Phillip Sylvester, Extension Agent – Agriculture, Kent County, philllip@udel.edu; Jarrod O. Miller, Extension Agronomist, jarrod@udel.edu; Cory Whaley, Extension Agent – Agriculture, Sussex County, whaley@udel.edu; Amy Shober, Extension Specialist – Nutrient Management and Environmental Quality, ashober@udel.edu; Mark VanGessel, Extension Weed Science Specialist, mjv@udel.edu; Bill Cissel, Extension IPM Agent, bcissel@udel.edu; and Alyssa Collins, Extension Plant Pathologist (Penn State), collins@psu.edu
Winter wheat and barley planting season will be here soon. Now is a good time to review yield, test weight, and disease resistance data from land-grant university variety trials. This data will help you select varieties adapted to our region. Seed may be in short supply this year, so be sure to inquire about availability as soon as possible. Here are some suggestions to help you get the most out of your small grains as we head into the fall.
Determine if small grains are profitable for your own operation. The idea that a small grain crop pays for itself and double crop soybean crop seed is antiquated. Small grains have become an intensive crop to grow in our region, mainly due to an increase in Fusarium head blight (FHB), which is also known as head scab. We suggest that you complete a crop budget using your own realistic yields, input prices, and expected grain prices. According to USDA-NASS, average wheat and barley yields in Delaware hover around 65-70 and 80-85 bushels per acre, respectively. Remember, the crop budgets are only as good as the information you enter.
Select varieties with disease tolerance or resistance, particularly for FHB. Although complete resistance for FHB does not yet exist in commercial wheat varieties, researchers have shown that planting a moderately resistant variety, in combination with a well-timed fungicide application at flowering, will significantly lower mycotoxin (i.e. DON) levels compared to a susceptible variety. Now is the time to take the first step toward FHB management by planting a moderately resistant variety.
Read this article about managing Fusarium head blight in 2019. Pay special attention to the part about not relying on fungicides alone for FHB management.
Review land-grant university data from local misted nurseries to determine if your wheat variety has some resistance against FHB. Researchers screen many commercial varieties for resistance levels by creating an extremely favorable environment for FHB in the misted nursery over the entire time a variety is flowering. We are fortunate to have a couple misted nurseries in the region, including one in Maryland and another in Virginia. Select a high yield variety, with good test weight based on land-grant university performance data from Delaware, Maryland, and Virginia.
Look for varieties that also have good resistance against powdery mildew, leaf blotch complex (i.e. tan spot, stagonospora, and septoria), and glume blotch. Although there has been a lot of focus surrounding FHB, don’t forget that these common foliar diseases can also be managed by planting resistant varieties. Avoid varieties that are completely susceptible to our common foliar diseases. This may prevent you from having to make a difficult fungicide timing decision as you approach flowering.
Clean any seed you saved legally from the previous harvest before planting. University of Maryland provides information about which varieties of seed can be saved legally. Be wary of seed that came from fields that were infected with glume blotch, smut, or scab. It may be useful to take a sample, clean it, and then send to a lab for germ testing. (Delaware Department of Agriculture can do this testing for a nominal fee.) Avoid using low germ seed. Commercial purchased seed is required to have a tag with germination rates, along with information about purity and weed seed. It would not hurt to ask for a copy prior to planting seed.
Perform a germination test on any seed you have saved. The University of Maine has an easy method for estimating germination using paper towels to simulate soil. Be sure to use at least 20-25 seeds in your germination test to get an accurate test.
Consider planting small grains following soybeans, rather than corn. Fusarium head blight is caused by a fungal pathogen that also causes disease in corn. The fungus overwinters on corn residue, so planting small grains after full season soybeans may reduce field level pressure from FHB. Furthermore, there may be an opportunity to skip the tillage passes because there is less residue to deal with.
Some type of tillage may be helpful if you are going to plant small grains after corn. Practices which bury corn residue can result in lower field level pressure from FHB. If you use vertical tillage implements, consider making multiple passes to facilitate the breakdown of corn residue into smaller pieces. Make the first pass right after harvest, following up with additional passes prior to planting. Do not forget to include the cost of tillage in your crop budget. Another reason to for tillage is uniform crop emergence. When late tillers push up as a result of uneven residue, they flower later than the main stems. This will make timing your scab control fungicide application very challenging.
Consider using a seed treatment fungicide. These treatments do a good job against pathogens that can be carried over on or in seed like the bunts and smuts, glume blotch and scab. Treatments are also effective at reducing stand and yield loss from seed rots and early season diseases like those caused by Fusarium, Pythium and Rhizoctonia. This can be especially important if planting is delayed and the seed bed is cool and wet. Fungicidal treatments will not provide control of bacterial diseases or viruses. Seed treatment will also not protect your wheat and barley from the head scab that occurs in the spring, it only provides protection for the damping off that may occur at germination as the result of planting some scabby seed.
Read this factsheet about Barley Yellow Dwarf in Small Grains. Four common species of aphids can infest small grains in Delaware and all species are capable of vectoring Barley Yellow Dwarf (BYD) virus. However, the economic impact from BYD is still unclear in Delaware. Furthermore, only the green bug aphid is known to cause direct damage to small grains in the fall. If BYD or green bug aphids have been a problem in the past in your fields, and you suffered economic losses, consider implementing management options outlined in the factsheet.
Take a soil test prior to planting small grains and make a fertilizer application, if needed. Fall is a great time for soil sampling. The University of Delaware recommends application of small amount of nitrogen at planting. You can save some money by combining nitrogen, phosphorus, and potassium into one mix (provided all these nutrients are needed). Be sure to follow your nutrient management plan. The target pH for small grains is 6.0; do NOT apply lime if your soil pH is higher than 6.0. Manganese deficiencies in barley and wheat are common in some parts of the state, and can be induced when the pH reaches 6.3 or above. If your soil test is already above 6.0, consider adding manganese to your mix, or making a foliar Mn application in the spring.
Be sure to control weeds prior to or at planting. Conventional tillage with chisel plowing will eliminate weeds present at planting, but if planting no-till or relying on vertical tillage, then use a non-selective herbicide (paraquat or glyphosate) to control emerged weeds. Vertical tillage is not an effective method of killing weeds. Zidua or Anthem (same active ingredients) can be applied once the wheat has begun to spike through the soil; applications prior to this time can result in significant crop injury. Zidua or Antem are not labeled for barley. Consider a fall herbicide application for fields with heavy weed pressure, or fields with Italian ryegrass, or planted early in the fall; refer to the Mid Atlantic Weed Management Guide for options. Fall herbicide options may not eliminate the need for a spring application, but applications in the fall are more consistent and provide more herbicide options. Furthermore, with the mild winters we have had, winter annual weeds are larger and more robust at time of spring applications and often the small grain crop interferes with getting good herbicide coverage.
Plant small grains during the optimal window to give the plants plenty of time to germinate and produce fall tillers, which are important for achieving maximum yield. The optimal time to plant barley is in the first half of October; the optimal time to plant wheat is within the two-week period following the Hessian fly-free date (New Castle: Oct. 3, Kent: Oct. 8, and Sussex: Oct. 10). Yes, we have all heard the stories of planting wheat in December and the ex post facto claims of “yielded just fine”. Sure, you can plant that late, just like you can plant corn in June and soybeans in August. However, they will not, on average, produce the highest yields. Be warned-planting prior to these dates can cause too much growth, and can serve as an attractive host to unwanted insect pests, such as aphids and Hessian fly, and foliar disease.
Plant 30-35 live seeds per square foot (1.3-1.5 million live seeds per acre). To convert to seeds per foot of row, multiple seeds per square foot × (row width/12). For example, 35 seeds per square foot × (0.625 for 7.5 in rows) = 22 seeds per foot of row. We do not recommend using pounds (bushels) per acre because seed size can vary greatly between varieties. Ask for the seed size prior to purchasing seed so you can purchase the correct quantity. Seeds should be planted at a depth of 1-1.5 inches. Steps for drill calibration can be found in section 4 of this guide from the University of Kentucky.
Walk your fields after planting. After emergence, take stand counts and monitor the crop for insects, diseases, and weeds.