Jordan Lonborg of Tablas Creek on crimper-rolling cover crops

Jordan selects a cover crop that is majority rigid grass species that can fold over without re-growing once crimper rolled, leaving a mat of biomass on the soil. This protects the soil from the sun and creates a microclimate conducive to beneficial bacteria and fungi, trapping moisture in the soil, keeping temperatures down.
Without mycorrhizal fungi plants can't access nutrients in the soil. Crimping provides the missing link, mycorrhizal fungi to create symbiotic relationship with grapevine roots, converting nutrients to useable form.
The downsides to crimping include providing a safe environment for rodents (gophers and ground squirrels) away from owls etc. He has been told of concerns re competition with vines decreasing vigour. However, the other options are disking which disrupts the mycorrhizal networks, mowing which exposes the soil to the heat of the sun, and chemicals which have never been an option for Tablas Creek.