The big take-away is that there's mounting evidence against the oft-voiced concern that cover crops steal moisture—and therefore yield—from the following cash crop. In fact, during the drought year of 2012, those who had used cover crops previously reported eye-popping yield boosts of around 10%, most likely because of increased soil water holding capacity. The preliminary data mentioned in the Corn & Soybean Digest piece suggest that, in a more typical year like we saw in the 2013 season, yield bumps for the follow-on cash crop are likely to still be very substantial (around 5%).
The full report is expected out by the summer (see the SARE site for more details).
Themes from 2012-13 survey
- the most common use is following corn and before soy
- establishing the crop was the biggest challenge for growers
- top reasons for using cover crops include reducing soil compaction and erosion, promoting nitrogen scavenging (thus preventing runoff of excess N), and weed control
- yield improvements of about 10% for corn following cover crops in the drought year of 2012, highlighting the likely role for improved water holding capacity
- growers who had used cover crops for more years saw the highest yield bumps.
Expected themes from forthcoming 2013-14 survey
- in a more typical moisture year like 2013, yield gains for corn of about 5% after using cover crops
- big increase in acres seeded with cover crops
- a concern about soil health appears to be driving growers to use cover crops
- a majority of growers planted cover crops even though they were not receiving cost share payments