I want to start the year off by letting all of you know about some educational opportunities. Listed is a master list of commodity meetings offered throughout the state by Extension specialists. Please plan to attend meetings close to your location to stay abreast of what’s new and obtain pesticide credits.
A MS student in my laboratory has reported that egg lay has been extremely heavy over the past week. Because of the warm weather, Hessian flies in wheat planted during October have already turned over a generation and are emerging and laying eggs. Larvae will hatch from these eggs and larvae will feed throughout the cold months, killing any tillers that survived the first generation. Chances are slim that ground applications can be made due to El Niño’s gift of water (and more forecasted). If you can spray by air, here are some things to consider:
1) Spray only susceptible varieties. A list of high yielding varieties with Hessian fly resistance ratings (if known) can be found here.
2) Seed treatments have run out. They will not provide protection at this point, although they may have given you a head start by reducing initial populations.
3) Check your earliest planted wheat for Hessian fly larvae and pupae. A good way to do this is do take a shovel and carefully dig up plants. Keep all the soil on the shovel and dissect the plants. Focus in the soil on dead tillers that may have rotted; pupae and larvae may be harboring in these dead tillers that are not apparent on the surface.
4) See if you have eggs. A photo of an egg is provided in this earlier article. There is no threshold for spraying eggs, although we are working on developing one. I get worried when there is at least one egg per tiller.
5) Spray as soon as you can if there are eggs, but not right before a rain. We think that the insecticide works best if you can get some residual to kill adults. It is possible that the insecticide can kill larvae when they hatch from the eggs and move down the leaf to feed below the soil surface. A spray targeted when eggs first show up should work the best if these assumptions are true. See this article for an efficacy trial.
If you want more extensive coverage of all our recommendations and fly biology, they can be found in Biology and Management of Hessian Fly in the Southeast, the Small Grain Production Guide, or this video here.
Many farmers have not soil sampled this year due to wet conditions. It is not too late to submit soil samples to either the state or private soil test lab to measure nutrients for nutritional planning. Remember not to sample saturated fields for fear of erroneous pH readings and lime recommendations.
Expect to see serious surface compaction problems this year. Think about how much water weighs then think about how much rain we have had. There is approximately 27,154 gallons in 1 acre inch of water. Multiply inches of ponded water x 27,154 x the weight of water per gallon and you may be surprised how much weight and pressure has been applied to soil particles in the field. Some fields have good internal drainage while others do not. Help your farmers check for compaction issues when fields begin to dry out.
All of you could help your tobacco farmers by suggesting they test their water before seeding greenhouse. Simply run source water 30 minutes before collecting sample and collect 1 qt. of water in a clean plastic container. Results can be obtained from most labs within 3 days of submitting the sample. If there are concerns, there should be ample time to amend water quality before agronomic problems occur. If you need assistance during the year monitoring the health and general management of your clients greenhouses just give me a call.
Sincerely,
Rick