David Ames Herbert, Jr.

Professor

Education

  • Ph.D., Entomology, 1985, Auburn University, Auburn, Ala.
  • M.S., Entomology, 1975, Auburn University, Auburn, Ala.
  • B.S., Biology, 1971, Johnson State College, Johnson, Vt.

Professional Memberships

  • American Peanut Research and Education Society
  • Entomological Society of America
  • Virginia Crop Production Association

Awards

  • Friends of Southern IPM—Lifetime Achievement Award, Southern IPM Center, Blacksburg, Va., 2012
  • Extension Service Award for Outstanding Service to Virginia’s Agribusiness Industry, awarded by the Virginia Agribusiness Council, Warsaw, Va., 2010
  • Andy Swiger Land Grant Award, College of Agriculture and Life Sciences, Virginia Tech, Blacksburg, Va., 2008
  • Extension Award of Merit, Gamma Sigma Delta, VPI&SU Chapter, Blacksburg, Va., 2006.
  • Extension Excellence Award, Virginia Tech Alumni Association, Blacksburg, Va., 2006.
  • Research Award, the Virginia Small Grains Board, 1998.
  • Meritorious Research Award from the Virginia Soybean Association, 1993.
  • Bailey Award, the American Peanut Research and Education Society, Atlanta, Ga., 1990.
  • Outstanding Extension Display Award, Entomological Society of America, Nashville, Tn., 1997.
  • Outstanding Extension Display Award, Entomological Society of America, Louisville, Ky., 1996.
  • Distinguished Achievement Award in Extension Entomology, Eastern Branch of the Entomological Society of America. Harrisburg, Penn., 1995.

Research Statement

Develop (Research, 25 percent) and implement (Extension, 75 percent) programs to improve management of insect pests of soybean, peanut, cotton and small grains that reduce reliance on pesticides while maintaining crop quality and profitability. Produce timely and germane articles for the agricultural press and peer-reviewed publications, and make presentations using a variety of content-based media appropriate for grower, agency, industry and academic audiences. Serve as major advisor and mentor to graduate students. Work collaboratively with grower and industry groups, Extension agents, university and agency personnel. Provide leadership to departmental, college, VCE and university committees and programs. Currently, the State IPM Coordinator and Extension Project Leader for the Department of Entomology. Current projects include biology and management of brown marmorated stink bug (BMSB) in soybean, impact of BMSB to cotton bolls, evaluation of GMO insect-resistant cotton varieties and development of new thresholds for hemipterous pests of cotton, evaluation of peanut cultivars and tobacco thrips management practices for limiting incidence and losses to tomato spotted wilt virus, and research on efficacy of insecticide seed treatments for control of thrips in cotton, peanut, small grain and soybean.

Research Projects

Personnel

Wage or Other Employees

  • Sean Malone, Research Specialist Senior
  • Mike Arrington, Research Specialist
  • Rebecca Arrington, Agricultural Technician

Former Students

  • Katherine Kamminga (2013), Research Assistant, Kentucky State University
  • David Owens (2012), PhD Candidate, University of Florida
  • Jessica Samler (2012), Nichino America, Inc.
  • Mathew Winslow (2011), Tidewater Agronomics, Inc.  
  • Amanda Koppel (2010), E.I. Dupont de Nemours and Company
  • Katherine Kamminga (2008), Postdoctoral Scientist, Virginia Tech
  • David Moore II (2006), VCE Ag and Natural Resources Agent, Mathews, Gloucester, Middlesex Counties
  • Janet L Ashley (2003), VCE Ag and Natural Resources Agent, Isle of Wight County (jaashle2@vt.edu)
  • T. Horner (2002), USDA-APHIS
  • Sean Malone (2001), Research Specialist Senior (smalone@vt.edu)
  • Ginny Barnes (2000), Sales Representative, Pioneer Seeds
  • Robert Ihrig (1998), Corn Technology Specialist, Monsanto Company
  • William J. Petka Jr. (1995), Sales Representative, Monsanto Company

Evaluation of BollgardII, WideStrike and TwinLink cotton varieties for bollworm management and value

PI(s): Herbert, Jr, David Ames

Investigators: Malone, Sean

Abstract: It is important to cotton growers to have access to information on the performance and value of cotton varieties. Cotton is one of the agronomic crops with most of the commercially available varieties being genetically altered to convey protection from Lepidopterous insect pests. There are different genetic events, or insect toxins, available in the many different varieties and the options are changing almost annually. This project is an ongoing effort to evaluate some of the most appropriate varieties for this region for performance (lint yield and quality) and resistance to insects.

Description:

In 2011, 12 standard varieties having either BollgardII or WideStrike insect protection technologies, and three conventional cotton varieties were selected based on previous strong performance in Virginia. Cotton was planted on May 10 using 36-inch row spacing; plots were two rows by 35-ft long with two checker rows of ‘DP 1032 B2RF’ between plots. A split-plot experimental design was used, with each variety either treated with insecticides targeting bollworm, or untreated. In the treated plots, standard varieties received one insecticide spray and conventional varieties received two sprays for bollworm. All plots received the same thrips and stink bug/plant bug management program. Percent bollworm damage was determined by visual in situ examination of 25 bolls per plot on August 8 and 15. Yield was determined by harvesting two rows of each plot (70 row ft) using a commercial two-row cotton picker. Sub-samples were ginned to determine lint versus seed and trash weight.

Project Outcomes:

The three conventional varieties that did not receive insecticides for bollworm management suffered more bollworm injury than untreated standard varieties, with all three exceeding the 3 percent damage threshold. Untreated standard varieties did not exceed this threshold. When conventional varieties received two insecticide applications targeted for bollworm, injury levels were reduced to levels comparable to standard varieties that had received one spray application. The yield increase provided by these bollworm insecticide applications averaged 131 lb lint/acre for the three conventional varieties. However, little was gained this year by treating WideStrike and BollgardII varieties for bollworm, with mean gains of only 9 and 27 lb lint/acre for these standard varieties.

Commodities: Cotton

Resources: Agricultural Experiment Station Facilities, Graduate Assistantship Opportunities, State-Owned Vehicles

Disciplines: Integrated Pest Management

Audiences: Agribusiness, Commodity Groups, Extension Agents, Government Agencies, Producers, Researchers

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Assessment of conventional cotton varieties (non-Bt, non-glyphosate) for fit and value

PI(s): Herbert, Jr, David Ames

Investigators: Malone, Sean

Abstract: Cotton growers in Virginia are paying high seed technology fees for cotton varieties developed of protection against Lepidopterous pests. In many cases, the costs seem to outweigh the benefits, as cotton in Virginia does not typically incur large bollworm infestations. The objectives of this research were to evaluate conventional (non-Bt, non-Roundup Ready) cotton varieties for yield performance, and to weigh costs (including seed, herbicide, and insecticide) versus lint value.

Because of the high seed technology fees, there is interest by Virginia cotton growers to evaluate the fit for conventional cotton varieties. They see these varieties as a possible option for use in ‘marginal’ fields where yield potential is limited. Also, as the number of glyphosate-tolerant weed species is increasing, growers are having to incorporate more ‘traditional’ herbicides into their weed management programs, reducing the value of the Roundup Ready technology. Our data over several years have shown that in general, BG2/RF and WS/Flex varieties must be treated at least one time for bollworm to prevent economic damage. Generally, non-Bt cotton has to be treated only two times. This project documented in six field plot studies the value of conventional vs. standard cotton varieties.

Description:

Three conventional cotton varieties were evaluated in a total of six field trials in 2010 and 2011: SSG HQ 110 CT, SSG HQ 210 CT, and SSG HQ 212 CT (Seed Source Genetics, Bishop, TX). Phytogen 375 WS/RF was used as the standard variety in most comparisons because of its widespread use in Virginia. Split-plot replicated trials were established at the Virginia Tech Tidewater AREC, where main plots received either two threshold-based insecticide applications, or no insecticide for bollworm management. Large-block replicated trials were conducted on three commercial cotton fields, with threshold-based insecticide applications as needed for bollworm management. Insect pressure by bollworm was documented by weekly scouting of plots and insecticides were applied according to recommended thresholds. Boll damage was assessed throughout the season by sampling bollworm populations and boll damage. The overall value of conventional and BG2/WS/RF systems was determined by considering the value of the cotton (lb lint and seed/acre x estimated $/lb) and the costs of bollworm management (insecticide cost, number of applications, and application cost), weed management (herbicide cost, number of applications, application cost), and seed (seed cost with base fungicide only for conventional varieties, and seed cost with the insecticide and RF technology fee for standard varieties).

Project Outcomes:

Overall, conventional varieties yielded well compared with standard varieties. This was evident in the six field trials and from the Official Variety Trials in Virginia. Crop value with conventional varieties ($893-$943/acre) was also comparable to standard varieties ($818-$998). The weed and insect management program products for the conventional varieties cost $34.13 and $4.98, respectively, compared with $6.34 and $1.21 for the standard varieties, and the conventional varieties required an average of 1.16 ($4.02) additional applications (either insecticide or herbicide). However, these additional costs associated with conventional varieties were offset by the lower seed cost. These studies show that growing conventional cotton varieties, although requiring more intensive weed and insect management programs, can be profitable in Virginia. In talking with growers, some see conventional cotton not as a wholesale change but as a fit for 15-20 percent of their acreage—their marginal fields or where there are troublesome weed species that no longer respond to glyphosate applications.

Commodities: Cotton

Resources: Agricultural Experiment Station Facilities, Graduate Assistantship Opportunities, State-Owned Vehicles

Disciplines: Integrated Pest Management

Audiences: Agribusiness, Commodity Groups, Extension Agents, Government Agencies, Producers, Researchers

  • Evaluation of new chemistries for control of bollworm in non-Bt cotton
  • Assessment of new chemistries for management of thrips in cotton and development of improved decision indices

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Comparison of boll feeding injury by native stink bug species and the brown marmorated stink bug

PI(s): Herbert, Jr, David Ames ; Kamminga, Katherine

Investigators: Malone, Sean ; Kuhar, Tom; Toews, Mike (U. Georgia)

Abstract: Stink bugs are a known pest of cotton as they feed directly on developing bolls. New thresholds have been developed to improve management of native stink bug species. The status of the invasive stink bug, the brown marmorated stink bug (BMSB), as it relates to cotton is unknown. Because of its distribution in the mid-Atlantic, Virginia could be the first state where BMSB encounters cotton. Field cage studies have been initiated to assess the damage potential of BMSB to cotton bolls, especially compared to native stink bug pest species.

Description:

Previous research has shown that native green and brown stink bugs are major late-season pests of cotton. Late instar nymphs and adults feed directly on developing cotton bolls causing lint staining, seed death, and boll lock which can all result in yield and lint grade reductions. The recently released “dynamic threshold” suggests action when only 10 percent internal damage occurs for weeks 3-5 of bloom. With the pending threat of the new stink bug pest species, the BMSB, we felt it important to assess its potential impact on cotton. To that end, a series of small and large field cages studies were initiated at the Virginia Tech Tidewater AREC to compare boll damage by BMSB nymphs and adults to that caused by the native green stink bug.

Project Outcomes:

Results from the large cage study in 2011 showed that BMSB adults caused more injury than green stink bug adults to bolls with diameters of 3.8 cm and greater. From the small cage study, we learned that BMSB adults caused significantly more internal warts than green stink bug adults when isolated on 2.8 and 3.2-cm diameter bolls, and green stink bug adults caused more warts and minor stains on 1.8-cm diameter bolls. These findings are important because they suggest that BMSB may have a preference for older bolls — bolls that are considered to be safe from feeding by native species. Cage studies were repeated in 2012 and results are pending. If results are consistent with 2011 findings, it could require changes to existing management thresholds

Commodities: Cotton

Resources: Agricultural Experiment Station Facilities, Graduate Assistantship Opportunities, State-Owned Vehicles

Disciplines: Integrated Pest Management

Audiences: Agribusiness, Commodity Groups, Extension Agents, Government Agencies, Producers, Researchers

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Annual monitoring of pyrethroid susceptibility of corn earworm adults and evaluation of non-pyrethroid alternatives for control

PI(s): Herbert, Jr, David Ames

Investigators: Malone, Sean

Abstract: Corn earworm is the primary insect pest of soybean, cotton, peanut and many other crops in Virginia. Most growers rely on a pyrethroid insecticide for controlling infestations which has lead to concern about the development of resistance/tolerance. A program is in place to document resistance/tolerance levels so growers can be informed about what products may be needed to achieve acceptable levels of control.

Description:

Corn earworm is the primary insect pest of several crops grown in Virginia including soybean (podworm), cotton (bollworm), peanut, and tomato (fruitworm). Over the past 10-15 years, most growers have relied almost exclusively on pyrethroid insecticides for control, often making multiple applications in the same season. A similar habit by growers in the mid-southern US in earlier years lead to build up of resistance/tolerance to this insecticide class resulting in control failures. Since 2003, we have tested approximately 2,500-3,000 bollworm moths for pyrethroid tolerance by subjecting them to the Adult Vial Testing (AVT) program. Glass vials pretreated with 5 micrograms of cypermethrin, and untreated vials, are furnished by a USDA-ARS cooperator. Live moths are collected daily from pheromone traps beginning in May through September. They are placed individually into treated or untreated vials and observed in 24 hours for percent mortality. Weekly summaries of percent survivorship are posted to the Virginia Ag Pest Advisory.

Project Outcome:

Up until 2008, essentially no moths survived the cypermethrin challenge, with an average of less than 5 percent surviving over the entire season. A large and abrupt change occurred on 2008 with almost 20 percent surviving. Since 2008, the percent surviving has gradually increased. In 2012, we tested 3,009 moths from May 31 to September 12 and found a mean seasonal survival rate of 37 percent, the highest seen in Virginia since resistance monitoring began back in 2003, with individual sample date peaks as high as 58 percent survival. Each year we are also documenting field control failures by sampling commercial fields and testing insects after growers had applied a pyrethroid. One case showed the adults reared from the surviving larvae had an AVT survival rate of over 70 percent. Extension educational efforts are resulting in the increased use of non-pyrethroid insecticides by growers and improved control.

Commodities: Soybean

Resources: Agricultural Experiment Station Facilities, Graduate Assistantship Opportunities, State-Owned Vehicles

Disciplines: Integrated Pest Management

Audiences: Agribusiness, Commodity Groups, Extension Agents, Government Agencies, Producers, Researchers

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Effects of temperature and relative humidity on the vertical distribution of stink bugs (Hemiptera: Pentatomidae) within a soybean canopy and implications for field sampling

PI(s): David Owens, Herbert, Jr, David Ames

Investigators: Kuhar, Tom; Reisig, Dominic (NCSU)

Abstract: Stink bug (Hemiptera: Pentatomidae) vertical position in a soybean canopy could influence sweep net sampling efficiency. This study examined the effects of both ambient and within-soybean canopy temperature and relative humidity on stink bug vertical distribution in two commercial soybean fields with full canopies in Virginia.

Description:

A field study was conducted to determine the effects of both ambient and within-soybean canopy temperature and relative humidity on stink bug vertical distribution in a soybean canopy. In 2010 and 2011, temperature and relative humidity were continuously monitored in the upper and lower plant canopy. The within-canopy vertical distribution of a minimum of 20 stink bugs was documented at each of four different observation times: observations were replicated on different days 14 times in the morning between 7 and 8:30 a.m. EST, 14 around noon, 15 during the mid-afternoon between 3 and 4:45 p.m., and five observations were replicated in the early evening after 6:15 p.m.

Program Outcomes:

Acrosternum hilare Say was the primary species observed with 88 percent of the total in 2010 and 59 percent in 2011; the remainder was primarily Euschistus servus Say. No significant relationship was observed between the environmental parameters measured or time of day on the stink bug vertical distribution in the canopy. Regardless of environmental conditions, an average of 15-20 percent of stink bugs was located below the normal 38 cm sweep net sampling zone. Results showed that in Virginia soybean fields, sweep net sampling efficiency for stink bugs does not appear to be significantly affected by changes in temperature, relative humidity, or time of day, and sweep netting the upper canopy accesses 80 percent of the total population. This project, as part of the thesis research for M.S. student, David Owens, was accepted for publication in the Journal of Entomological Science.

Commodities: Soybean

Resources: Agricultural Experiment Station Facilities, Graduate Assistantship Opportunities, State-Owned Vehicles

Disciplines: Integrated Pest Management

Audiences: Agribusiness, Commodity Groups, Extension Agents, Government Agencies, Producers, Researchers

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Evaluation of soybean seed and pod injury caused by Halyomorpha halys

PI(s): David Owens, Herbert, Jr, David Ames

Investigators: Kuhar, Tom; Dively, Galen (U Maryland); Reisig, Dominic (NCSU)

Abstract: The brown marmorated stink bug, Halyomorpha halys Stål (Hemiptera: Pentatomidae) is a recently introduced phytophagous stink bug pest in Mid-Atlantic soybean. Currently, there is little information indicating how this new pest should be managed in soybean or if economic thresholds should be adjusted. Field cage studies were conducted in Beltsville, MD and Suffolk, VA to evaluate H. halys injury to several different soybean reproductive development stages.

Description:

In 2010 and 2011, field cage studies were conducted in Beltsville, MD and Suffolk, VA to evaluate H. halys injury to several different soybean reproductive development stages during a two-week infestation period using densities of densities of zero, one, two, four, and eight fifth instar and adults per 0.3 row m. Cage plots were harvested, and subsamples were taken to determine pod losses and seed quality.

Program Outcomes:

Results showed that feeding injury to soybean caused by H. halys was similar to native stink bugs, with seed destruction, punctures, destroyed pods, and yield loss being observed. Threshold densities of one stink bug per 0.3 row m were low enough to cause significant seed damage, and consistent damage resulted from densities of four bugs per 0.3 row m. The full flowering R2 soybean development stage was least affected by H. halys feeding, while the full pod R4 stage was the most sensitive, and slightly more sensitive than the full seed R6 stage. While no yield loss was associated with stink bug densities, significant seed injury to R4 caged soybean was noted at even low densities. This project, as part of the thesis research for M.S. student, David Owens, was submitted to the Journal of Economic Entomology and is currently in the review process.

Commodities: Soybean

Resources: Agricultural Experiment Station Facilities, Graduate Assistantship Opportunities, State-Owned Vehicles

Disciplines: Integrated Pest Management

Audiences: Agribusiness, Commodity Groups, Extension Agents, Government Agencies, Producers, Researchers

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Impact of neonicotinoid seed treatments on thrips (Thysanoptera: Thripidae) and soybean yield in Virginia and North Carolina

PI(s): Reisig, Dominic (NCSU); Herbert, Jr, David Ames

Investigators: Malone, Sean

Abstract: Currently there are several neonicotinoid insecticide seed treatments registered for use on soybean (Glycine max L.), with disparity in adoption rates in the eastern United States. A complex of seedling insect pests is found in mid-south soybean, but thrips are the primary early season pest of soybean in Virginia and North Carolina. Published knowledge regarding their impact on soybean yield is minimal. Field experiments were conducted to evaluate the impact on thrips population dynamics and the influence on yield.

Description:

Currently there are several neonicotinoid insecticide seed treatments registered for use on soybean (Glycine max L.), with disparity in adoption rates in the eastern United States. A complex of seedling insect pests is found in mid-south soybean, but thrips are the primary early season pest of soybean in Virginia and North Carolina. Published knowledge regarding their impact on soybean yield is minimal, as is the impact of thrips on soybean yield; thrips species composition is also understudied. In 2008 through 2010, nine field experiments in Virginia and North Carolina were conducted to evaluate the impact on thrips population dynamics; the influence on yield of neonicotinoid seed treatments, imidacloprid and thiamethoxam, was reported from nine of these experiments. Moreover, thrips species abundance was recorded in three of these experiments.

Program Outcomes:

Both imidacloprid and thiamethoxam reduced thrips densities compared with untreated soybean. Thiamethoxam was more effective than imidacloprid in reducing adult thrips densities at 5 wk after planting. Adult densities peaked at three weeks after planting, followed by larval densities, which peaked at four weeks after planting. The most abundant thrips species was Frankliniella fusca (Hinds), followed by Neohydatothrips variabilis (Beach). Other common species included F. occidentalis (Pergande) and F. tritici (Fitch). In general, F. fusca was more common earlier in the season, while N. variabilis was more common later in the season. There were no significant differences in yield among any of the treatments or in the untreated controls. Although neonicotinoid insecticides reduced thrips abundance, data collected in these studies demonstrated that there was no positive yield response. Project results were published in the Journal of Economic Entomology, 105(3): 884-889; DOI: http://dx.doi.org/10.1603/EC11429.

Commodities: Soybean

Resources: Agricultural Experiment Station Facilities, Graduate Assistantship Opportunities, State-Owned Vehicles

Disciplines: Integrated Pest Management

Audiences: Agribusiness, Commodity Groups, Extension Agents, Government Agencies, Producers, Researchers

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Within plant distribution and species complex of thrips (Thysanoptera: Thripidae) on soybean seedlings in Virginia

PI(s): Samler, Jessica; Herbert, Jr, David Ames

Investigators: Malone, Sean; Owens, David; Kuhar, Tom; Brewster, Carlyle

Abstract: Several thrips species are known to feed on soybean and can cause yield reductions if injury to seedlings is exacerbated by other environmental factors. There is little information available about where thrips are located on soybean seedlings or how best to sample plants to estimate population densities. A study was conducted in seedling soybean to evaluate the within-plant location of thrips, whether populations from specific plant parts (subsamples) can be used to accurately estimate whole plant populations, and to determine the thrips species complex present as well as the evenness of the sampled population.

Description:

A two-year study was conducted in seedling soybean to evaluate the within-plant location of thrips, whether populations from specific plant parts (subsamples) can be used to accurately estimate whole plant populations, and to determine the thrips species complex present as well as the evenness of the sampled population. In each of two years, four soybean seedlings were randomly selected from eight locations per field. The seedlings were sectioned into three parts. Thrips larvae and adults were counted on the Terminal, the Trifoliate,and the Remainder of each plant; in addition, the leaf area of the plant material was determined.

Program Outcomes:

The most abundant species of thrips found were soybean thrips, Neohydatothrips variabilis (Beach). Evenness of the population was 0.71 and 0.51 (2010 and 2011, respectively). Larval density was highest in the Terminal section, while the highest total numbers occurred on the Remainder of the plant. There was no significant relationship between leaf area and number of larvae in any plant section. The number of larvae on the Remainder of the plant had the strongest relationship to whole plant counts (R2 = 0.88) followed by the Trifoliate section (R2 = 0.54). There was no significant relationship between counts of thrips from the Terminal section and the whole plant counts (R2 = 0.06). This project, as part of the Thesis research for M.S student, Jessica Samler, was published as an abstract in Virginia Journal of Science 62 (1 & 2): 17.

Commodities: Soybean

Resources: Agricultural Experiment Station Facilities, Graduate Assistantship Opportunities, State-Owned Vehicles

Disciplines: Integrated Pest Management

Audiences: Agribusiness, Commodity Groups, Extension Agents, Government Agencies, Producers, Researchers

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Field efficacy and acute toxicity of cyantraniliprole, a novel diamide insecticide, against thrips (Thysanoptera: Thripidae) on cotton and peanut seedlings

PI(s): Samler, Jessica; Herbert, Jr, David Ames

Investigators: Malone, Sean; Owens, David

Abstract: Tobacco thrips, Frankliniella fusca, attack cotton and peanut seedlings early in the growing season throughout most of the eastern United States and can cause significant yield losses if not controlled. Growers of these crops rely primarily on various seed, in-furrow or post-emergence foliar applied insecticide treatments to manage thrips infestations. Because of insecticide resistance development and the changing availability of commercial insecticide products, it is important to evaluate new insecticides for efficacy. Field experiments were conducted to assess the efficacy of cyantraniliprole, a novel diamide insecticide.

Description:

Field experiments were conducted to assess the efficacy of cyantraniliprole applied to cotton and peanut as a liquid in-furrow or broadcast spray application against naturally occurring thrips infestations. Thirps populations, thrips-induced plant injury and crop yield were evaluated.

Program Outcomes:

In both crops cyantraniliprole significantly reduced the number of immature thrips and the amount of thrips feeding injury to the plants. In several instances cotton lint and peanut pod yields were higher than those obtained in the non-treated controls, and statistically similar to yields obtained with the standard thrips control insecticides of aldicarb 15G, acephate 97, and phorate 20G. These results indicate that cyantraniliprole is a promising new insecticide with a different mode of action and non-target toxicity profile that could be incorporated into thrips management programs in cotton and peanut crops. Peanut leaf-dip bioassays were also conducted to determine the acute toxicity of cyantraniliprole to laboratory-reared adult tobacco thrips. The lethal concentration for fifty percent of the tested population was found to be 166.9 ppm which is considerably lower than the tested field rate of 738.1 ppm. This project, as part of the Thesis research for M.S student, Jessica Samler, was submitted to Crop Protection and is currently under review.

Commodities: Cotton, Peanut

Resources: Agricultural Experiment Station Facilities, Graduate Assistantship Opportunities, State-Owned Vehicles

Disciplines: Integrated Pest Management

Audiences: Agribusiness, Commodity Groups, Extension Agents, Government Agencies, Producers, Researchers

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Evaluation of thrips abundance and injury to plants and incidence of tomato spotted wilt virus in Virginia market-type peanut lines

PI(s): Philips, Chris; Herbert, Jr, David Ames

Investigators: Balota, Maria; Malone, Sean

Abstract: Virginia peanut growers need additional avenues to improve profitability. Better understanding the susceptibility levels of advanced breeding lines and commercially available varieties to thrips could reduce management costs through appropriate variety selection. This project was conducted to evaluate selected line and varieties to susceptibility to thrips and pod yield response.

Description:

All experiments were conducted at the Virginia Tech Tidewater AREC, Suffolk, VA. Peanut variety and line selection was based on performance in previous Peanut Variety and Quality Evaluation trials. In 2010 two peanut varieties and three lines were tested, and in 2011 two peanut varieties and three lines were tested. All varieties/lines received a fungicide seed treatment and plant beds were fumigated prior to planting with Vapam @ 10 gal/acre for control of soilborne plant diseases. Peanuts were planted at the end of April or in early May, in plots 2 rows by 30 or 40 ft long on 36-in beds in a randomized complete block or split-plot experimental design. Plots received either no insecticides applied for thrips control, or conventional thrips control insecticides. Data included weekly thrips plant injury ratings (on a scale of 0 = no injury to 10 = dead plants), terminal leaflet thrips counts (based on 10 leaflets/plot with thrips extraction in soapy water), seedling stand counts, incidence of tomato spotted wilt virus (TSWV) (number of plants showing visual disease symptoms) and pod yield. Data were analyzed using ANOVA and LSD statistical procedures. Plant injury rating and thrips counts were analyzed by variety/line and separated by date, year and insecticide treatment. Yield data were analyzed by variety/line separated by year and insecticide, and TSWV was analyzed by variety/line and insecticide.

Project Outcomes:

In untreated plots, significant differences were observed in thrips feeding induced plant injury rating on some varieties/lines for specific dates in 2010 and 2011 but overall there was no significant difference. In treated plots significant differences were detected by variety/line for specific dates in 2011 and but not in 2010. Significant differences were detected for thrips counts in untreated plots on two dates in 2010 with no significant differences in 2011, or by year. Varietal/line yields were not significantly different in 2010, but were significantly different in treated and untreated plots in 2011. Significant differences in incidences of TSWV were observed in variety/line on both dates in untreated plots and only on 5-Aug in treated plots.

This project supported by the Virginia Peanut Board and National Peanut Board, built upon previous research at the Tidewater AREC concerning susceptibility of commercially available varieties and advanced peanut breeding lines to thrips. While significant differences were detected on some dates in regards to thrips injury to plants, the percentage of leaves injured in insecticide untreated plots would be considered unacceptable by growers. Therefore, we conclude that in both years, no meaningful differences in susceptibility to thrips injury were detected. In these and previous field research experiments, no peanut breeding lines or varieties have exhibited a consistent difference in numbers of thrips present, or the level of plant injury. These results indicate that to date, all varieties and lines appear to be equally attractive to thrips as they invade and populate fields, and are equally susceptible to injury. There have been differences in incidence of tomato spotted wilt among cultivars, but these differences have been erratic and unpredictable.

Commodities: Peanut

Resources: Agricultural Experiment Station Facilities, Graduate Assistantship Opportunities, State-Owned Vehicles

Disciplines: Integrated Pest Management

Audiences: Agribusiness, Commodity Groups, Extension Agents, Government Agencies, Producers, Researchers

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Using degree-days to predict cereal leaf beetle (Coleoptera: Chrysomelidae) egg and larval population peaks

PI(s): Philips, Chris; Herbert, Jr, David Ames

Investigators: Malone, Sean ; Kuhar, Tom; Reisig, Dominic (NCSU)

Abstract: To improve cereal leaf beetle scouting efficiency and encourage the use of thresholds, temperature-based degree-day models were developed and tested to determine their accuracy to predict the date of egg and larval peaks. Previously published cereal leaf beetle temperature development data were used to create the degree-day model. This model of 182 degree-days using a base development temperature of 8ºC was validated using cereal leaf beetle sampling data from four locations in Virginia and North Carolina in 2010, and six locations in 2011. In both years, the degree-day model predicted the average egg peak within 3 d of the observed calendar date. There was also a consistent period between egg and larval peaks averaging 17.5 d. Given the accuracy of this model, historical high and low temperature data were used to create a predictive map of the calendar week that different areas of Virginia and North Carolina would exceed 182 degree-days, and was validated using survey data from 60 field sites in 2010 and 65 sites in 2011 throughout Virginia and North Carolina. Finally, correlation and linear regression analyses were performed using data from all cereal leaf beetle study populations in 2010 and 2011, as well as previously collected data to determine if the number of eggs at peak could be used to predict larval peak numbers. There was a significant positive linear relationship between egg peak density and larval peak density explaining 94 percent of the variation seen in larval peaks, indicating that egg peaks could reliably predict larval infestation levels.

Description:

Population Peaks and Degree-Days. Cereal leaf beetle temperature development data from previously published studies were used to create a predictive degree-day model to estimate the dates of peak egg and larval populations. This model was validated using cereal leaf beetle population data from four wheat fields in Virginia and North Carolina in 2010, and six fields in 2011. In 2010, cereal leaf beetle populations were monitored weekly from the first adult appearance through egg deposition and larval development until emergence of second-generation adults, and in 2011, all populations were monitored twice weekly and all other methods remained the same.

Predictive Map. Using a lower development threshold of 8°C a predictive map for Virginia and North Carolina was created using BioSIM 10, a seasonal pest biology forecasting system and ArcGIS. Thirty-year normal temperature data (1981-2010) from over 489 weather stations in Virginia and neighboring states were used to generate a map of the calendar day of 182 degree-day threshold at a resolution of 1km x 1km cells. This map was validated using survey data from 60 field sites in 2010 and 65 sites in 2011 throughout Virginia and North Carolina.

Eggs to Predict Larvae. To determine if the number of cereal leaf beetle eggs present at peak could be used to accurately predict the likelihood of a field exceeding threshold, the relationship between peak egg numbers and peak larval numbers was examined using correlation and linear regression.

Project Outcomes:

Population Peaks and Degree-Days. Over the two years of the study, the model of 182 degree-days with a lower development threshold of 8°C predicted observed average egg peak within 3 days with a range of 0 to 16 d and average larval peak occurring 17.5 days later with a range of 7 to 35 days.

Validating Predictive Map. In 2010, the map was accurate at all sites within 11 d, with an average difference between predicted and observed of 3 days. The map accurately predicted 88 percent of fields within one week and predicted 98 percent of fields within 10 days. In 2011, variation in prediction ranged from 0 to 11 days with an average difference of 4 days. The map accurately predicted 77 percent of the fields within 7 days and 98 percent of the fields within 10 days. Over the two years of the study, the map predicted all sites within 11 days with 81 percent of fields predicted within 7 days and 98 percent within 10 days. The difference between predicted and observed for all populations was 4 days, with only two sites outside of 10 days.

Eggs Density Predicting Larval Density. A significant correlation was detected between egg and larval peaks for all populations in 2010 and 2011 (F = 135.13; df = 1,8; P < 0.0001) as well as for previously collected data (F = 147.09; df = 1,13; P < 0.0001). Using data from all study populations in 2010 and 2011 this correlation and linear regression model indicates a strong significant positive correlation (r = 0.97) between egg and larval peaks explaining 94 percent of the variation seen in larval peaks (R2 = 0.94; P < 0.0001). This trend held true when the same analysis was performed on data collected in a previous study (r = 0.96; R2= 0.92; P0.0001).

In summary, our data show that a model based on temperature can accurately predict the date of cereal leaf beetle egg peak in Virginia and North Carolina, and that peak larval densities occur approximately 17.5 d after egg peak. Our data also indicate that cereal leaf beetle egg density can be used as a predictor of larval peak density, and concomitant likelihood of a field exceeding the economic threshold. These data can improve the efficiency of cereal leaf beetle management by predicting a calendar date to begin scouting, narrowing this window from several weeks to a few days. This eliminates the need for long-term, labor-intensive scouting programs and reduces the scouting to one or two days.

Commodities: Small Grains

Resources: Agricultural Experiment Station Facilities, Graduate Assistantship Opportunities, State-Owned Vehicles

Disciplines: Integrated Pest Management

Audiences: Agribusiness, Commodity Groups, Extension Agents, Government Agencies, Producers, Researchers

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Extension Statement

New practices, research finds and pest management recommendations are extended to clientele through a variety of media and methods.  In-season field tours, on-farm trials and demonstrations, and research plot focus groups are used to provide visual and hands-on exposure to new pest management practices. 

Publications, news articles and weekly e-mail pest advisories are delivered via the Virginia Ag Pest Advisory.  Insect pest and insecticide control recommendations are provided via several annually updated crop production guides. Selected Extension publications are included at the bottom of the ‘Publications’ list provided.

 

Extension Projects

 

Cotton Insect Pest Management

PI(s): Herbert, Jr, David Ames

Investigators: Malone, Sean

Abstract: Cotton acreage increased in Virginia in the early 1990s to between 85,000 to 120,000 acres grown annually and it remains a viable alternative for growers in the southeastern region of the state. In Virginia, cotton is in its northernmost location in the US and therefore experiences a unique combination of insect pest problems. Each year, numerous field experiments are conducted at the Tidewater AREC to evaluate common pests (primarily thrips, cotton bollworm, and stink bugs) and to develop management programs. Among the many objectives are evaluating compensation ability and yield impact after pest damage, determining the most efficient timings and application systems for standard pesticides, evaluating GMO insect-resistant varieties and new alternative pesticides, and developing and improving control decision guidelines.

Description:

There are currently between 85,000 and 120,000 acres of cotton grown in Virginia with a cash receipt value of almost $39 million. Growers are challenged by a variety of insect pests that threaten lint yield and quality. Because of its northern latitude, Virginia has fewer available heat units relative to other cotton-producing states and there may be limited opportunity for compensation from loss of developing bolls to insect feeding. Tobacco thrips, a complex of hemipterans such as green stink bug, and a bollworm complex including cotton bollworm and tobacco budworm are the major pests. This program addresses development and implementation of pest management programs to minimize losses to these pests using the most economic and environment/user friendly practices available. Each year, many field research experiments are conducted to evaluate new insecticides and GMO insect-resistant varieties for managing these pests. Research is also underway to develop new scouting practices and economic thresholds. A 3-year study evaluating the impact of removing different numbers of insect-susceptible bolls showed that cotton could compensate from boll loss as high as 20% which allowed the threshold to be increased. These studies, as well as county on-farm replicated strip trials with cooperating growers, are used for in-season educational programs where agents, growers and Ag-industry view plots and receive training in sampling and determining treatment thresholds. A regional (VA, NC, SC, GA, AL) project was recently completed to develop new management procedures for hemipterous pests of cotton. New sampling and threshold recommendations for stink bug pests were recently released in two publications, Managing Stink Bugs in Cotton: Research in the Southeast Region (VCE Publ. 444-390), and Scouting for Stink Bug Damage in Southeast Cotton: Description and Use of a Pocket Scouting Decision Aid (VCE Publ. 3005-1445). Annually updated insect pest management recommendations are also provided in the Virginia Cotton Production Guide (AREC-8) and Pest Management Guide for Field Crops--Cotton Insects (VCE Publ. 456-016). In season data summaries and pest advisories are delivered via the Virginia Ag Pest Advisory.

Program outcomes:

In recent years, many Virginia cotton growers have adopted recommended management practices that include use of field scouting and economic thresholds. For example, currently only an estimated 56% of the total cotton acreage is treated for mid-season pests, compared with almost 90% in North Carolina, our closest comparison point. Growers make an average of 2.8 insecticide applications per acre, at a total cost of $45.40 per acre (product + application cost) which is one of the lowest cost insect control programs of all southeastern states. This is in part due to differences in pest species and abundance, but is also due to the success of this program in instilling an IPM, spray-conservative mentality in Virginia cotton growers.

Commodities: Cotton

Resources: Agricultural Experiment Station Facilities, Graduate Assistantship Opportunities, State-Owned Vehicles

Disciplines: Integrated Pest Management

Audiences: Agribusiness, Commodity Groups, Extension Agents, Government Agencies, Producers, Researchers

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Peanut Insect Pest Management

PI(s): Herbert, Jr, David Ames

Investigators: Malone, Sean

Abstract: Peanut is an important commodity in southeast Virginia supplying both in-shell and gourmet kernel markets. A variety of insect pests have the potential to reduce kernel quality and gross pod yields. One of the most challenging is southern corn rootworm, a soil pest that feeds on developing pods reducing yield and allowing entry of secondary rotting organisms. An IPM program has been developed that uses a risk index to aid growers in rootworm management. Work is also in place to develop improved systems for reducing direct damage by thrips and incidence of the thrips-transmitted tomato spotted wilt virus.

Description:

There are currently about 20,000 acres of peanut grown in Virginia, primarily in the southeastern-most 8-county area of the state.  Southern corn rootworm is a sporadic soil insect pest of peanuts that is hard to detect and sample.  We have developed a simple-to-use advisory that uses soil and cultural characteristics to identify those fields not at risk for pod damage or economic loss.  Growers can access the Peanut Southern Corn Rootworm Advisory (VCE Publ. 444-351), input responses that characterize field risk and determine which fields need to be treated with insecticide.  Tomato spotted wilt virus which is transmitted by thrips, is plant disease that is reducing peanut yields.  Field projects led to the development of new thrips control strategies that significantly reduce virus incidence.  An index was developed that integrates planting date, variety selection, seed rate, and thrips control insecticide (Managing Tomato Spotted Wilt Virus in Peanuts in North Carolina and Virginia, NC Coop. Ext. Publ. AG-638).  Annually updated peanut pest management information can be located in the Integrated Pest Management Peanut Scouting Manual (VCE Publ. 444-126) and the Peanut Production Guide (VCE Publ. PPWS-3)

Program outcomes:

The Southern Corn Rootworm Advisory can save time and money as well as help growers use insecticides more efficiently.  Adoption of the advisory has lead to an overall reduction in soil insecticide use from an estimated 90 percent of the total acreage, to less than 50 percent currently. Growers are adopting the TSWV index practices and minimizing disease incidence and losses.

Commodities: Peanut

Resources: Agricultural Experiment Station Facilities, Graduate Assistantship Opportunities, State-Owned Vehicles

Disciplines: Integrated Pest Management

Audiences: Agribusiness, Commodity Groups, Extension Agents, Government Agencies, Producers, Researchers

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Soybean Pest Management Program

PI(s): Herbert, Jr, David Ames

Investigators: Malone, Sean

Abstract: Soybean is one of the most important row crops in Virginia with 500,000 to 600,000 acres planted annually. The primary insect pest is the corn earworm that feeds directly on pods. A large-scale IPM program is in place to promote good management practices that includes annual monitoring, weekly pest advisories and a web-based economic threshold calculator. New projects are in place to monitor and develop management programs for invasive species including and the brown marmorated stink bug (BMSB) and kudzu bug.

Description:

There are currently 500,000 to 600,000 acres of soybean grown in 58 counties in Virginia, primarily in the eastern half of the state, with a cash receipt value of almost $117 million.  Corn earworm (CEW) is the primary insect pest as larvae feed directly on developing soybean seed causing yield reductions.  Each year CEW invades the soybean crop causing growers to apply insecticide treatments to many fields.  However, the size of the pest population and area infested varies from year to year and growers are encouraged to scout fields to determine which need protection.  The Virginia Corn Earworm Advisory was initiated in the early 1990s to provide the IPM practices and the tools for dissemination.  A five year research program established economic thresholds that have been updated as cultural practices have changed.  An electronic Corn Earworm Calculator is available that instantly calculates the threshold for each entry based on the row spacing, the sampling device used, the estimated cost of application, and the estimated crop value ($/bushel).  The Advisory combines annual field surveys and pest monitoring to provide growers with up-to-date information on CEW abundance and movement.  Each year about 7,500 ears of field corn are sampled from 140 fields in 29 counties to determine the size of the earworm population and to make predictions about the upcoming threat to the soybean crop.  A series of 19 black light traps, operated by VCE ANR Agents and volunteers, is used to monitor moth movement into the soybean crop.  Weekly electronic advisories posted to the Virginia Ag Pest Advisory keep growers abreast of pest development and encourage use of scouting and other IPM practices.  Soybean aphid, an invasive pest from Asia, was discovered in the north-central region of the US in 2000.  By 2001, aphids were detected in many soybean growing counties of Virginia, but only at very low, non-economic levels. A 12-miniute web-based multi-media breeze presentation was developed for training clients how to use a new aphid speed scouting procedure. Due to the impending threat by BMSB, a statewide soybean field surveillance program was initiated in 2009. 

Program outcomes:

As a result of the CEW management program, almost 60 percent of the soybean crop (almost 200,000 acres) is scouted annually by growers and crop advisors.  Acreage treated varies each year with the intensity of the infestation, but seldom exceeds what is needed to control the pest.  BMSB were first found in soybean fields in 2010 in 15 counties in the north central region. In 2011, they spread to 20 counties, and by 2012 they spread to soybean fields in 44 counties, over half of the major soybean growing counties, ranging from the northernmost to the Carolina border. Many growers treated fields/field edges. For the first time, in 2012 they were found in soybean fields 3 counties in the coastal plain region.  The first kudzu bug, a nymph, was found in 2011 in kudzu in one county.  By 2012, adults were found in soybean fields in19 counties, and nymphs in 3 counties.  And for the first time, in 2012 BMSB and kudzu bugs were found in the same soybean fields in 10 counties.

Commodities: Soybeans

Resources: Agricultural Experiment Station Facilities, Graduate Assistantship Opportunities, State-Owned Vehicles

Disciplines: Integrated Pest Management

Audiences: Agribusiness, Commodity Groups, Extension Agents, Producers, Researchers

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Virginia Ag Pest Advisory

PI(s): Herbert, Jr, David Ames

Investigators: Malone, Sean

Abstract: An electronic newsletter, the Virginia Ag Pest Advisory was created to improve dissemination of IPM information. In the past, clientele could receive a jumble of information regarding pest management, often from several different sources. We launched the Virginia Ag Pest Advisory in cooperation with the Southern Region IPM Center in Raleigh, NC. The advisory is a database-driven website that compiles pest updates from multiple IPM specialists. Specialists enter their update(s) at a time that is convenient and each entry is categorized by commodity and pest group and identified by a brief title. The compiled advisory in a newsletter format is automatically emailed once a week to the recipient list (currently over 350 individuals). Individual entries can be viewed, or the entire newsletter. The advantage of this system to the recipient is that it is a single-source provider of updated pest information, everything is in one location and users become accustomed to having it delivered at the same time each week.

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Insect Pest ID Guides

PI(s): Herbert, Jr, David Ames

Investigators: Malone, Sean ; Kamminga, Katherine; Kuhar, Tom; Youngman, Rod; Greene, Jeremy (Clemson U.); Dively, Galen, Dively (U. Maryland; Whalen, Joanne (U. Delaware); Tooker, John (Penn State U.

Abstract: Two insect pest ID guides are available by contacting me at herbert@vt.edu or pdf versions can be viewed on the Virginia Cooperative Extension website. The Mid-Atlantic Guide to the Insect Pests and Beneficials of Corn, Soybean and Small Grains was released in 2005.  Accurate identification of insect pest and beneficial species is essential to practicing IPM. However, proper identification of insect pests continues to challenge growers and agriservice personnel involved in pest management in field crops.  Publication of the first version was funded by grants from two agencies — USDA-CSREES-SRIPM and VDACS.  It is a simple, pocket sized, coil bound, laminated guide with clear, high-resolution full-color photos of 40 insect pests and 10 beneficial insects of corn, soybean, and small grains. Insects are grouped by commodity, along with keys for easy separation of the most commonly misidentified species. Ten thousand copies were produced and were distributed across the mid-Atlantic region.  To include new insect pest species that invaded the mid-Atlantic region since the release of the first edition, an updated second addition was printed in 2011 (VCE Publ. 444-360).  Funding was provided by the United Soybean Board and 10K copies were distributed across the eastern states.  Another guide, Field Guide to Stink Bugs of Agricultural Importance in the Upper Southern Region and Mid-Atlantic States (VCE Publ. 444-356), is similarly designed and contains full-color photos of 26 stink bug species of this region including (some species) egg, nymph and adult stages, and photos of typical damage symptoms to fruit and row crops. To date, 13,600 copies have been requested and distributed to individuals/extension agents/industry/other agencies in 29 US states and Canadian Provinces.

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Papers in Refereed Journals (*denotes student or postdoctoral scientist)

  • Owens, D.R.*, D.A. HERBERT, Jr., G. Dively, D.D. Reisig, T.P. Kuhar.  2013. Does feeding by Halyomorpha halys Stål (Hemiptera: Pentatomidae) reduce soybean seed quality and yield?  J. Econ. Entomol. 106: 1317-1323, ISSN 0022-0493, Online ISSN: 1938-291X

  • Owens, D.R.*, D.A. HERBERT, Jr., T.P. Kuhar, and D.D. Reisig.  2013. Effects of temperature and relative humidity on the vertical distribution of stink bugs (Hemiptera: Pentatomidae) within soybean canopies and implications for field sampling. J. Entomol. Sci. 48(2): 90-98.
  • Reisig, D.R., J.S. Bacheler, D.A. Herbert, T. Kuhar, S. Malone, C. Philips, and R. Weisz. 2012. Efficacy and value of prophylactic vs. integrated pest management approaches for management of cereal leaf beetle (Coleoptera: Chrysomelidae) in wheat and ramifications for adoption by growers. J. Econ. Entomol. 105(5): 1612Ð1619 (2012); DOI: http://dx.doi.org/10.1603/EC12124
  • Owens, D.R.*, D.A. HERBERT, Jr., T.P. Kuhar, and D.D. Reisig.  2012. Effects of temperature and relative humidity on the vertical distribution of stink bugs (Hemiptera: Pentatomidae) within soybean canopies and implications for field sampling. J. Entomol. Sci. (accepted, Aug. 30, 2012).
  • Kamminga, K.L.*, A.L. Koppel*, D.A. HERBERT, Jr., and T.P. Kuhar.  2012. Biology and management of the green stink bug.  J. IPM.  3(3): C1-C8(8).
  • Reisig, D.D., D.A. HERBERT, and S. Malone.  2012. Impact of neonicotinoid seed treatments on thrips (Thysanoptera: Thripidae) and soybean yield in Virginia and North Carolina.  J. Econ. Entomol. 105(3): 884-889; DOI: http://dx.doi.org/10.1603/EC11429.
  • Philips, C.R.*, D.A. HERBERT, T.P. Kuhar, D.D. Reisig, and E.A. Roberts.  2012. Using degree days to predict cereal leaf beetle (Coleoptera: Chrysomelidae) egg and larval population peaks. Environ. Entomol. 41(4): 761-767.
  • Samler, J.A.*, D.A. HERBERT, S. Malone, D. Owens*, T.P. Kuhar, and C. Brewster.  2012. Location of thrips (Thysanoptera: Thripidae) on soybean seedlings and implications for sampling. Virginia J. of Sci. 62 (1 & 2): 17 (abstract).
  • Cook, D., D.A. HERBERT, Jr., S.D. Akin, and J. Reed.  2011. Biology, crop injury, and management of thrips (Thysanoptera: Thripidae) infesting cotton seedlings in the United States. 2(2):  http://dx.doi.org/10.1603/IPM10024.
  • Philips, C.R.*, D.A. HERBERT, T.P. Kuhar, D.D. Reisig, W.E. Thomason, and S. Malone.  2011. Fifty years of cereal leaf beetle in the U.S.: an update on its biology, management, and current research.  J. Integ. Pest Mngmt. 2(2): 2011; DOI: http://dx.doi.org/10.1603/IPM11014
  • Koppel, A.L.*, D.A. HERBERT, Jr., T. P. Kuhar, S. Malone, and M. Arrington.  2011. Efficacy of selected insecticides against eggs of Euschistus servus and Acrosternum hilare (Hemiptera: Pentatomidae) and the egg parasitoid Telenomus podisi Ashmead (Hymenoptera: Scelionidae).  J. Econ. Entomol. 104: 137-142.
  • Koppel, A.L.*, D.A. HERBERT, Jr., and E.W. Westbrook.  2010.  Using microscopy to assess chorion structural integrity and parasitoid oviposition sites on stink bug (Hemiptera: Pentatomidae) eggs.  Microsc. and Microanal. Page 1 of 5 doi:10.1017/S1431927610093906
  • Blinka, E.*, D.A. HERBERT, Jr., S. Malone, J.W. Van Duyn, P. Roberts, J.R. Bradley, and J.S. Bacheler.  2010.  Relationship between external stink bug (Hemiptera: Pentatomidae) boll-feeding symptoms and internal boll damage with respect to cotton lint gin-out and fiber quality.  J. Econ. Entomol. 103: 2236-2241.
  • Kamminga, K.L.*, D.A. HERBERT, Jr., T.P. Kuhar, S. Malone, and H. Doughty.  2009.  Toxicity, feeding preference, and repellency associated with selected organic insecticides against Acrosternum hilare and Euschistus servus (Hemiptera: Pentatomidae).  J. Econ. Entomol. 102: 1915-1921.
  • Kamminga, K.L.*, D.A. HERBERT, Jr., T.P. Kuhar, S. Malone, and A. Koppel*.  2009. Efficacy of insecticides against Acrosternum hilare and Euschistus servus (Hemiptera: Pentatomidae) in Virginia and North Carolina.   J. Entomol. Sci. 44: 1-10.
  • Kamminga, K.L.*, D. A. HERBERT, T.P. Kuhar, and C. Brewster. 2009.  Predicting black light trap catch and flight activity of Acrosternum hilare (Hemiptera: Pentatomidae) adults.  Environ. Entomol. 38: 1716-1723.
  • Koppel, A.L.*, D.A. HERBERT, Jr., T.P. Kuhar, and K. Kamminga*.  2009.  Survey of stink bug (Hemiptera: Pentatomidae) egg parasitoids in wheat, soybean, and vegetable crops in southeast Virginia.  Environ. Entomol. 38: 375-379.
  • O’Berry, N.*, J.C. Faircloth, M. Jones, D.A. HERBERT, Jr., A.O. Abaye, T. McKemie, and C. Brownie.  2009.  Differential responses of cotton cultivars when applying mepiquat pentaborate.  Agron. J. 101: 25-31.
  • Toews, M.D., E.L. Blinka*, J.W. Van Duyn, D.A. HERBERT, Jr., J.S. Bacheler, P.M. Roberts, and J.K. Greene.  2009.  Fidelity of external boll feeding lesions to internal damage for assessing stink bug damage in cotton.  J. Econ. Entomol. 102: 1344-1351.
  • Leppla, N., D.A. HERBERT, and D. Thomas.  2009.  Functions, evolution and benefits of state integrated pest management programs.  Amer. Entomol.  55: 214-222.
  • O’Berry, N.B.*, J.C. Faircloth, K.L. Edmisten, G.D. Collins, A.M. Stewart, A.O. Abaye, D.A. HERBERT, Jr., and R.A. Haygood.  2008.  Trifloxysulfuron-sodium application does not provide season-long plant height control or hasten maturity of cotton (Gossypium hirsutum L.).  J. Cotton Sci.  12: 378-385.
  • HERBERT, D.A., Jr., S. Malone, T.P. Kuhar, H.E. Portillo, J.P. Saienni, and R.W. Williams.  2008.  Adult corn earworm (Helicoverpa zea) susceptibility to methomyl.  Online.  Plant Health Progress doi: 1.1094/PHP-2008-0312-01-RS.
  • O'Berry, N.B.*, J.C. Faircloth, K.L. Edmisten, G.D. Collins, A.M Stewart, A.O, Abaye, D.A. HERBERT, and R.A. Haygood.  2008. Plant population and planting date effects on cotton (Gossypium hirsutum L.) growth and yield. J. Cotton Sci. 12:178-187.

Selected numbered extension publications

  • Holshouser, D., D.A. HERBERT, P.M. Phipps, and M. Reiter. 2013. Troubleshooting the Soybean Crop. VCE Publ. AREC-25NP.

  • Flanders, K., D. Reisig, D. Buntin, M. Winslow, D.A. HERBERT, and D. Johnson.  2013. Biology and Management of Hessian Fly in the Southeast. VCE Publ. AREC-39 http://www.pubs.ext.vt.edu/AREC/AREC-39/AREC-39.html.
  • HERBERT, D. and S. Malone*.  2011. Second Edition, Mid-Atlantic Guide to the Insect Pests and Beneficials of Corn, Soybean and Small Grains. VCE Publ. 444-360.
  • Bacheler, J., D.A. HERBERT, Jr., J. Greene, P. Roberts, and E. Blinka*.  2010.  Scouting for stink bug damage in southeast cotton: description and use of a pocket scouting decision aid.  VCE Publ. 3005-1445.
  • HERBERT, D.A., Jr., E. Blinka*, J. Bacheler, J. Van Duyn, J. Greene, M. Toews, P. Roberts, and R. Smith.  2009.  Managing Stink Bugs in Cotton: Research in the Southeast Region.  VCE Publ. 444-390.
  • Kamminga, K.*, D.A. HERBERT, Jr., S. Malone, T.P. Kuhar, and J. Greene.  2009.  Field Guide to Stink Bugs of Agricultural Importance in the Upper Southern Region and Mid-Atlantic States.  VCE Publ. 444-356.

View full list of publications.