Grazed winter Cereals
At the end of 2021 Ross decided to graze his winter barley and winter wheat. On the 18th of November he fenced a field of each cereal and put sheep on both crops. The 8ha wheat field had 337 sheep grazing, and the 13ha winter barley field had 245 sheep grazing. The sheep were left until the 6th of December, when they were moved to graze cover crops. Ross has found that both cereals have grown away from the grazing. Ross used temporary electric fencing, powered by a battery to keep the sheep in as the arable fields are without permanent fencing. However, due to the awkward shape of some of the fields, occasional wooden posts were used to change the direction of the fence and keep the wires tight.
Photos below (left to right) show grazed winter barley showing some regrowth; grazed winter wheat also showing regrowth; the temporary electric fencer and battery system used to control access to grazing in the arable fields, and an example of how permanent wooden posts were often used to support the electric fence to ensure it remained robust!
Grazing Cover Crops
As well as grazing cereals, Ross has been experimenting with ways to terminate cover crops. Ross has set up an on-farm trial in several fields: where some cover crops are grazed; some are flailed; and some are left to be sprayed off with glyphosate. Ross is also planning to use a crimper roller to terminate covers if the weather permits (-4°C or colder is required).
The flailed cover crop has little surface residue remaining as the small particle size has allowed the biomass to break down quickly. However, it was noted that the roots of the cover crop are still intact. Ross is planning to leave the flailed areas to see if there is any regrowth before deciding if this area needs desiccated prior to sowing.
Ross has left several areas untouched; this is to provide a comparison to the grazed and flailed areas. Ross plans to use glyphosate to terminate these areas, however, he is concerned that the high amount of biomass will cause nitrogen lock up in following crops if it has not broken down prior to sowing.
The cover crops have also provided significant grazing between grazing cereals. The area pictured above shows what is left after grazing, with only straw from the previous crop left on the soil surface. Surprisingly, there is little manure left on the soil surface, instead this has been washed in or incorporated by worms. The soil felt a little wetter on the top, potentially due to some surface capping.
Photos below show (left to right) the flailed cover crop residue; cover crop that has not been flailed or grazed; grazed cover crops – or what remains of them and the sheep grazing the cover crops.
Ross dug soil pits in each of the three treatment areas, as he is concerned that the grazing of flailing may cause soil compaction. Below are pictures of each soil block, with the flailed cover crop soil on the left, the intact cover crop in the middle and the grazed cover crop on the right hand side.
Although there was not a large difference between each soil block, the grazed soil was more easily broken up and had a higher worm count, even though this area is in a heavier part of the field. There was little difference noted between the flailed and the intact cover crop. All three soil blocks had roots present to the full spade depth and were abundant in worms.