Our pasture restoration project has been ongoing for the past 3 years, and every year we continue to see improvement in the pasture quality and soil health. It is this time of year that we get out the seed ordered in the fall, and prepare for frost seeding. We incorporate our sheep in this process as well, which comes back to the idea of regenerative agriculture.
Regenerative Agriculture focuses on topsoil regeneration, increasing biodiversity, improving the water cycle, supporting biosequestration, increasing resilience to climate change, and strengthening the health and vitality of farm soil.
Today we worked on the back pasture, which was definitely the worst off when we first came to the farm in 2018. Last year we were able to get a stand of various dryland grasses established with the aid of frost seeding. Today we broadcasted a legume variety called Sainfoin. This is a new legume variety that we are excited to try because of the decreased risk of bloat that is commonly found with other legumes like alfalfa or clover.
Sainfoin is a nitrogen fixer, so Rhizobia in root nodules of sainfoin fix nitrogen and boost soil nitrogen. The roots penetrate to great depths and pull nutrients up from the subsoil. Sainfoin has been found to increase the sequestration of nutrients such as phosphate. It can be grown on thin, highly alkaline soils and is extremely tolerant of drought due to its deep rooting nature, growing through dry periods. It is ideally suited to stony brash and chalk, but does not thrive on heavy wet soils.
Seeding this time of year is referred to as frost seeding. Frost seeding involves spreading seed on frozen ground and allowing the freeze-thaw-freeze-thaw cycle that occurs as spring approaches to provide good seed-to-soil contact. When moisture in the top layer of soil freezes, ice expands upward, carrying soil with it. This process, called “heaving,” helps work seeds into the soil and creates good seed-to-soil contact. When early spring temperatures are optimal, the seeds will germinate.
After frost seeding, we move the sheep onto the pasture for about a week. The benefit of this is simple -- they walk around and push the seed into the soil. This helps to ensure good seed to soil contact. After about 1 week, we will pull the sheep off pasture to let the seeds germinate and grow.