Weed Control

Herbicide choice

Propyzamide (Kerb) at up to 840 g ha-1 provides additional grass weed control including wild oats and sterile brome plus some broad leaved weeds. Carbetamide (Crawler) is applied pre- or early post-emergence of weeds from November to the end of February. It controls annual meadow-grass, black-grass and barren brome (pre- and post-) and gives some control of volunteer cereals and wild oats post-emergence. It only controls a few broad-leaved weeds, including speedwells (pre- and post-) and cleavers and knotgrass (pre). It can be used on all soil types except soils with more than 10% organic matter.

01

Figure 3. Control of resistant
blackgrass in winter beans.
c. Cook et.al., 1991.
Aspect Applied Biology (27)
Production and protection
of legumes p. 161-6.

Cleavers can be a difficult weed to control in many break crops. Clomazone present in both Centium 360 CS and Lingo (clomazone + linuron) plus an off-label approval for prosulfocarb (Defy) provide control of cleavers plus activity on a range of broad leaved weeds.(Figure 4). Defy also offers activity on grass weeds such as loose silky bent and annual meadow grass. Both are residual herbicide for pre emergence use only and can be used on most soil types but clomazone cannot be used on those containing more than 10% organic matter and very light soils and sands. They require good seedbed conditions. Other herbicide possibilities are listed below in Table 1.

Several pendimethalin products have off-label approval for use at 1320gai/ha in winter beans.

Nirvana (imazamox + pendimethalin) can be used pre-emergence in winter beans and provides wide spectrum residual broad-leaved weed control. It shows excellent activity against polygonums, black-bindweed, redshank and knotgrass. Charlock is also effectively controlled as is chickweed. Nirvana also gives improved control of early emerging volunteer oilseed rape when compared to pendimethalin alone and at higher rates can reduce cleaver numbers effectively.

02

Figure 4. Comparative activity of
various herbicides on cleavers
in winter beans c. FMC, 2001

 

 
OFF-LABEL
 
Nirvana
Defy
Lingo
Black bindweed
S
MR
S
Blackgrass
MR
   
Brome, barren      
Charlock
S
S
S
Chickweed
S
S
S
Cleavers
MR
S
S
Cranesbill  
S
 
Dead nettle, Henbit
S
   
Dead nettle, red
S
 
S
Fat hen
S
MR
S
Forget me not  
S
 
Fumitory
S
S
 
Groundsel
MR
S
S
Hemp nettle      
Knotgrass
S
MR
S
Marigold, corn      
Mayweed
MS
R
 
Meadow grass
S
S
 
Nettle, small
MS
S
S
Nightshade, black
MS
S
S
Oilseed rape
MS
MR
 
Parsley, fools
MR
 
S
Pansy, field
MR
MR
 
Parsley piert  
S
S
Pennycress      
Persicaria, pale  
MR
 
Pimpernel, scarlet
S
 
S
Poppy
S
R
 
Radish, Wild
MS
   
Redshank
S
MR
S
Ryegrass      
Shepherds purse
MR
S
S
Sowthistle, smooth
S
S
S
Speedwell, common
S
S
S
Speedwell, ivy leaved
S
S
 
Spurrey, corn      
Volunteer cereals      
Wild oats      

 

Table 1. Activity of various herbicides on broad leaved and grass weeds in field beans.

Weed species
Clomazone
Pendemethalin
Propyzamide
Tebutryn + terbutylazine
 
Stomp 400 SC
 
Black bindweed  
MS
 
S-MR
S
S
S
Blackgrass
S
   
S
S
 
S
Brome, barren      
S
     
Charlock        
S
S
R
Chickweed
S
S
S
S
S
S
S
Cleavers
S
       
R
R
Cranesbill  
MR
         
Dead nettle, Henbit    
S
     
S
Dead nettle, red  
MS
S
 
S
S
 
Fat hen
S
MS
S
S-MR
S
 
S
Forget me not  
MR
S
       
Fumitory
S
MR
MS
 
S
S
MS
Groundsel  
MS
   
S
S
R
Hemp nettle  
MR
S
 
S
S
S
Knotgrass
S
MS
S
S-MR
 
S
S
Marigold, corn    
S
 
S
 
R
Mayweed  
MR
MS
 
S
S
R
Meadow grass
S
MR
S
S
S
S
S
Nettle, small  
MS
S
S-MR
S
S
 
Nightshade, black  
MS
   
S
 
R
Oilseed rape    
S
   
R
 
Parsley, fools  
S
     
R
R
Pansy, field  
MR
S
   
S
S
Parsley piert    
S
       
Pennycress  
S
       
R
Persicaria, pale  
MS
     
S
S
Pimpernel, scarlet    
S
 
S
 
S
Poppy  
MR
S
 
S
S
MS
Radish, Wild            
R
Redshank  
MS
   
S
 
MS
Ryegrass
S
           
Shepherds purse  
S
MS
 
S
 
R
Sowthistle, smooth  
MS
S
 
S
 
R
Speedwell, common
S
MS
S
S-MR
S
S
S
Speedwell, ivy leaved  
MS
S
S-MR
 
R
S
Spurrey, corn          
S
MS
Volunteer cereals
S
   
S
MS-R
   
Wild oats
S
   
S
MS
 
MS

Contact graminicides also provide good control of grass weeds. ‘Laser’, ‘Pilot’, ‘Fusilade’ and ‘Falcon’ can all be used on beans and provide varying control of most species (Table 2). ‘Aramo’, containing tepraloxydim, has limited scope for dose rate reduction but provides good control of difficult species such as couch and resistant blackgrass (including target site resistance)(Figure 5). ‘Aramo’ should not be used alone for resistant blackgrass as resistance to this group of herbicides develops quickly (within 2 to 3 years of constant lone use) but should be used in sequence with other herbicides, including those mentioned above.

Table 2. Effective dose rates of various contact graminicides for use in broad-leaved crops.

These rates present a guide to the differential susceptibility of specific graminaceous species to each active ingredient and should be used in conjunction with manufacturers recommendations.

 
FALCON
FUSILADE
PILOT
ARAMO
LASER
Full rate
1.5 l ha-1
MAX
0.25/0.5* l h-1
1.5 l ha-1
2.25 l ha-1
3.0 l
+ Actipron 2 l
+ Actipron 0.8%
Volunteer barley
0.15-0.35
0.4
0.06
1
0.5-0.7
Volunteer wheat
0.2-0.35
0.4
0.06
1
0.5-0.7
Blackgrass
0.5-0.7
0.6-0.8
0.2
1
0.7-1.0
Wild Oats
0.4-0.5
0.4
0.15-0.25
0.8
0.4-0.7
Ryegrasses
1 (poor control)
1
0.4
0.8
0.6-0.7
Couch
1.0 (0.7 reasonable)
3
1
1.5
2.25 (followed by 1.0) (Poor)
Annual meadow grass
0.7-1.5
Resistant
Resistant
1.5
Resistant
Sterile brome
0.6
0.6-0.8
0.3
-
0.75-1.0
Creeping bent
n/a
3
0.25/0.5
n/a
2.25
Black bent
n/a
3
0.25/0.5
n/a
1.5-2.0

 

03

Figure 5. Control of resistant
blackgrass with various contact
graminicides [redrawn from data
produced by BASF Ltd, 2000]