Cover Crop Chats - Managing Manure
Cover crops can be a great way to manage manure, or lack thereof…. Let’s talk about how to put your legumes to work and when to make sure you have grasses and non-legume broadleaves with them.
Lazy Legumes -
Everyone wants their cover crop to work for them, especially when it comes to legumes fixing nitrogen. If you are not a producer that has manure to spread on fields after harvested crops, a blend heavy on legumes is a very good option to fix nitrogen and provide other nutrients for your soil. Where manure is applied, legumes don’t do as much work for you as they should. Legumes in those areas have plenty of soil nitrogen available, so they don’t need to give up any energy to connect with rhizobia and fix nitrogen. This creates those lazy legumes... So, what should be the focus in a mix where manure is applied? Catch Crops.
What is a Catch Crop? -
A catch crop will take up the available nitrogen and other nutrients that your manure contains and hold on to it for you. Grasses and non-legume broadleaves are the ticket here. Without the ability to fix their own nitrogen, these crops are very efficient in using their fibrous roots or tap roots to grab available nutrients. Those valuable nutrients cannot be lost to wind or water erosion or volatilization if they are safely tucked away in plant tissues. When your catch crop is terminated, those nutrients from your manure are put back into the soil where you need them.
None of this is to say you should not combine grasses and broadleaf plants with legumes. Please do! This is more about choosing what the goal of your cover crop is. No manure to spread? Focus heavier on the legumes, but still have the other species in there for forage quality and diversity. Have plenty of manure to spread? Still use legumes in the blend with your catch crop for the root diversity and added forage protein.
BONUS: The Pasture Side of Things –
This overall concept leaks over into the pasture world as well! Aside from the forage quality value that legumes and grasses have together, this symbiotic growth is another reason we recommend the pairing!
Focus on your goals, and choose the cover crop or “catch crop” that is right for you!