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The amount of labor, time and money which it is expedient to 

 spend on the treatment of the insect in strawberry fields depends in 

 a large measure upon its abundance and the past experience of the 

 owner. Each case must be judged on its own merits. In most 

 cases it probably will not pay to treat the insect, but in cases as 

 serious as those referred to from New York it demands considerable 

 attention. When experience shows that treatment is advisable, the 

 following recommendations will be of use. 



Preventives. 



i. Strawberry plants known to be infested should not be in- 

 troduced into uninfested regions, unless it be at a season when 

 the recommendations given under remedies for nursery plants are 

 applicable. 



2. In locating new fields those not adjacent to old infested 

 fields are to be preferred. As the natural spread of this insect is 

 clue largely to winds rather than to its powers of flight the value of 

 thus locating a new strawberry field is obvious. It has been the ex- 

 perience of the writer that the^Aleyrodesoccur in greatest abundance 

 on those fields which are nearest to the old infested ones. 



3. Plants for propagation should be grown for that purpose 

 alone in a nursery isolated from the fruiting beds. This method not 

 only acts as a preventive against the insect but is in accordance 

 with the best methods of strawberry culture. 



4. If plants are chosen from an infested field for setting pur- 

 poses they should be taken, when possible, from the least infested 

 parts of the field. 



5. Plow under the old infested fields as soon as the fruit is 

 harvested. 



Remedies. 



1. In the Nursery. When plants for setting purposes are 

 grown in separate plots or nurseries, they should be first thoroughly 

 treated there, as in such cases the next year's fruiting plants are con- 

 fined to a comparatively small area, and the trouble and expense of 

 treatment is proportionately less. The number of Aleyrodes on such 

 plots can be reduced to a minimum by pinching off and removing in 



