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Strawberries 



Sesone (SES) has been recommended for the control of summer weeds in straw- 

 berries for a number of years. If used according to directions, it is a fairly 

 good weed killer and is very unlikely to damage the strawberry plants. This 

 chemical is in an inactive form when applied to the soil. It must be changed to 

 the active form by bacteria before it becomes effective. Furthermore, it is 

 effective against germinating seeds and very small weeds only. After the weed 

 seedlings become 1/4 of an inch tall or more, Sesone is not effective. 



To obtain the best results with Sesone, the field should be thoroughly cul- 

 tivated and hoed to eliminate all weeds i.mmediately before application. Because 

 of the necessity for bacterial action to make Sesone active, the soil should be 

 at a moisture content suitable for a good seed bed. If the soil is very dry and 

 there is no rain for several days, it may be necessary to irrigate in order to 

 make Sesone effective. 



The usual rates of application for Sesone are 2 pouvids per acre on very 

 light soils, 2-1/2 pounds per acre on light soils, 3 pounds per acre on medium 

 soils, and 4 pounds per acre on heavy soils. For small areas, one level teaspoon- 

 ful for 150 square feat equals one pound per acre. 



Since newly set strawberry plants are sensitive to Sesone, it is safest to 

 wait two to three weeks after planting before making the first application. 

 Applications made while runner plants are rooting may cause temporary injury and 

 "delay in the rooting process. When Sesone is used during the bearing year, avoid 

 undesirable residue by not making applications later than one week before picking 

 begins. 



2,4-D was one of the first of the modern weed killers used on strawberries 

 and looked very promising for a time. Hox^ever, it was soon found that it could 

 seriously upset runner growth if applied during the period of runner development. 

 Furthermore, if it is applied during fruit bud formation or at any time when 

 there are flowers or fruit on the plants, the result is small misshapen berries. 

 Therefore, the periods when 2,4-D can be used are quite restricted. Probably its 

 greatest usefulness is in assisting to clean up the bed after the first crop where 

 the bed is to be renovated and a second crop produced. The recommended rate is 

 1 to 1-1/2 pounds of actual 2,4-D acid equivalent per acre. 



Chloro-IPC (GIPC) is useful for the control of fall and winter weeds, par- 

 ticularly chickweed. This is a material which can be extremely helpful if used 

 properly but can do serious harm if not used according to directions. First, it 

 should never be used until the strawberry plants have become dormant. This is 

 usually the middle of November or later. Second, it should never be used in 

 excess of recommended rates. Although it has been cleared for use at rates up to 

 3 pounds per acre, it is felt that under Massachusetts conditions 1 pound per acre 

 is much safer. 



