Average nightly black light trap captures of corn earworm moths this week were: Chesapeake=33; Greensville=13; Southampton=10; Suffolk=27. Hanover had 12 per night if averaged over the past 2 nights, but 3 if averaged over the entire week. Here is the table:
In our corn earworm pyrethroid resistance monitoring experiment (adult vial tests), the seasonal average is 36% survival to a 24-hour exposure of 5 micrograms of cypermethrin per vial.
Nightly corn earworm/bollworm moth averages for reporting black light trap stations this week were: Greensville=22; Prince George (Templeton)=12; Prince George (Disputanta)=10; Southampton=13; Suffolk=32. Please see the link to the table below and also compare this year’s Suffolk, VA numbers to the past several years.
I have seen a large number of corn earworm moths in our soybean at the Tidewater Agricultural Research & Extension Center in Suffolk this week. Remember to scout for larvae and use the threshold calculator for soybean: https://www.ces.ncsu.edu/wp-content/uploads/2017/08/CEW-calculator-v0.006.html
Our pheromone trap catches at Suffolk have also increased and we were able to conduct more adult vial tests for resistance monitoring using the pyrethroid cypermethrin. The average survival for this season is now 37%.
Nightly captures of corn earworm (bollworm) moths in area black light traps greatly increased in Greensville this week (averaging 54 per night). Other reporting stations averaged from 6-7 per night in Prince George, 8 in Hanover, 16 in Chesapeake, 16 in Warsaw, and 22 in Suffolk. Please see the table here:
For soybean that is at or near the beginning pod (R3) stage, it is time to consider whether or not a fungicide application is needed to control foliar diseases and protect yield. Most of the soybean in Virginia is past the beginning pod (R3) stage, and fungicide applications are more likely to be profitable when applied at or near R3/R4. The Virginia soybean fungicide advisory indicates that disease risk is variable across the state. Fields with moderate risk should be scouted since foliar diseases will not be an issue in every field every year. Keep in mind that other risk factors also contribute to disease severity and yield loss to fungal diseases. High risk fields include those where susceptible soybean varieties are planted, there is a recent history of soybean foliar diseases, and/or rotations out of soybean are short or soybean is planted continuously over several years. Foliar fungicides are ineffective for control of most stem and root diseases. If based on the soybean fungicide advisory or other factors you decide to apply a fungicide, applications are generally the most effective when applied between R3 and R4 stages (no later than R5). The most recent Soybean Fungicide Efficacy Table can be downloaded from the Crop Protection Network website. Instructions on how to use the Virginia soybean fungicide advisory can be found in the July 19 blog post. A summary of disease risk and spray recommendations for different locations in Virginia can be found below. If you have any questions, contact Dr. Hillary Mehl (hlmehl@vt.edu).
| Region of Virginia | Location of weather station | Soybean disease risk | Recommendation |
| Eastern Shore | Painter | High | Spray |
| Southeastern | Suffolk | Moderate | Scout |
| Southeastern | Virginia Beach | High | Spray |
| Northern Neck | Warsaw | High | Spray |
| Central | Blackstone | Moderate | Scout |
| Northern | Middleburg | Moderate | Scout |
| Northern | Shenandoah | Moderate | Scout |
| Northern | Winchester | Low | Don’t spray |
| Western | Critz | High | Spray |
| Western | Blacksburg | High | Spray |
| Western | Glade Spring | High | Spray |
For detailed daily advisories, select the location closest to your field and download the corresponding file here:
For soybean that is at or near the beginning pod (R3) stage, it is time to consider whether or not a fungicide application is needed to control foliar diseases and protect yield. The Virginia soybean fungicide advisory indicates that disease risk is variable across the state. Fields with moderate risk should be scouted since foliar diseases will not be an issue in every field every year. Keep in mind that other risk factors also contribute to disease severity and yield loss to fungal diseases. High risk fields include those where susceptible soybean varieties are planted, there is a recent history of soybean foliar diseases, and/or rotations out of soybean are short or soybean is planted continuously over several years. If based on the soybean fungicide advisory or other factors you decide to apply a fungicide, applications are generally the most effective when applied between R3 and R4 stages (no later than R5). The most recent Soybean Fungicide Efficacy Table can be downloaded from the Crop Protection Network website. Instructions on how to use the Virginia soybean fungicide advisory can be found in the July 19 blog post. A summary of disease risk and spray recommendations for different locations in Virginia can be found below.
| Region of Virginia | Location of weather station | Soybean disease risk | Recommendation |
| Eastern Shore | Painter | High | Spray |
| Southeastern | Suffolk | Moderate | Scout |
| Southeastern | Virginia Beach | Moderate to high | Scout |
| Northern Neck | Warsaw | Moderate to high | Scout |
| Central | Blackstone | Moderate | Scout |
| Northern | Middleburg | Moderate to high | Scout |
| Northern | Shenandoah | High | Spray |
| Northern | Winchester | Low | Don’t spray |
| Western | Critz | High | Spray |
| Western | Blacksburg | Low | Don’t spray |
| Western | Glade Spring | High | Spray |
For detailed daily advisories, select the location closest to your field and download the corresponding file here:
Black light trap catches of H. zea (corn earworm/bollworm) moths increased at most locations this week. Please see the data table for more information.
We have tested 168 corn earworm moths in our cypermethrin vial tests so far this season, with a seasonal average of 39.5% survival. Here are the results by month (we’ll be conducting more tests throughout August):
We have updated our corn earworm survey of field corn (as a predictor of infestation risk in other crops such as soybean) to include Rockingham County’s 10.8% infested ears. Thanks to all cooperators for their efforts. Statewide average infested ears was 15.3% for 2019. The updated table and map are here:
For soybean that is at or near the beginning pod (R3) stage, it is time to consider whether or not a fungicide application is needed to control foliar diseases and protect yield. The Virginia soybean fungicide advisory indicates that disease risk is variable across the state. Fields with moderate risk should be scouted since foliar diseases will not be an issue in every field every year. Keep in mind that other risk factors also contribute to disease severity and yield loss to fungal diseases. High risk fields include those where susceptible soybean varieties are planted, there is a recent history of soybean foliar diseases, and/or rotations out of soybean are short or soybean is planted continuously over several years. If based on the soybean fungicide advisory or other factors you decide to apply a fungicide, applications are generally the most effective when applied between R3 and R4 stages (no later than R5). The most recent Soybean Fungicide Efficacy Table can be downloaded from the Crop Protection Network website. Instructions on how to use the Virginia soybean fungicide advisory can be found in the July 19 blog post. A summary of disease risk and spray recommendations for different locations in Virginia can be found below.
| Region of Virginia | Location of weather station | Soybean disease risk | Recommendation |
| Eastern Shore | Painter | High | Spray |
| Southeastern | Suffolk | Low to moderate | Don’t spray |
| Southeastern | Virginia Beach | Moderate | Scout |
| Northern Neck | Warsaw | Moderate to high | Scout |
| Central | Blackstone | Low | Don’t spray |
| Northern | Middleburg | Moderate to high | Scout |
| Northern | Shenandoah | Moderate to high | Scout |
| Northern | Winchester | Low to moderate | Don’t spray |
| Western | Critz | High | Spray |
| Western | Blacksburg | Moderate | Scout |
| Western | Glade Spring | High | Spray |
For detailed daily advisories, select the location closest to your field and download the corresponding file here:
If you have any questions, feel free to contact Dr. Hillary Mehl (hlmehl@vt.edu).
Corn earworm moth catches are increasing for most black light stations; nightly averages this week were: Greensville=25.1; Prince George (Templeton)=5.7; Prince George (Disputanta)=3.7; Warsaw=46.4; Southampton=9.0; Suffolk=14.6.
Preliminary results from our annual survey of field corn show the following percent infested ears (based on sampling 5 corn fields/county, 50 ears per field, for evidence of corn earworm larvae): Accomack=16.0 percent infested ears; Amelia=15.6; Chesapeake=5.6; Dinwiddie=19.6; Essex=11.6; Greensville=32.8; Hanover=32.8; Isle of Wight=17.6; King & Queen=13.6; King William=24.4; Lancaster=4.8; Northampton=11.2; Northumberland=4.0; Prince George=12.8; Southampton=11.2; Virginia Beach=17.6; Westmoreland=12.8. Thanks to the following for collecting data from their counties: Eastern Shore AREC entomology; Laura Siegle; Watson Lawrence; Mike Parrish; Robbie Longest and Brittany Semko; Sara Rutherford; Laura Maxey-Nay; Livvy Preisser; Trent Jones; Scott Reiter; Joshua Holland; Roy, Bailey, and Fletcher Flanagan; and Stephanie Romelczyk and Amerah Thompson.
We have found bollworm eggs and small larvae in our cotton experiment in Suffolk. Please be sure to scout your fields.
For soybean that is at or near the beginning pod (R3) stage, it is time to consider whether or not a fungicide application is needed to control foliar diseases and protect yield. The Virginia soybean fungicide advisory indicates that disease risk is moderate to high in most locations. Fields with moderate risk should be scouted since foliar diseases will not be an issue in every field every year. Keep in mind that other risk factors also contribute to disease severity and yield loss to fungal diseases. High risk fields include those where susceptible soybean varieties are planted, there is a recent history of soybean foliar diseases, and/or rotations out of soybean are short or soybean is planted continuously over several years. If based on the soybean fungicide advisory or other factors you decide to apply a fungicide, applications are generally the most effective when applied between R3 and R4 stages (no later than R5). The most recent Soybean Fungicide Efficacy Table and instructions on how to use the Virginia soybean fungicide advisory can be found in last week’s blog post. A summary of disease risk and spray recommendations for different locations in Virginia can be found below.
| Region of Virginia | Location of weather station | Soybean disease risk | Recommendation |
| Eastern Shore | Painter | High | Spray |
| Southeastern | Suffolk | Moderate | Scout |
| Southeastern | Virginia Beach | Moderate | Scout |
| Northern Neck | Warsaw | Moderate to high | Scout |
| Central | Blackstone | Low to moderate | Don’t spray |
| Northern | Middleburg | Moderate to high | Scout |
| Northern | Shenandoah | High | Spray |
| Northern | Winchester | Moderate | Scout |
| Western | Critz | High | Spray |
| Western | Blacksburg | High | Spray |
| Western | Glade Spring | High | Spray |
For detailed daily advisories, select the location closest to your field and download the corresponding file here:
If you have any questions, feel free to contact Dr. Hillary Mehl (hlmehl@vt.edu).
As August approaches, now is the time to be scouting peanuts for leaf spot and soilborne diseases and making timely fungicide applications. Calendar-based or advisory-based spray programs can be followed, but be sure to make your fungicide applications before rainy weather makes it difficult to get into fields. Many of our leaf spot outbreaks over the past couple of years were due to extended periods of rainfall and delayed fungicide applications. Cooler, wet weather over the past several days has increased the risk for Sclerotinia blight. In our research plots at the Tidewater AREC, we found small amounts of late leaf spot, Sclerotinia blight, and southern stem rot this week. The leaf spot and Sclerotinia blight advisories, which can be found on the Peanut Cotton Infonet website, indicate disease risk is currently high. For fungicide recommendations, contact your county extension agent or Dr. Hillary Mehl (hlmehl@vt.edu).
