control program, damage in com- 

 mercial producing areas would 

 greatly exceed that now being ex- 

 perienced. 



CONTROL METHODS 



Growers can prevent or greatly 

 reduce weevil infestation by follow- 

 ing the procedures outlined below. 



Seed 



Plant weevil-free seed. If possible, 

 obtain seed from an uninfested area. 

 If you cannot do this, examine care- 

 fully each sweetpotato chosen for 

 seed: reject any that are weevil 

 infested. 



Store seed apart from other sweet- 

 potatoes. Place seed in storage one 

 layer at a time and cover each layer 

 with 10-percent DDT dust. Use 1 

 pound of dust for each 6 to 8 bushels 

 of seed. 



Storage Places 



Empty, clean, and treat all storage 

 places in the spring at least a month 

 before the new crop is planted in 

 the field. 



Treat storage places thoroughly 

 with DDT dust or spray. Apply 1 

 pound of 10-percent DDT dust for 

 each 1,600 square feet. Or apply 

 DDT spray (made by mixing 8 

 pounds of 50-percent wettable pow- 

 der in 100 gallons of water) at the 

 rate of \ l / 2 gallons per 1,000 square 

 feet. 



Plant Bed 



Maintain a visible covering of in- 

 secticide dust on the plant beds from 

 the time the stems of the first plants 

 begin to show color until the beds 

 have been destroyed. 



Use 2-percent dieldrin or 2- to 2 l / 2 - 



6 



percent heptachlor dust (nongran- 

 ular). Apply with an ordinary 

 garden-type rotary duster, a bellows- 

 type duster, or any other equipment 

 that will distribute the dust and 

 leave it in the proper position. 



Make two or more applications as 

 follows: 



First application : When first 

 plants begin to show color, apply 

 dust on and around base of all plants 

 that are up. 



Second application: When all 

 plants are up, apply dust to cover the 

 soil next to all plants. 



Other applications : After all 

 plants are pulled, apply dust if it is 

 needed to keep the soil covered. If 

 plants are allowed to run to produce 

 vine cuttings, dust at the time vines 

 drop to the ground and start to run. 



Planting in the Field 



Plant sweetpotatoes in fields where 

 sweetpotatoes have not been grown 

 the season before. In preparing the 

 soil, give the roots enough loose 

 earth in which to develop; they 

 should not become exposed above- 

 ground. If possible, use sweetpotato 

 varieties that tend to develop deep 

 beneath the surface. Plant cuttings 

 instead of rooted plants whenever 

 this is practicable. 



After Planting 



Apply 2-percent dieldrin or 2- to 

 2 ^-percent heptachlor dust (non- 

 granular) to sweetpotatoes in the 

 field. Make one heavy application 

 to sweetpotatoes of deep-rooted va- 

 rieties such as Porto Rico. Make 

 two lighter applications to those 

 of shallow-rooted varieties such as 

 Goldrush. 



For deep-rooted varieties, apply 



