Repair & Recovery Options for Damaged Alfalfa
Last fall I walked some beautiful, healthy, vibrant alfalfa stands. This spring, it’s like a bad magic trick… Abracadabra! Presto! Our alfalfa has disappeared, but there’s no need to alert Matlock or James Bond. We already know the culprit is winter weather.
Our alfalfa crop has been on a wild ride for the past year. The 2012 drought created concerns for new alfalfa establishments. In some areas, during the heart of winter, there was inadequate snow to serve as insulation and protect alfalfa from winter injury. Cooler spring temperatures delayed when alfalfa plants would normally emerge from dormancy. Additionally, at the time dormancy was breaking, we were hit with a late season snow event.
The alfalfa damage we’re seeing now is a combination of many events:
- Smothered – This is the most probable cause of alfalfa injury in our area. It results from a combination of heavy, wet snow and ice packed tightly against crown prohibiting proper respiration.
- Reduced carbohydrates in crown – Last year’s drought reduced plant metabolism. Drought also reduced the plant’s ability to capture nutrients needed to build essential carbohydrates for such a long winter. The crown is like a gas tank for nutrients, and the long winter had alfalfa running on empty.
- Late fall cutting – With an alfalfa shortage from the 2012 drought, growers harvested as much as possible. This aggressive cutting regime took energy from the storage reserve in the crown, and the alfalfa plant struggled to replenish this reserve because of limited water. As a livestock producer, we needed the forage, and we had to do it.
- Reduced insulating barrier – Typically, snow helps insulate the soil and stabilize soil temperatures. In the absence of early season snow, alfalfa fields that were cut late didn’t have adequate insulation to protect against winter damage. On the contrary, fields that were not harvested late had some growth that acted as buffer between the snow, ice and crown.
- 2012 fall seeded alfalfa – Simply stated, there just wasn’t enough water needed for plant emergence, metabolism and carbohydrate storage.
Now that we understand why the damage occurred, it’s important to repair or recover what we can for the 2013 crop. There are many considerations to take into account including the age of stand, percent of damage in field, and the intended end use.
- Summer / fall seeded 2012 – most likely, you can reseed / interseed without autoxicity. Click here for an autoxicity worksheet.
- Older stands with light damage – interseed with a stand extender product such as Italian ryegrass or Bandito ryegrass. This will grow fast and thicken the stand. This is a temporary fix to get quick forage and will be suited for chopping. Seed rate varies depending on thickness of alfalfa stand. Click here for some university recommendations.
- Older stand with extensive damage – if you don’t need immediate forage, plan to rotate crops now. Remember, you have a nitrogen credit. This field will now grow great corn silage, and you can seed alfalfa into another field.
- New seeding – Due to a late spring, there’s still time to establish new seeding if it’s done quickly. Call your local seed rep today, however, because availability of alfalfa seed is becoming limited as a result of widespread winterkill.
- Alternative forage – If you’re in need of quick feed for cows, use what works best for you:
- Italian Ryegrass alfalfa mix interseeded into partial killed fields
- Oats and peas, underseeded with alfalfa. If you harvest early, you may get an extra cutting of alfalfa.
- Triticale and peas as triticale fast growing
- BMR Sudan Grass
- Forage Soybean