Cover Crops and Conservation Tillage for Soil Erosion Control on Cropland

Table of Contents

Reduce Surface Water Pollution — Benefits of Cover Crops

Due to the almost total elimination of surface water runoff from the continuous presence of ground covers, the loss of nutrients and pesticides by this route is almost eliminated (See Table 1).

Table 1. Average water, soil and cyanazine^a (Bladex) runoff losses from a 14% slope planted to conventional and no-till corn with and without a birdsfoot trefoil or crownvetch living mulch from May through October for 3 growing seasons (1977-79). Hall et al. (1984)

	CTb	NT-CSM	NT-BFT	NT-CV
Cyanazine pre emergence @ 2.0 lb a.i./A on CT, 4.0 lb a.i./A on NT. CT = conventional tillage-rototilled, NT-CSM = no-till in corn stover mulch, NT-BFT = no-till in CSM + birdsfoot trefoil living mulch, NT-CV = no-till in CSM + crownvetch living mulch. Data collected from seeding to harvest of corn. Reduction relative to the CT cropping system which received half the cyanazine rate.
Water run off (gal/A)	61,000 c	6,270 (90%)d	2,670 (96%)	2,000 (97%)
Eroded soil (lb/A)	12,690	375 (97%)	50 (99.6%)	18 (99.9%)
Cyanazine loss in runoff water (% of appl.)	2.4	0.31 (87%)	0.12 (95%)	0.12 (95%)
Cyanazine loss in sediment (% of applied)	0.2	0.01 (95%)	0.0 (100%)	0.0 (100%)
Total cyanazine loss (%)	2.6	0.32 (88%)	0.12 (95%)	0.12 (95%)