Winter rye also called cereal rye is growing well in these warm days of spring. There are advantages to turning under now while it's still succulent. There is less nitrogen tie-up than waiting until later when it develops stout stems. Remember to allow at least a month after turning under before planting.
Winter rye (not Italian ryegrass which is different) is one of the hardiest cereals and is also drought tolerant. It can be planted early or late in fall, either by itself or with a legume such as hairy vetch or Austrian winter pea for adding nitrogen.
By itself it will scavenge soil nitrogen from last season and keep it from leaching over the winter. It grows well on sandy soils and is good for preventing wind erosion. Rye produces a lot of biomass adding to soil organic matter.
You can also leave a row of rye to shield early planted vegetables from spring winds. Peas, lettuce and other cold soil tolerant crops can now be seeded as soils should be well over 40 degrees F along most of the Front Range.
Photo credit: Winter rye closeup and in bed - Carl Wilson