Cover Crops and Conservation Tillage for Soil Erosion Control on Cropland

Table of Contents

Table 3. Herbicide effectiveness on common weeds for establishing crownvetch in corn.¹
Cover Crops Treatment number from Table 9-2
1, 3, 7 2 4 5² 6² 8 9
¹ 10 = 95–100%, 9 = 85–95%, 8 = 70–85%, 7 = 65–75%, 6 = 55–65%, 5 = less than 55%, N = No control, ? = unknown, - not present. Above ratings are for average conditions; results may differ with variations in weed size, temperature, rainfall, soil moisture, soil type, and soil pH.
² Effectiveness on emerged weeds only; no residual weed control from paraquat, Roundup Ultra, or Touchdown alone.
* Top kill only.
Crownvetch 5 5 5 - - N 5
Birdsfoot trefoil 6 5 6 - - 6 7
Summer annuals
Barnyardgrass 8 8 8 10 10 7 8+
Black medic ? ? ? 9 10 ? ?
Buckwheat, wild ? ? ? 10 9 ? ?
Burcucumber 7 6 6 9 9 ? 7
Chamomile, mayweed ? ? ? 9 10 ? ?
Cocklebur, common 8 8 8+ 10 10 9+ 7
Crabgrass, large or smooth 8 7 9 9 10 9 6
Foxtail, giant 9 8 8 9 10 8 9
Foxtail, green 9 8 8 10 10 8+ 9
Foxtail, yellow 9 8 8 10 10 8+ 9
Galinsoga, hairy 9 9 9 10 10 ? ?
Goosegrass 9 6 9 9 10 9 ?
Jimsonweed 8 8 8+ 10 10 6 7
Johnsongrass (seedling) 7 8 8 - 10 7+ 9+
Ladysthumb 9 9 9 10 10 ? 8
Lambsquarters, common 10 7+ 8 10 10 9 6
Lambsquarters, common TR 10 7+ 8 10 10 9 6
Morningglory, ivyleaf 7 5 5 10 10 7 7
Morningglory, tall 7 5 5 10 10 7 7
Mustard, wild 9+ 9 9 10 10 ? ?
Nightshade, eastern black 8 8 8 10 10 N ?
Panicum, fall 9 7 9 9 10 5 9
Pigweed, redroot 10 9+ 9+ 10 10 9+ 9
Pigweed, smooth TR 9+ 9+ 9+ 10 10 9 9
Purslane, common 9 9 9 10 10 ? ?
Radish, wild 8 8 8 9 10 ? ?
Ragweed, common 7 7+ 7 10 10 5 5
Ragweed, giant 5 5 5 9 10 N N
Shattercane 8+ 8 8 9 10 8+ 9+
Smartweed, Pennsylvania 9 8+ 8+ 10 10 8 8
Velvetleaf 9 8+ 8+ 10 10 8+ 7
Witchgrass 9 7 9 9 10 9 9
Biennials
Burdock, common N N N 9* 8 N N
Carrot, wild N N N 9* 9 N ?
Fleabane, rough ? ? ? 9* 9 N ?
Parsnip, wild N N N 9* 9 N ?
Rocket, yellow       9* 9 ? ?
Thistle, plumeless N N N 9* 9 N ?
Perennials
Bedstraw, smooth N N N 9* 9 N ?
Bindweed, field N N N 9* 8+ N ?
Bindweed, hedge N N N 9* 8+ N ?
Blackberry N N N 9* 8 N ?
Chamomile, corn N N N 9* 9 N ?
Chickweed, mouseear N N N 9* 9 N N
Cinquefoil, sulfur N N N 9* 9 N ?
Cockle, white N N N 9* 8+ N ?
Dandelion N N N 9* 6 N ?
Dewberry, northern N N N 9* 7 N 8
Dock, broadleaf and curly 5 N N 9* 8 N ?
Dogbane, hemp N N N 9* 7 N 7+
Garlic, wild N N N 8* 7 N ?
Goldenrod N N N 9* 8 N ?
Groundcherry N N N 9* 8 N ?
Horsenettle N N N 9* 7 N ?
Johnsongrass (established) 7 6 6 9* 9 N 9
Milkweed, common N N N 9* 5 N ?
Nutsedge, yellow 7 7 8 9* 9 N 6
Plantains 5 N N 9* 8 N ?
Poison ivy N N N 9* 7 N ?
Pokeweed, common N N N 8* 8 N ?
Quackgrass 8 N N 9* 8 N 9
Rocket, yellow 9 ? 9 9* 9 N ?
Sorrel, red N N N 9* 8 N ?
Thistle, Canada N N N 9* 7 N 5
Wirestem muhly 6 N N 9* 9 N 7