RHUBARB


Weed Problem   Chemical   Pounds Active Ingredient (AI)/Acre   Amount of Commercial Product/Acre   Remarks and Limitations

Emerged weeds before crop emergence   paraquat
(GRAMOXONE SL 2.0)
  0.5-1.0  
2-4 pt
  Apply to dormant rhubarb. Use higher rate for heavier weed infestation. Do not exceed 2 applications per season. Include 1 pt NIS/100 gal. RUP.

Preemergence   diclobenil
(CASORON 4G)
  2  
50 lb
  Apply before rhubarb emerges in early spring. Must be watered into soil.

  halosulfuron
(SANDEA 75 WDG)
  0.023 - 0.047  
0.5 - 1 oz
  Apply to dormant rhubarb in the spring. Sandea may cause crop stunting. Use low rate to determine crop safety under field conditions. 60 day PHI. Controls yellow nutsedge. No grass control.

  linuron
(LOROX 50DF)
  1-1.5  
2-3 lb
  Broadcast to dormant rhubarb in the spring before leaves emerge.

  mesotrione
(CALLISTO 4SC)
  0.188  
6 fl oz
  Apply to soil before rhubarb breaks dormancy in the spring. Application after growth begins will cause crop stunting and bleaching. 21 day PHI.

  prometryn
(CAPAROL 4L)
  1-2  
2-4 pt
  Apply to dormant rhubarb before leaves emerge in spring. Use low rate on light soil. 40 day PHI.

  pronamide
(KERB 3.3SC)
  1-2  
2.5-5 pt
  Apply to dormant plants after frost has killed leaves in fall. Suppresses quackgrass. Do not apply to rhubarb the year of planting. Include glyphosate with application for better weed control. 38 day PHI. RUP. SLN label.

  s-metolachlor
(DUAL MAGNUM 7.62EC)
  0.63-1.26  
0.67-1.33 pt
  Apply in spring before rhubarb and weeds emerge. Make a second application after harvest. Do not exceed 1.33 pt/acre/year. 62-day PHI.

Postemergence   quinclorac
(QUINSTAR 4L)
  0.37  
12.6 fl oz
  Apply as a foliar spray to control Canada thistle, field bindweed. A 2nd application may be made 30 days after the first. Max. 25.2 fl oz/acre/yr. 30 day PHI.

Postemergence grasses   clethodim
(SELECT MAX 0.97E)
  0.068-0.12  
9-16 fl oz
  Include 0.25% NIS/acre in spray mix. Maximum 64 fl oz/acre/year. 30-day PHI.

  sethoxydim
(POAST 1.5E)
  0.19-0.28  
1-1.5 pt
  Apply to actively growing grasses. Include 1 qt COC/acre. 15-day PHI.

Perennials   glyphosate
(ROUNDUP 4L)
  2-3  
2-3 qt
  Apply to dormant rhubarb to kill emerged weeds in spring or fall. Do not apply over row if rhubarb has emerged in spring.