By Glen Arnold
The 2015 growing season was the 2nd year for a corn post-emergent drag hose study at the OARDC Northwest branch at Holtville. The purpose of this plot is to determine how far along in development the corn crop can be before the damage from a drag hose would rule out sidedressing emerged corn with livestock manure. A 15 foot long drag hose filled with water was used for this study.
The six-inch diameter drag hose was pulled across each plot twice (going in opposite directions) at corn vegetative growth stages one through five (stage five was not completed in 2015 due to excessive rainfall). The tractor speed was approximately 4 miles per hour. The plot was replicated four times in a randomized block design.
The 2014 plot experienced an unusually dry growing season, especially in the weeks following the drag hose treatments. Total precipitation received by this plot from planting until October 1st was 11.62 inches. The 2015 plot experienced an unusually wet growing season, especially in the weeks during the drag hose treatments. Total precipitation received by this plot from planting until October 1st was 22.12 inches.
Corn stage | Population 2014 | Yield bu/ac 2014 | Population 2015 | Yield bu/ac 2015 | 2-year average Bu/ac |
No drag hose | 30,166 | 145.1 | 31,850 | 167.2 | 156.2 |
V1 | 29,660 | 154.3 | 31,750 | 166.1 | 160.2 |
V2 | 30,166 | 157.9 | 32,000 | 153.3 | 155.6 |
V3 | 28,933 | 153.9 | 31,375 | 172.3 | 163.1 |
V4 | 29,264 | 149.7 | 23,500 | 123.5 | 136.7 |
V5 | 15,366 | 109.8 | ------- | --------- | ------- |
The results of this two-year research study suggests corn could be sidedressed with liquid livestock manure, using a drag hose, up to growth stage three (three leaf collars) without a statistically significant yield loss. This study will be repeated in next three seasons to establish a five-year data base.