By: Sjoerd Willem Duiker

Small grains are mostly harvested across Pennsylvania and corn silage harvest will begin soon. Other crops such as snap beans and other vegetables may have been harvested as well. An important component of sustainable soil management is to keep soil covered at all times with living vegetation. That means planting cover crops as soon as possible after main crop harvest. Cover crops provide diversity in the landscape, protect soil from erosion, reduce runoff, increase infiltration, recycle nutrients from the subsoil, fix atmospheric nitrogen, and improve soil organic matter content as well as provide emergency forage. At this time many different species can still be planted. We encourage you to check out the Northeast Cover Crops Council Species Selector Tool that can help you determine the best species for your specific location based on plant hardiness zone, soil type, crop rotation, and goals. The tool also provides information on growth traits, planting and termination information, cost, and additional helpful comments. Below are a couple of species options for fall establishment from the Penn State Agronomy Guide. When creating a mixture of different species, it is recommended to combine species that complement each other. We do not include warm-season annuals because it is already getting late to expect much growth out of them.

Table 1. Recommended latest fall seeding dates for cool-season annual cover crops by small grain management areas in Pennsylvania.

Species Area 1 Area 2 Area 3
Winter rye October 10 October 15 October 25
Winter wheat October 1 October 5 October 15
Winter barley n/a September 25 October 1
Spring oats September 1 September 10 September 15
Annual ryegrass August 15 September 1 September 15
Crimson clover n/a September 1 September 15
Austrian winter pea n/a August 25 August 30
Hairy vetch August 15 September 1 September 15
Forage radish September 1 September 7 September 15
Rapeseed/canola September 1 September 7 September 15
Turnip September 1 September 7 September 15

Source: Penn State Agronomy Guide

Small grain management areas in Pennsylvania (Figure 1.7-1 of The Penn State Agronomy Guide)

Source: Penn State Agronomy Guide

Make sure to consider potential herbicide residual issues, pest life cycles, termination strategies and timing, and cost when choosing a cover crop species or mixture.

Taking advantage of cover crops can add diversity to your crop rotation, help hold or fix nitrogen for your next crop, suppress weeds, protect soil, provide pollinators or livestock food, and more. If you would like assistance navigating the Selection Tool or would like to talk through your cover cropping plan, reach out to your local Agronomy Educator, NRCS Conservationist, or Conservation District Ag Specialist.