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  2. Agriculture
  3. Alfalfa
  4. Susceptibility of Weeds to Herbicide Control in Seedling Alfalfa
Agriculture: Alfalfa Pest Management Guidelines

Susceptibility of Weeds to Herbicide Control in Seedling Alfalfa

Weeds Pages

POSTEMERGENCE
  24DB*1 24DB*2 24DB*3 24DB*4 BRO1 BRO2 CLE1 CLE2 GLY+ HEX IMA1 IMA2 IMZ1 IMZ2 PAR* SET1 SET2
Mode of Action 4 4 4 4 6 6 1 1 9 5 2 2 2 2 22 1 1
BROADLEAF WEEDS
Burclover N — N N N N N N P P N N N N N N N
Buttercup N — N N N N N N — — C C P C C N N
Celery, Wild N — N N N N N N C P N N N N P N N
Chickweed N — N N N N N N C P C C C C C N N
Cocklebur C — C C C C N N C C C C C C P N N
Dock, Curly (seedling) P — C C N N N N C N N P N N N N N
Dovefoot N — N P N N N N C — C C C C C N N
Fiddleneck N — N N C C N N P P N P N P P N N
Filarees N — N N N N N N P P P C P C P N N
Fleabane P — — — — — N — C — — — — — — — —
Groundsel, Common N — P C P C N N C C N N N N P N N
Henbit N — N N N N N N C N N P P C N N N
Jimsonweed P — C C C C N N C — C C C C C N N
Knotweed (seedling) N — P C P P N N C C P C P C N N N
Lambsquarters C — C C C C N N C C N N P C C N N
Lettuce, Miners N — N N N N N N C P C C P C C N N
Lettuce, Prickly P — C C P C N N C N N N N N C N N
Mallow, Little (cheeseweed) N — N N N N N N P N P C P C N N N
Milkthistle N — N P N P N N C — N N N N P N N
Mustard, Black N — P C C C N N C P C C C C P N N
Nettle, Burning N — N P N N N N P N P C P C N N N
Nightshade, Hairy P — C C C C N N C C C C C C C N N
Oxtongue, Bristly — — P P P C N N — — N P — — — N N
Pineappleweed N — N N N P N N C P N N N N C N N
Pigweed, Redroot C — C C N P N N C C C C C C N N N
Radish, Wild N — P C N P N N C P P C P C P N N
Rockpurslane, Desert N — N N N N N N C N C C N N C N N
Rocket, London P — C C P C N N C P C C C C C N N
Rush, Toad N — N N — — N N C C C C — — N N N
Shepherd's-Purse N — P P C C N N C P P C C C P N N
Smartweed, Swamp P — C C P C N N C C C C — C P N N
Sowthistle P — C C C C N N C N N N — — C N N
Speedwell, Thymeleaf N — N N N N N N C N N N N N N N N
Spurge, Petty N — N N N — N N — — C C — — C N N
Spurry, Corn N — N N N N N N C C N N — — C N N
Starthistle, Yellow N — N N P C N N — C N N — — C N N
Sunflower, Wild C — C C C C N N C C C C C C P N N
Swinecress N — N P N P N N C C C C — — P N N
Willowherb, Panicle P — C C N — N N — — C C — — N N N
GRASS WEEDS
Barley, Hare N N N N N N C C C N N N C C P C P
Barnyardgrass N N N N N N C C C N C C C C P C C
Bluegrass, Annual N N N N N N P C C P N P N P C N N
Brome, Ripgut N N N N N N C C C N N N C C P P —
Canarygrass, Hood N N N N N N C C C N N P C C P C C
Fescue, Rattail N N N N N N — C C N N N P P P N P
Foxtail, Yellow N N N N N N P C C N N P C C P C C
Goosegrass N N N N N N P P C N N N N N N P P
Oat, Wild N N N N N N C C C N P P C C P C C
Punagrass N N N N N N P C P N N N N N N P C
Ryegrass, Italian N N N N N N C C C/P^ N N N C C C C C
Wheat, Volunteer N N N N N N C C C N N P C C C C C
C= control    P= partial control    N= no control    —= no information
Chemical Legend
24DB*1 = 2,4-DB* (Butyrac 0.5) MOA: 4           HEX = hexazinone (Velpar 0.25) MOA: 5
24DB*2 = 2,4-DB* (Butyrac 0.75) MOA: 4 IMA1 = imazethapyr (Pursuit 0.063) MOA: 2
24DB*3 = 2,4-DB* (Butyrac 1.0) MOA: 4 IMA2 = imazethapyr (Pursuit 0.094) MOA: 2
24DB*4 = 2,4-DB* (Butyrac 1.5) MOA: 4 IMZ1 = imazamox (Raptor 0.031) MOA: 2
BRO1 = bromoxynil (Maestro 0.25) MOA: 6 IMZ2 = imazamox (Raptor 0.047) MOA: 2
BRO2 = bromoxynil (Maestro 0.375) MOA: 6 PAR* = paraquat (Gramoxone) MOA: 22
CLE1 = clethodim (Select Max 0.1) MOA: 1 SET1 = sethoxydim (Poast 0.375) MOA: 1
CLE2 = clethodim (Select Max 0.24) MOA: 1 SET2 = sethoxydim (Poast 0.46) MOA: 1
GLY+ = glyphosate (Roundup WeatherMax) MOA: 9      
* Permit required from county agricultural commissioner for purchase or use.
+ For use in Roundup Ready alfalfa only.
1 Not usually applied at times suitable for controlling winter weeds.
▽ Group numbers are assigned by the Weed Science Society of America (WSSA) according to different modes of action. Although weeds may exhibit multiple resistance across many groups, mode-of-action numbers are useful in planning mixtures or rotations of herbicides with different modes of action.
Text Updated: 04/24
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