Category Archives: Commodity

Asiatic garden beetle in Virginia cotton–June 12, 2025 update

Asiatic garden beetle (AGB) captures in our Sussex, VA black light trap spiked the first week of June, totaling 1,281 adults over a 7-day span. Some severe AGB foliar injury to seedling cotton was reported near Wakefield (image below). We dug up cotton plants and marestail in AGB hotspots, finding adults under each, but we do not have evidence that they feed on cotton roots. For more information, please see our Virginia Cooperative Extension publication, “Asiatic Garden Beetle in Cotton”

Acephate resistance update in Virginia Cotton

On Monday, May 26 the Tidewater AREC entomology team collected tobacco thrips from cotton throughout southeastern Virginia. These populations were sent to the University of Tennessee where they were tested in the lab for susceptibility to acephate, spinetoram (Hemi SC or Radiant), and dicrotophos (Bidrin). Across all the sites, the results were very consistent with;

75-79% mortality with acephate
100% mortality with spinetoram
47-50% mortality with dicrotophos

We would classify this as tobacco thrips having reduced susceptibility to acephate in southeastern Virginia. Acephate resistance was also previously confirmed in northeastern North Carolina, just across the state line. This year we have found a high proportion of flower thrips, which are harder to kill with acephate, and now have confirmed that acephate has reduced efficacy for tobacco thrips. If you still plan to make a foliar thrips application, or are making a second application after a previous acephate application, Hemi SC (spinetoram) should be considered for more effective control. See this previous blog post for more details on the importance of timing your foliar application for maximum economic return.

We’d like to thank Sebe Brown at the University of Tennesee and his team for running the lab tests and the Virginia Cotton Board for sponsoring this research.

Cotton thrips management

It has been a cool and wet start to the cotton season in southeast Virginia, and growth is slow. With a slow start to the season some folks are considering a second foliar application for thrips management. There are a couple key things to consider…

The first thing to consider for effective thrips management is timing

The most consistent return on investment comes from a foliar application early in the first true leaf stage. An application at the second leaf stage sometimes pays off, which is more likely to be the case with our current growing conditions. If cotton reaches the three or four-leaf stage, foliar applications made for thrips rarely pay off.

The next consideration is what insecticide to chose.

One of the most commonly used products to control thrips with a foliar spray is acephate. There are two thing to consider when using acephate; 1) western flower thrips are not as susceptible to acephate as tobacco thrips, and 2) acephate resistance has been documented in tobacco thrips in northeastern North Carolina, just across the state line from us in southeastern Virginia.

Populations of western flower thrips have been high so far in southeastern Virginia.

In several trials at the Tidewater AREC in Suffolk, we found around 80% western flower thrips in a foliar insecticide trial. Additionally, collections made from grower fields throughout Suffolk and Southampton counties on May 23 averaged 73% western flower thrips. While most fields did have a majority of western flower thrips, it is important to note that it varies between fields even across a relatively small area, and some sampled fields had a larger proportion of tobacco thrips. A table of thrips collections from May 23 can be found below. Each row represents a sample of five cotton plants in a field in Suffolk or Southhampton county.

FieldTobacco thripsWestern flower thrips% Western flower thrips
#12675%
#221386%
#31480%
#442385%
#511321%
#61990%
#71888%
#84450%

In the foliar insecticide test at the TAREC, acephate (at 3 oz/ac) did not provide better control than not treating with these high populations of flower thrips. Hemi SC (spinetoram), provided good thrips control at both the 2.5 and 3 oz rates. Hemi SC is the same active ingredient found in Radiant and is available for use in Virginia and the Carolinas this year for thrips suppression. It is important to mix Hemi SC with a non-ionic surfactant or with an herbicide which already contains a surfactant, to get good thrips control.

If you are using acephate, you should carefully monitor the performance of the application in your field. If you are not satisfied with the performance of an acephate application, the cotton growth stage and the growing conditions at that time should be assessed before considering a second application. If a second application is made, Hemi SC should be considered for more effective control and to rotate the insecticide mode of action. Bidrin should not be used for a second application after acephate, as these two insecticides are the same mode of action.

Both acephate and spinetoram can be washed away by rain up to 8 hours after application (or possibly longer), but acephate is slightly less susceptible to being washed away when comparing the two. However, some protection from a foliar application is better than none under current conditions, which are expected to extend through this weekend.

As a reminder, if you are planting Thryvon cotton, it provides excellent thrips control and does not need a foliar application. If you have any thrips questions contact Tim Bryant (757-621-8804, btim2@vt.edu), field crop entomologist at the TAREC in Suffolk, VA.

Wheat Growth Stages and Scab Management Update – April 25, 2025

Douglas S. Higgins, Assistant Professor and Extension Specialist, Virginia Tech Eastern Shore Agriculture Research and Extension Center

In Virginia, wheat is currently at varying growth stages across the state. Many fields are at the boot stage (Feekes 9) or beginning to head (Feekes 10.1 to 10.3), while in some areas and in early-maturing varieties heads are fully emerged (Feekes 10.5).

For those choosing to make a fungicide application, the optimal timing for managing scab is at early flowering (Feekes 10.5.1) and up to seven days afterward (see figure below). Reminder: Do not use products that contain strobilurins (FRAC 11) to manage scab.  

Warm, humid, and wet conditions leading up to and during flowering favor infection by the scab-pathogen. As of April 25, 2025, conditions in Virginia are not favorable for disease development in flowering wheat. However, for fields expected to flower in the coming days or weeks, monitor your local weather closely and consult the Fusarium Risk Tool (https://www.wheatscab.psu.edu/) for updates on disease-conducive conditions.


Reports of Soybean Aphids

First, I would like to introduce myself. I am Tim Bryant, the new assistant professor of entomology and extension specialist at the Tidewater AREC, in Suffolk, VA. I did my master’s degree here at the TAREC under Dr. Sally Taylor, and I am excited and grateful for the opportunity to come back and work with the farming community in Virginia. I am also looking forward to continuing to provide updates on this platform as regularly as we have updates to provide. Now, on to a quick update from my first few weeks on the job…

Soybean aphids have been reported in Mecklenburg and Prince George counties (First reports 8/28). Aphids can reproduce asexually, and are capable of rapid population growth under the right conditions, so close monitoring is important. Our threshold for managing soybean aphids is 250 per plant at R4 (full pod) or prior, and 1000+ at R5 (beginning seed) and beyond. The below image shows 300 aphids on a single leaflet as a point of reference (Photo credit: Roger Schmidt, University of Wisconsin-Madison, Bugwood.org). There is likely to be multiple developmental stages of aphids present at one time, and early stages are very small.

There are a couple key considerations for managing aphids; 1) they are highly susceptible to population crashes from natural enemies or weather events, and 2) broad-spectrum insecticide applications (i.e. pyrethroids) may kill aphids, but also the afore-mentioned beneficial insects. Eliminating beneficials can potentially flare up spider mites or other pests later on. If you think you may have an aphid problem, scout several areas of the field to estimate the number of aphids per plant and pay close attention to the number of beneficial insects present. Where we scouted for aphids, there were also large numbers of lady beetle adults and larvae, which are excellent aphid predators. If you reach the aphid threshold, sample again in 5-7 days to ensure the population has not crashed. Narrower spectrum insecticides (e.g. sivanto) may preserve some beneficial insects if an application for aphids is made. See our pest management guide (beginning on page “4-62”) for more details on labeled products, application rates, etc.

The below image shows a lady beetle larvae, which were found in abundance along with the aphids we are reporting on here, feeding on an aphid (Photo credit: Winston Beck, Iowa State University, Bugwood.org).

Corn earworm/bollworm update for August 8, 2024

Corn earworm (= bollworm) moth catches were exceptionally high this week, continuing to climb in Dinwiddie, Prince George, and Suffolk, VA black light traps. The average number captured per night was 38 in Greensville, 79 in North Dinwiddie, 72 in Prince George/Disputanta, and 124 in Suffolk. Thanks to Sara Rutherford, Scott Reiter, and the Tidewater AREC entomology crew for their reports. Here is the Table.

Invitation to the Virginia Cotton Growers Association Annual Field Day on August 16, 2024

Location: Virginia Tech Tidewater AREC Research Farm (1045 Hare Road, Suffolk, VA). This event is free and open to the public. Registration begins at 7:30 am with tours starting at 8:00 am. Lunch will be provided, followed by a Peanut Agronomy Tour in the afternoon. Here is the Tour Program.

If you are a person with a disability and desire any assistive devices, services, or other accommodations to participate in this activity, please contact Matthew Chappell, Tidewater AREC Director at (757) 807-6537/TDD 800-828-1120 during business hours of 8:00 a.m. to 4:30 p.m. to discuss accommodations five days prior to the event.

Corn earworm/bollworm update for August 1, 2024

Corn earworm (= bollworm) moth catches increased greatly this week in southeastern Virginia black light traps. The average number captured per night was 50 in Greensville, 42 in North Dinwiddie, 39 in Prince George/Disputanta, and 67 in Suffolk. Thanks to Sara Rutherford, Scott Reiter, and the Tidewater AREC entomology crew for their reports. Here is the Table.

We have evaluated over 250 moths in our 2024 vial tests, with 57% surviving the 24-hour exposure to the pyrethroid insecticide, cypermethrin, at 5 micrograms per vial.

Corn earworm/bollworm moth update–July 25, 2024

Corn earworm (= bollworm) moth catches really started to increase this week in southeastern Virginia black light traps. The average number captured per night this week was 4 in Greensville, 11 in North Dinwiddie/Petersburg, 18 in Prince George/Disputanta, and 30 in Suffolk. Thanks to Sara Rutherford, Scott Reiter, and the Tidewater AREC entomology crew for their reports. Here is the Table

We have evaluated over 150 moths in our 2024 vial tests, with 61% surviving a 24-hour exposure to the pyrethroid insecticide, cypermethrin, at 5 micrograms per vial. Even though cypermethrin is no longer widely used, survival rates this high suggest we need to watch for some pyrethroid control failures, and to consider alternative chemistries when an insecticide is needed.

Asiatic garden beetle update–June 13, 2024

Black light trap catches of AGB per 3 to 4 nights in Sussex County, Virginia were 500 on June 7 and 487 on June 10, 2024. Producers have reported seeing adult AGB just by kicking over the top inch or so of soil in infested areas. I heard of 5 acres of cotton in Suffolk with very heavy AGB defoliation, but there are more reports where injury is not as severe. I look forward to learning when our AGB population will finally decline.