warsaw=6.6; Southampton=0.9; Suffolk=33.0; and Sussex=1.9

Here is the link to the data table:  BLT_23_Aug_2018

Thanks to Watson Lawrence, Mike Parrish, Laura Maxey Nay, Livvy Preisser, Scott Reiter, Mary Beahm, Neil Clark, and Dwayne Sanders for their reports!

Black light trap and vial test update for August 2, 2018

Corn earworm moth captures in black light traps continued to climb this week–please see the attached table (pdf document) for more details: BLT_2_Aug_2018

We have tested 246 corn earworm moths in our vial tests this season, with an average of 15% surviving a 24-hour exposure to the pyrethroid insecticide cypermethrin at 5 micrograms per vial. The line graph is available here: vial_tests_2_Aug_2018

At our research farm in Suffolk this week, we have been finding bollworm eggs in cotton terminals with some small larvae on squares and bolls. Please be sure to scout your fields!

2018 survey of field corn for corn earworm larvae

Statewide, approximately 18% of ears were infested with corn earworm larvae. Corn is considered a nursery crop for corn earworm, allowing the pest to complete a lifecycle and then move on to other crops such as soybean, cotton, and peanut in August. There is a linear correlation between the infestation level in corn and the amount of soybean acreage that gets treated with insecticide for this pest. Please see the attached pdf for more details: CEW_survey_results_2018

Corn earworm moth report for July 26, 2018

Black light trap captures of corn earworm moths in Suffolk really jumped this week, averaging 30 per night (some nights when it wasn’t raining went up to 78). Other locations (Chesapeake, Isle of Wight, Prince George/Templeton, Prince George/Disputanta, Warsaw, and Southampton) averaged only about 1 moth per night this week.

Corn earworm black light trap report for July 19, 2018

Corn earworm moth captures in Virginia black light traps ranged from zero to 2 per night this week. Watson Lawrence in Chesapeake averaged 1 moth per night; LIvvy Preisser in Isle of Wight had 0.6 per night; Scott Reiter reported zero in Prince George (Templeton) and 0.5 per night in Disputanta. Mary Beahm in Warsaw saw 0.1 corn earworm moths per night; and in Suffolk we caught an average of 2.1 per night. We look forward to Dwayne Sanders’ help with operating a trap in Waverly!

In 2017, black light trap captures of corn earworm moths started to spike in the third week of July. Please check back for next week’s report!

Corn earworm report for July 12, 2018

Corn earworm moth numbers have been low in local black light traps. Watson Lawrence reported 1.4 per night in Chesapeake; Livvy Preisser averaged 0.6 per night in Isle of Wight; Mary Beahm had zero in Warsaw; we had 0.9 per night in Suffolk this week.

Virginia Cooperative Extension Agents and Virginia Tech employees will be scouting field corn for corn earworm larvae this month as part of Dr. Taylor’s annual survey. They examine ears in five corn fields per county and calculate the average percent infested ears. Corn is a nursery crop for corn earworm–the percent of infested ears can be a useful indicator of the pressure to expect in other crops such as soybean, cotton, peanut, etc. when moths emerge and migrate out of corn. We’ll provide results of the survey in the first week of August.

We have tested 80 corn earworm moths in our cypermethrin vial tests this season, with only 8% surviving the 24-hour exposure to 5 micrograms/vial of cypermethrin. It would be great to see moth survival remain that low, but we need to continue testing to see what happens when we get the flight out of corn and later into the season.