Cover crops are an important part of our system for a good number of reasons. We’ve found them to be one of the best ways to protect our heavy clay soils over winter and maintain beneficial rooting structures all year round – supporting good soil structure. We are also looking this year at how livestock can be incorporated into this portion of our rotation to make the most of Winter biomass.
This year we’ve borrowed some of our neighbours’ ewes to graze off our cover crops. Alongside this, we reserved 10ha’s of Radish for a grazing versus rolling trial and 3ha’s of Oats to whole crop post grazing. After a total of five weeks of grazing the cover crops down, the sheep left the farm in mid-January.
Two different cover crop mixtures were grazed including a mixture of tillage and forage Radish, drilled directly into chopped Wheat stubble, and an Oat cover crop drilled into OSR volunteers. After the sheep had made short work of the Radish, the field looked like it been bedded down, with the layer of chopped residue emerging beneath. In a wet Winter, I feel this could be a real advantage, providing a buffer between hoof and soil.
Our first field of Radish that was grazed off coincided with a sharp frost, which resulted in a total kill of the plant as stalks became brittle – a double whammy and an excellent result I thought! The traffic of hooves across the ground, coupled with an inch of rain and mild weather, provided the optimum conditions for a flush of weeds. This will prove ideal for when we go in with a single pass of Glyphosate ahead of spring drilling.
As an alternative method of cover crop termination trial, we split 10ha of Radish into two plots. One half grazed, and the other half Cambridge rolled on a hard frost. The rolling method has proved successful for me in the past, as I’ve found the frost carries the weight of the tractor well. The plants are also at their most brittle at this stage and generally more ‘receptive’ to the roll!
The only difficult part of this method is getting out of bed in the small hours of the morning on a cold winter’s day!
We hope the two methods will make for an interesting comparison come drilling. In a wet Winter, when we may be more reluctant to have sheep across our heavy clay soils, we will have an alternative low-cost mechanical way to help maintain the efficacy of Glyphosate in our system.
As an alternative cover crop, with grazing in mind, we drilled Oats into OSR stubble. The Oats went on to give us another excellent low-cost cover crop option. Our discerning diners grazed the volunteer OSR first, followed closely by the Oat main course.
During November’s Open Days, we took a closer look at the Oat grazing mixture and the condition of the soil beneath. Many visitors commented on the prospect of taking the oats through to harvest and, with this in mind, I’ve set aside 3ha to whole crop. The ewes had grazed down a considerable amount of biomass and cleaned up any mildew meaning the Oats head into spring clean.
After only 20 days post grazing, the plants had considerable regrowth and I’m eager to take it through to whole crop in late May/early June. This will hopefully give us an opportunity to grow a summer catch crop – something to keep your eye out for over the coming months.