After looking at some wheat fields this morning I believe most of Virginia’s wheat is between head emergence (Feekes 10.3) and flowering (10.5.1). Wheat disease pressure has been low but with rain chances increasing by the middle of next week that could change. I have seen some physiological damage caused by weather or hypersensitive responses (resistant responses) to disease but no real disease outbreaks. With the flowering stage here we typically begin spraying for wheat scab or Fusarium head blight (FHB). Right now risk of FHB is low. The risk of FHB can be monitored by the FHB Risk Assessment Tool provided by Penn State (http://www.wheatscab.psu.edu/). Fungicides such as Caramba, Prosaro, and Miravis Ace are recommended for FHB and DON control. Caramba and Prosaro will provide better control when applied at flowering while Miravis Ace has a wider window of activity from heading to 6 days after flowering. Remember to avoid using strobilurin (FRAC Group 11) fungicides after flag leaf as these fungicides can increase DON levels in grain. Fungicides applied for FHB will control the other major foliar wheat diseases. The 2019 Fungicide Efficacy for Wheat Diseases can be found at the following link. NCERA 184 Wheat fungicide table 2019_Final
If you have questions about wheat diseases you can reach me, David Langston, via e-mail or phone.
that Velum Total now has a name and label change. The new product is simply Velum. The insecticide imidacloprid has been dropped
from the product meaning that it no longer contains material to control thrips.
If you purchase the relabeled Velum product, you will need to apply an additional insecticide. I recommend Admire Pro or generic products that include the active ingredient imidacloprid. Granular alternatives in peanut include Thimet 20G (phorate) and AgLogic 15G or 15GG (aldicarb). Refer to label rates.
Thrips are capable of causing yield loss and plant death in certain scenarios. I recommend that you use an in-furrow product in peanut. Foliar sprays are generally insufficient on their own, but may be warranted as an additional input in very high-pressure years. Cotton has the option of having insecticidal seed coating applied in addition or instead of using an in-furrow product (imidacloprid and aldicarb are labeled for both crops). Seed treatments alone require scouting and foliar sprays if warranted.
quantities of Velum Total as you ordinarily would.
The workshops will be virtual via Zoom on Tuesday Dec. 8th and Tuesday Dec. 15th. On both days, choose the time that works best for you: 8-10 am OR 6-8 pm. Optional in-person “watch party” meetings offered at several locations.
Topics:Session One: Tues Dec 8th 8-10 am OR 6-8 pm Herbicide Resistance- What is It? Mechanisms of Action-How to Choose Herbicides Creating Effective Herbicide Plans
Session Two: Tues Dec 15th 8-10 am OR 6-8 pm IWM with a focus on Palmer Amaranth, Common Ragweed, and Marestail Local Perspectives on Resistance Management Putting It All Together: Creating a Weed Management Plan
Speakers: Dr. Michael Flessner and Dr. Vijay Singh, Virginia Tech Dr. Mark VanGessel, University of Delaware Dr. Kurt Vollmer and Ben Beale, University of Maryland
CCA Credits will be offered. For More Information Contact: Ben Beale at 301-475-4481 or Kurt Vollmer at 410-827-8056 28
We have high numbers of fire ant mounds in our crop fields and around our farms this year. There have been some unfortunate encounters and this message is to make you aware of what these mounds look like and the potential for injury. Mounds look like large piles of loose dirt (keep in mind they have to start small at some point). They are often found around fence posts and mailboxes, but many are located in fields, pastures, and lawns. Field borders and paths are frequently infested. Fire ants sting, just like wasps and bees, and some people will be allergic and require medical interventions. People that are not allergic will have itchy, painful welts that often fill with fluid and may take days or a week or more to heal. Usually, you will have dozens or even hundreds of stings. This is because the swarm very fast and wait to sting all at once. Keep in mind that I have lived around them most of my adult life in North Carolina and we have come to accept them as part of our environment and have learned caution and awareness. I have been stung multiple times, usually once every few years, and usually when I am scouting crops. Be aware of where your feet are standing. Walk quickly when crossing a field because you can disturb them and get away without injury. Treatment options are below for mounds located near homes and barns. You do not want children or young animals near these things.
I would not attempt to clear your crop fields. A single acre can contain hundreds of mounds and millions of fire ants. Fire ants are predators and will eat caterpillars and other insect pests. They will not eat seeds and plants. Large mounds can damage equipment in rare cases. Products exist that can be applied to turf and lawns with year-long residuals (e.g., TopChoice). These products require a pesticide applicator license to purchase. Baits (e.g., Advion) are an alternative if you are not licensed to apply insecticides. These can be purchased online, many local retailers do not carry them yet. Surface treatments do not work because the colony can live very deep underground. Do not attempt to treat once the weather turns cold because it will not work. Wait until spring. Pray for a cold winter.
Be safe y’all and stay healthy. As always, reach out to me if you have questions or concerns. Keep in mind that I am NOT an urban or ornamental entomologist and I am NOT trying to sell you any specific product. FOLLOW THE LABEL WITH ANY INSECTICIDE.
Corn earworm moth black light trap catches were low this week, averaging from 2 to 6 per night (Greensville=3; Hanover=2; Southampton=6; Suffolk=2). Most trap operators will be shutting off their traps by the end of this month. We greatly appreciate the efforts of cooperating growers, Virginia Cooperative Extension Agents Mike Parrish, Sara Rutherford, Laura Maxey-Nay, Scott Reiter, and Josh Holland, and Tidewater Agricultural Research and Extension Center’s Daniel Espinosa. TABLE
With the exception of Hanover, trap captures have declined since last week. The average nightly corn earworm/bollworm moth black light trap captures for this week (rounded) were: Greensville=18; Hanover=7; Prince George-Templeton=3; Prince George-Disputanta=2; Southampton=8; Suffolk=38. Thanks to our trap operators for their reports! TABLE
Average nightly corn earworm/bollworm moth black light trap captures for this week were: Greensville=28; Prince George-Templeton=5.5; Prince George-Disputanta=7; Southampton=17; Suffolk=76. Here is the Table
For soybean, here is the tool that calculates the corn earworm larval threshold number based on user input values for sampling techinque (sweep net or beat cloth), cost of insecticide application, price of beans, and row width: threshold calculator
We have done 391 vial tests so far this season, with 35% of moths surviving the 24-hour exposure to the pyrethroid cypermethrin at the rate of 5 micrograms per vial.
Average nightly corn earworm/bollworm moth black light trap captures for this week were: Dinwiddie=54; Greensville=15; Prince George-Templeton=13; Prince George-Disputanta=11; Southampton=22; Suffolk=92. Here is the Table
We have 37% survival in our cypermethrin vial tests (338 corn earworm moths tested from Suffolk, VA).
This week, my PhD student, Sean Boyle, observed pickleworm holes in our zucchini and squash in Whitethorne, VA near Blacksburg. This is the first that we’ve seen this pest in 2020. If you have noticed this pest in your area, please let me know – email firstname.lastname@example.org. The pickleworm, Diaphania nitidalis (Stoll) is a tropical moth pest of cucurbit crops including pumpkins, squash, and cucumbers (Fig. 1). It is typically a pest in the southern U.S. and does not overwinter in Virginia. The past few years, the pest has made its way northward in late summer on wind and storm fronts. Several pumpkins growers in Virginia have suffered damage from this pest in since 2017 usually following some August summer storms.
Moths fly to flowering pumpkins, squash, or cucumbers and deposit their eggs. A single female moth can lay up to 400 eggs usually on cucurbit flowers. Larvae feed on flowers (Fig. 2) and bore into fruit leaving a characteristic perfectly round hole often with sawdust-like fecal material around it as well.
Management. Pickleworm is very difficult to predict or monitor for as eggs are very tiny, moths fly at night, but are not attracted to lights, and there is no commercially-available pheromone lure. As a result, cucurbit growers in the South often apply insecticides weekly during the fruiting stages until final harvest. Pyrethroid insecticides can be effective at controlling this pest if sprayed in a timely manner (i.e., lambda-cyhalothrin, permethrin, bifenthrin, Baythroid XL, Mustang Max, etc.). Pyrethroids are often used because of their low cost and because they also control squash bugs and cucumber beetles, but they are not IPM compatible and can result in outbreaks of secondary pests such as aphids. Usually two or more sprays of pyrethroids in late summer can cause severe aphid problems leading to honey dew build up on plants. Other insecticides that control pickleworm include: the spinosyn productss, Radiant and Entrust, the diamide insecticides, Coragen and Harvanta, the insect growth regulator (IGR) Intrepid, and the lepidopteran-targeting insecticide Avaunt eVo. All of these products will have less nontarget impacts than pyrethroids and will also control pickleworm.
Average nightly corn earworm/bollworm moth black light trap captures for this week were: Dinwiddie=48; Greensville=47; Hanover=2.5; Prince George-Templeton=18; Prince George-Disputanta=5; Southampton=13; Suffolk=41. Here is the Table