Skip to main content
ARS Home » Research » Publications at this Location » Publication #314250
Title: Stover removal affects no-till irrigated corn yields, soil C and N

Author
item HALVORSON, ARDELL - Retired ARS Employee
item Stewart, Catherine

Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/13/2015
Publication Date: 4/13/2015
Publication URL: http://doi:10.2134/agronj15.0074
Citation: Halvorson, A.D., Stewart, C.E. 2015. Stover removal affects no-till irrigated corn yields, soil C and N. Agronomy Journal. 107:1504–1512.

Interpretive Summary: Corn (Zea mays L.) stover removal can increase yields under no-till (NT) in climates where cold spring soil temperatures delay emergence and plant growth. Partial stover removal (PR) effects on continuous corn grain and stover yields, N uptake, and changes in soil organic C (SOC) and total soil N (TSN) compared to full stover retained (FR) under irrigated NT was evaluated over four N treatments for 7 yr on a clay loam soil. Stover removal (average 66%) increased early spring soil temperatures and enhanced early plant development compared to FR. Grain and stover yields increased with increasing N rate, as did plant N and C uptake, but varied with residue treatment. Averaged over N rate, grain yields were greater with PR than FR, but stover yields were lower with PR than FR. The C:N ratio of stover declined with increasing N rate. Nitrogen fertilization did not significantly influence SOC and TSN stocks after 7 yr. Averaged over N rates, PR removal decreased SOC 3.1 Mg SOC ha-1, but FR increased SOC 7.9 Mg SOC ha-1 in 0-30 cm soil depth. TSN stocks increased significantly with FR (1227 kg N ha-1) but not with PR (7 kg N ha-1). These results suggest that continued, long-term residue removal will negate any initial yield benefits from more rapid early spring plant development. Partial stover removal as a cellulosic feedstock at the levels we used for ethanol production would negatively impact soil quality under irrigated, NT corn production in Colorado.

Technical Abstract: Corn (Zea mays L.) stover removal can increase yields under no-till (NT) in climates where cold spring soil temperatures delay emergence and plant growth. Partial stover removal (PR) effects on continuous corn grain and stover yields, N uptake, and changes in soil organic C (SOC) and total soil N (TSN) compared to full stover retained (FR) under irrigated NT was evaluated over four N treatments for 7 yr on a clay loam soil. Stover removal (average 66%) increased early spring soil temperatures and enhanced early plant development compared to FR. Grain and stover yields increased with increasing N rate, as did plant N and C uptake, but varied with residue treatment. Averaged over N rate, grain yields were greater with PR than FR, but stover yields were lower with PR than FR. The C:N ratio of stover declined with increasing N rate. Nitrogen fertilization did not significantly influence SOC and TSN stocks after 7 yr. Averaged over N rates, PR removal decreased SOC 3.1 Mg SOC ha-1, but FR increased SOC 7.9 Mg SOC ha-1 in 0-30 cm soil depth. TSN stocks increased significantly with FR (1227 kg N ha-1) but not with PR (7 kg N ha-1). These results suggest that continued, long-term residue removal will negate any initial yield benefits from more rapid early spring plant development. Partial stover removal as a cellulosic feedstock at the levels we used for ethanol production would negatively impact soil quality under irrigated, NT corn production in Colorado.