Corn (Zea mays L.) stover was identified as an important feedstock for cellulosic bioenergy production because of the extensive area upon which the crop is already grown. This report summarizes 239 site-years of field research examining effects of zero, moderate, and high stover removal rates at 36 sites in seven different states. Grain and stover yields from all sites as well as N, P, and K removal from 28 sites are summarized for nine longitude and six latitude bands, two tillage practices (conventional vs no tillage), two stover-harvest methods (machine vs calculated), and two crop rotations {continuous corn (maize) vs corn/soybean [Glycine max (L.) Merr.]}. Mean grain yields ranged from 5.0 to 12.0 Mg ha−1 (80 to 192 bu ac−1). Harvesting an average of 3.9 or 7.2 Mg ha−1(1.7 or 3.2 tons ac−1) of the corn stover resulted in a slight increase in grain yield at 57 and 51 % of the sites, respectively. Average no-till grain yields were significantly lower than with conventional tillage when stover was not harvested, but not when it was collected. Plant samples collected between physiological maturity and combine harvest showed that compared to not harvesting stover, N, P, and K removal was increased by 24, 2.7, and 31 kg ha−1, respectively, with moderate (3.9 Mg ha−1) harvest and by 47, 5.5, and 62 kg ha−1, respectively, with high (7.2 Mg ha−1) removal. This data will be useful for verifying simulation models and available corn stover feedstock projections, but is too variable for planning site-specific stover harvest. Abstract Corn (Zea mays L.) stover was identified as an important feedstock for cellulosic bioenergy production because of the extensive area upon which the crop is already grown. This report summarizes 239 site-years of field research examining effects of zero, moderate, and high stover removal rates at 36 sites in seven different states. Grain and stover yields from all sites as well as N, P, and K removal from 28 sites are summarized for nine longitude and six latitude bands, two tillage practices (conventional vs no tillage), two stoverharvest methods (machine vs calculated), and two crop rotations {continuous corn (maize) vs corn/soybean [Glycine max (L.) Merr.]}. Mean grain yields ranged from 5.0 to 12.0 Mg ha −1 (80 to 192 bu ac −1 ). Harvesting an average of 3.9 or 7.2 Mg ha −1 (1.7 or 3.2 tons ac −1 ) of the corn stover resulted in a slight increase in grain yield at 57 and 51 % of the sites, respectively. Average no-till grain yields were significantly lower than with conventional tillage when stover was not harvested, but not when it was collected. Plant samples ( ) 7:528-539 DOI 10.1007 collected between physiological maturity and combine harvest showed that compared to not harvesting stover, N, P, and K removal was increased by 24, 2.7, and 31 kg ha −1 , respectively, with moderate (3.9 Mg ha −1 ) harvest and by 47, 5.5, and 62 kg ha −1 , respectively, with high (7.2 Mg ha −1 ) removal. This data will be useful for verifying simulation models and available corn stover feedstoc...

Core Ideas Cover crops were successfully established in corn with a drill interseeder.Cover crop biomass production varied notably across the mid‐Atlantic region.Spring cover crop biomass was often proportional to fall cover crop performance.Interseeding cover crops at corn growth stages V2–V3 decreased corn grain yields.Interseeding cover crops at or after corn V4 did not affect corn grain yield. Cover crop adoption remains low in the mid‐Atlantic United States despite potential conservation and production benefits. The short growing season window after corn (Zea mays L.) is a primary limiting factor. A high‐clearance grain drill was recently developed to allow for cover crop interseeding into standing cash crops. Experiment 1 tested the viability of drill interseeding cover crops into corn at the V5 growth stage across multiple locations. Experiment 2 tested interseeding timing (V2–V6 corn growth stage) on corn yield in Pennsylvania. At 16 locations throughout Maryland, Pennsylvania, and New York, we evaluated cover crop fall and spring biomass and the effect on corn yield. Cover crop treatments included annual ryegrass [Lolium perenne L. ssp. multiflorum (Lam.) Husnot]), a mixture of legume species, and an annual ryegrass–legume mixture. Each cover crop treatment successfully established across locations yet was highly variable. Across locations, annual ryegrass–legume mixture produced the highest mean aboveground biomass in fall and spring. Spring biomass of interseeded cover crops generally increased compared with fall biomass. Interseeded cover crops did not affect grain yields of the host corn crop during the year of establishment across locations. Experiment 2 indicated that cover crops interseeded before the V3 growth stage reduced corn grain yields. We recommend interseeding at or after V4 to prevent competition with corn. Our results highlight the viability of drill‐interseeding as a strategy for increasing cover crop adoption.

Harvesting feedstock for biofuel production must not degrade soil, water, or air resources. Our objective is to provide an overview of field research being conducted to quantify effects of harvesting corn (Zea mays L.) stover as a bioenergy feedstock. Coordinated field studies are being conducted near Ames,

Three levels of weed control (0, 70, and 100%) were maintained in 1989 during corn production at two sites. Weed control in 1990 with a premix formulation of metolachlor and atrazine was directly related to 1989 control levels. Herbicides generally were more effective in conventional tillage than in no-tillage. In no-tillage, giant foxtail control in 1990 averaged 59% following 100% control in 1989 compared to 15% following 0% weed control. At one location, tillage minimized the impact of the prior year's weed control with herbicides providing greater than 85% control in conventional tillage regardless of prior history. In no-tillage, weed control of 85% or better was obtained only following 100% control the previous year.

The livestock industries are a major contributor to the economy of the northeastern United States. Climate models predict increased average maximum temperatures, days with temperatures exceeding 25°C, and higher annual precipitation in the Northeast. These environmental changes combined with increased atmospheric CO 2 concentration are expected to either increase or decrease forage productivity depending on the crop, and may decrease protein content and forage digestibility. Winter damage to sensitive forage species may also increase. Predicted temperature increases are expected to reduce fertility in dairy cattle and heat stress-induced inflammation may limit energy available for productive functions.