Grateful for a nice week for harvesting and for the good yields being reported! It’s also good to see cattle being turned into cornstalks. A reminder to read herbicide labels to understand if there’s any grazing restrictions from corn and soybean herbicides applied in-season.
It’s also important to look for any grazing restrictions on fall-applied herbicides to control marestail and other germinating weeds. These restrictions can also be found in the Forage Feed Grazing Restrictions in the UNL Guide for Weed Management. The forage, feed, and grazing restriction only applies to the crop for which the herbicide was applied. When it comes to grazing cover crops planted into these residues, one must use the replant/rotation restriction guidelines found on the herbicide label and in the UNL Weed Guide: Replant Options Rotation Restrictions-long. I apologize as these scanned blurry; hopefully you can zoom in ok to read what you need.
If the label doesn’t specify any restrictions, then it should be ok. If you want to be on the safe side, a rule of thumb is to use the pre-harvest interval for the amount of time to wait before grazing stalks. Some labels will say that residue should not be grazed or baled and fed to livestock. Sometimes studies were actually conducted to know there is a safety concern. In other cases, the chemical company may not choose to conduct all the studies the Environmental Protection Agency (EPA) required for labeling due to high costs. If that’s the case, the EPA requires the strongest restrictive language be placed on the label. Regardless, if it says there’s a grazing restriction on the label, the label needs to be followed as it is a legal document and the law.
As you plan for next year’s herbicide program, if you’re thinking about fall cover crops, the following NebGuide may be of benefit to you as it goes through the grazing restrictions of various herbicides.
During the summer, our crops extension team has some great field days to share research and management strategies to farmers. One of those opportunities to learn more about weed management and cover crops will be on June 28 at the South Central Agricultural Laboratory near Clay Center. There is no charge for the field day […]
Happy New Year! Wishing all of you and your families a wonderful 2015! As I look back at 2014, there are several ag-related observations that I noted throughout the year.
The first observation continues to be the way communities and people in this County/area pull together in difficult times. Whether after tornadoes/wind storms or helping other farm families who had an injured family member or had lost a family member, it’s just a blessing to see the way people pull together to help each other in time of need. It was also a blessing for many who were unable to harvest in 2013 due to the August 1st storm, to harvest fields in 2014, and for many in the area to experience really good irrigated and dryland yields this year.
The dry winter of 2013/14 allowed for very mellow ground during planting time. Often seeding depth ended up ½-1” deeper than intended. The dry winter also didn’t allow for good residue decomposition leading to problems during planting and ensuing stand emergence. Cutting off residue and high rains in May led to unintended consequences of replant situations when residue was moved off of farmers’ fields onto neighboring fields, suffocating emerged plants in portions of fields. I’m not sure what the solution is for the future other than it really needs to be something worked out with neighboring farmers, but perhaps mentioning it here opens an opportunity for future conversations.
Cover crops have been incorporated into more operations in recent years, yet the ultimate goal for using them remains important in determining what species/crops are used in the fields. We also realized the importance of determining amount grazed prior to turning cattle into fields (whether for grazing cover crops or crop residue), as high winds in winter 2013/14 in overgrazed fields led to soil blowing throughout the winter.
The May frost showed us emerged soybeans at the cotyledon stage held up well to the frost compared to the corn. We also again watched Goss’ wilt show up systemically by 6 leaf corn that was injured early by frost or hail in fields where Goss’ wilt had been a problem in the past. We need more research/understanding of this disease. Wheat continues to show us its resiliency as it winterkilled in portions of fields, withstood drought-stress, and then made up yield in the last 4-6 weeks.
Perfect pollination conditions coupled with high solar radiation, low night-time temperatures, and timely rain events were keys to the bountiful corn crop we experienced this year. Soybeans were more of a mixed bag. In walking fields and in conversations with farmers, I think the disappointment in some irrigated yields could be attributed to early/over-irrigation, disease problems, and planting date. UNL on-farm research showed on average a 3 bu/ac yield increase when soybeans were planted in late April to first week of May (regardless if growing season was warm/dry or cold/wet like it was this year) and those I’ve talked to who achieved 80+ bu/ac in the area this year planted in that time-frame. I’m curious if there’s something to planting a 2.4-2.5 maturity early vs. a 3.0+ maturity early as some area producers are seeing strong yields from a shorter season hybrid planted early the past few years. So if you’ve also seen this and/or are interested, that will be an on-farm research project to try next year. Please let me know if you’re interested!
Here’s wishing you a healthy and prosperous 2015!
A common question lately has been “I’m considering planting cover crops into areas of corn and soybean fields with hail damage. What are my next steps?”
First, it’s important to consult your crop insurance provider to determine if you can do anything before the adjuster examines the field.
Next, look at your cover crop options, based on potential herbicide carryover from the previous crop and what your end goal is for the cover crop.
Herbicide carryover from the corn or soybean crop also can be a concern. Check out the herbicide carryover replant options in UNL Extension’s Guide for Weed Management with Insecticide and Fungicide Information on pages 160-171.
To determine if herbicide carryover is a concern for your fields, first check the herbicide label(s) for potential problems. If a rotation (waiting) interval is a concern, contact the chemical manufacturer and explain your conditions. Although the label is the law, companies have conducted extensive research on their products. Sometimes, they can give you a percentage survival chance for planting a crop within a cropping interval. Producers will assume the risk if the germination of the next crop is severely affected, but it may be worth a small calculated risk to potentially get a cover crop established.
Home germination tests also can be conducted. (Planting delays with cover crops, though, may be a concern). Simply take soil samples from the hailed fields and place into containers such as plastic cups with holes in the bottom. Plant about 20 seeds per cup of whichever cover crops you are interested in and wait 7-14 days to determine percent germination. If you don’t have seed, check a cover crop seed supplier to request some free seeds for testing.
Select Seed to Match Your Need
Know what your goal is for the cover crop in order to determine what to plant. Do you want to capture the nitrogen already in these fields? Both legume and non-legume cover crops can capture soil profile nitrogen in their plant tissues for release in subsequent seasons. Late summer or early fall seeded cover crops favor the brassicas (turnips; oilseed radishes including Tillage Radishes®; and canola) for nitrogen trapping for the next crop. Oats make a good complement to seed with the brassicas, since the oats provide quick, weed-suppressing biomass while taking up excess soil nutrients. These plants can survive a light frost and keep on growing.
If reducing compaction is your concern, turnips may help with surface compaction while radishes provide a longer taproot to work through deeper compaction.
If forage is needed for haying or grazing, good choices would be winter annual grasses such as cold-tolerant “winter” oats, cereal rye, winter triticale, and winter wheat. Winter legumes such as yellow sweetclover and winterpeas also may be included in a mix with winter triticale to increase protein content; however, these legumes will need to be planted before early September to provide grazing benefits.
Corn and soybean fields also can be used for forage instead of grain. Silage is probably the best option when the moisture drops to 60%. Currently, the immature hailed corn fields are still about 80% moisture, so producers will either have to wait for the crop to dry or mix dry forages such as straw with the wetter silage in the right proportion. Conversely, if the plants get too dry, it will be hard to pack the silage. To check the moisture, harvest several stalks and chop into smaller pieces with a corn knife, and then test for moisture content. Usually, the feeding value of immature, hailed silage is similar to prairie hay based on nutrient content.
Grazing the hailed fields is another option. However, acidosis may be a concern if cows graze primarily on the immature ears. Cows should be fed some grain for a few days prior to turn out on the hailed fields to help their rumens adjust to a higher carbohydrate diet.
Haying and earlage also may be options, but forage curing is difficult with the cooler days, especially if ears don’t dry well on damaged stalks. Bruce Anderson, UNL Forage specialist, says that it takes 10-14 days longer to dry the damaged corn stalks after crimping than drying cane hay. So, the risk for mold potential on the forage is higher than moving the forage into silage.
Thanks to Todd Whitney, UNL Extension Educator, for his contributions to this article!