If there was ever a picture perfect fall season for cover crops, 2015 would absolutely be it! Rainfall was timely – there was sufficient precipitation in August and September – to help the freshly seeded cover crops germinate and kick start their fall growth. Beyond that, we’ve had beautifully mild temperatures for the majority of October and November.
While many parts of the state experienced freezing conditions back in October, cover crops are quite hardy – just one cold night that drops below the freezing point is not enough to knock them out! So as the fall marched on, the cover crops grew and grew…
However, winter-like weather has arrived this week, which meant it was high time for the Iowa Learning Farms team to get out there and take care of our fall field work responsibilities. As part of our National Conservation Innovation Grant/Cover Crop Mixtures demonstration project, we were collecting fall cover crop biomass at each of our demonstration sites across the state. In order to obtain the most accurate cover crop growth data, the collection of cover crop biomass is ideally done as close as possible to the time of an extended hard freeze – which is now looming very near. So Iowa Learning Farms team members have been “on the clock” this week trying to complete all of our fall field work and sampling before the cold is here to stay!
Included below are a number of photographs from our cover crop mixture plots at the ISU Armstrong Research Farm near Lewis in southwest Iowa. These photographs were all taken on Wednesday, November 18. We hadn’t been back to the Armstrong Farm since the cover crops were seeded in early September, so it was thrilling to see the beautiful growth that has been achieved!
In the plots that had soybeans in ‘15 (going to corn in ’16), the cover crop treatments included:
Single species cover crop (oats)
Cover crop mixture (oats, hairy vetch, and radish)
Now in the third year of this project, this is the first time that we really definitively saw strong growth of all species in the mixture!
While there is no denying the amount of intrigue in using radishes as a cover crop, we typically have not seen as much success with it in Iowa when compared to other states, due to our shorter window of opportunity for fall growth. This year is turning out to be a good year for the radish, as well. Healthy radish growth was found throughout our mixture plots, with many radishes forming tubers around 1/2” in diameter. However, there were a few big boys that just went crazy…
Moving across the farm to our corn plots (going to beans in ’16), the cover crop treatments included:
Single species cover crop (cereal rye)
Cover crop mixture (rye, rapeseed, and radish)
While the dates of cover crop planting and growing conditions (temperature, precipitation, sunlight – as related to leaf drop/canopy opening with the cash crop) certainly vary across the state, it is exciting to see such vibrant cover crop growth this fall.
How are the cover crops looking in your area? We’d love to see any photographs that you may have. Send them to us at email@example.com, or share with Iowa Learning Farms on social media (we’re on Facebook and Twitter).