Start Scouting for Cutworm Injury in Corn
Many counties will hit the 300-degree day mark today, (5/22), and that means the first wave of BCW are big enough to start cutting corn plants. I was able to scout some corn this week and found cutworm feeding on leaves and a couple that the leaves were chewed off and lying next to the plant. This week, five of the six BCW traps had significant catches. With the multiple weeks of BCW significant flights after 4/24, the corn will need to be scouted the rest of the season until plants reach the V6 growth stage (6 collars visible). After this, the plants will be too big to cut. If 3 to 5% of the plants are missing or cut, spraying with an insecticide is warranted.
Big flights of armyworms continue to be caught in the Penn Yan trap. Growers in this area and Wyoming County should be scouting winter grains, grass fields and grass alfalfa seedlings. I have not had any reports of armyworm infestations yet. Look for signs of blackbirds flying into winter grain fields and sitting in trees and on power lines along the field. Guaranteed they are diving in there to feed on armyworms!
Wheat Beginning to Flower
I saw the first anthers emerged in a wheat field on Tuesday. Flowering will move quickly with the warmer weather. If you are unsure about what wheat flowering looks like, see this archived video we have on our YouTube page, https://www.youtube.com/watch?v=51xthmslywo&list=PLBMGyzTr13dsj4Ufdu6Dle2AJtGJbyo6z&index=6. See last week’s Crop Alert for an updated fungicide list.
Many fields will continue to head out and flower all week. There is an application window of approximately 7 days from the beginning of flowering in which reasonable Fusarium head blight (FHB) suppression can be expected. The Fusarium Risk Assessment Tool (http://www.wheatscab.psu.edu/ ) shows our region at high risk of infection the next four days and at medium risk at six days out.
Stripe Rust in Wheat is Here!
It has been many years since we have had an outbreak of stripe rust in NWNY. I was called to a field in Seneca County yesterday and unfortunately, it has a terrible rust infection. The field looked yellow-orange from a distance. Stripe rust usually starts out as small yellow areas but rapidly spreads and can take over the whole field rather quickly. Wheat fields are just starting to flower and it is so important to protect that flag leaf. I also talked with Gary Bergstrom and he had confirmed another case in Livingston County. The warmer weather should slow it down a little. It would be great if we could wait to spray our fungicide at flowering and take care of the stripe rust too.
- Egg hatch around 90 Degree Days
- Plant cutting around 300 Degree Days
- Degree Day data from Network for Environment and Weather Applications, NEWA
Summary of Alfalfa Height and Prediction of % NDF- May 22, 2024
1st Cutting Forage Quality Update
This is the fourth week of monitoring 1st cutting for quality this year. Our procedure consists of using alfalfa height to predict Neutral Detergent Fiber (NDF) for alfalfa, alfalfa/grass mixed, and grass stands. Alfalfa height has proven to be a reliable indicator of NDF values in the field.
Height indicators alfalfa and grass for NDF content are below:
- In general, we say 100% grass stands should be cut when nearby alfalfa is 14 inches tall to achieve the desired 50% NDF.
- Begin cutting 50/50 mixed alfalfa and grass stands when nearby alfalfa is 22 inches tall for the desired 44% NDF.
- Begin cutting 100% alfalfa stands when alfalfa is 28 inches tall for desired 40% NDF.
Predicted days to cut are based on daily NDF increases for grasses of 1% point, 50/50 mixed stands of 0.8% points and alfalfa of 0.5% point. NDF usually increases about 0.8 to 1.2/day for grasses expecting the lower end of that range in cooler weather and the higher end in warmer. Alfalfa NDF increases about 0.4 to 0.7/ day again depending on temperatures. Predictions are adjusted for the coming week’s weather and right now assuming normal growth.
In the attached spreadsheet locations around the region are listed where we have measured alfalfa height. You can use the location and elevation as a guide to conditions that may be like your farm.
As of today, May 22nd, 2024, alfalfa heights averaged 24 inches across all locations. An average growth of 6 inches. Grass stands are heading out and should be harvested. If you have not harvested, you should be thinking about which fields are going to be taken for quality forage or tonnage. Mixed stands should have been harvested last weekend. Pure alfalfa stands are read to harvest now!
It is important that you get first cutting off in a timely manner for quality purposes, so please communicate in advance with your team on how you are going to plant corn and successfully harvest 1st cutting.
This concludes our first cut monitoring program. We will be out scouting second cut regrowth and keep you informed of any insect pressure. See you in the field!
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Next report will be May 29.
