In western Oregon, planting hairy vetch in mixtures with a cereal improves winter weed suppression. Some spring cereal varieties are likely to winter-kill if planted in early September, allowing the vetch to grow without competition in spring. Winter-kill susceptibility varies greatly among varieties. Cereals or grasses that do not winter-kill provide structural support for hairy vetch vines, preventing them from rotting by reducing contact with the soil. Because of hairy vetch's hard seeds and ability to reseed, it can become a serious weed problem in annual vegetable rotations.
Many growers prefer to use common vetch because it has fewer hard seeds.
On the other hand, the tendency to reseed is beneficial when hairy vetch is used as part of a permanent cover in orchards. When mowing in spring, let some strips go to seed. Hairy vetch normally will survive in Zone 4 or any warmer zone. If susceptible seed is planted shortly after incorporation, you may have more problems with this disease. Avoid this problem by waiting several weeks between residue incorporation and planting.