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CONTROLLING WEEDS IN STRAWBERRIES WITH HERBICIDES 



Dominic A. Marini 

 Regional Fruit and Vegetable Specialist 



Since strawberries occupy the soil for more than a year from 

 planting to harvest, control of weeds is a major production prob- 

 lem. Herbicides, properly used, can reduce the problem consider- 

 ably but not entirely. Some cultivation is necessary for loosen- 

 ing the soil to enhance the rooting of runners, and to eliminate 

 weeds not controlled by herbicides. 



In Massachusetts, herbicides that have been found effective 

 for use on strawberries are chloroxuron fNorex* or Tenoran*) , Dac- 

 thal* and diphenamid (Dymid* or Enide*). Dacthal* and diphenamid are 

 pre-emergence materials and must be applied to weed-free soil before 

 weeds appear; they do not control weeds that have emerged. Chlorox- 

 uron can be applied either pre-emergence or early post-emergence be- 

 fore weeds reach two inches in height. Best results are obtained 

 when herbicides are uniformly applied to moist, smooth, clod-free 

 soil followed by one-half to one inch of rain or irrigation within 

 one week. 



Dacthal* may be pre-plant incorporated -- apply and work it in- 

 to the soil shallowly with a disc harrow or weeder before setting 

 plants. Or, it may be applied immediately after transplanting. It 

 is effective for about 6 weeks and controls annual grasses and most 

 broadleaf weeds except ragweed, smartweed and Galinsoga. It may 

 also be applied late in the season for fall and winter weeds. 



Diphenamid should not be applied on new beds until plants are 

 established, and it may not be applied again for 6 months. It is 

 effective for about 8 weeks and controls annual grasses and broad- 

 leaf weeds except Galinsoga. It is not recommended for use on the 

 Raritan variety since injury may occur. 



Chloroxuron should not be applied until plants are established 

 and not more than twice in one season. It is effective for about 

 8 weeks. Most broadleaf weeds are controlled up to two inches tall, 

 while Galinsoga is controlled up to 3/4 of an inch in height. Grass 

 control is poor, particularly with post-emergence applications. 

 Do not apply it when temperature exceeds 85°F, as injury may occur. 

 Late season applications control fall, and winter weeds. 



Some growers apply Dacthal* at transplanting followed by an 

 application of chloroxuron when weeds begin to appear for long term 

 weed control. 



*Trade name 



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