time within the density ranges sampled. At a labor cost of $2.50 per hour, this would 

 represent a savings of $342 to $387 per acre. For the more effective fumigants, which 

 reduced weeds by over 20 per square foot, the savings in labor were generally over 

 $700 per acre and ranged as high as $1,000 per acre. 



Hand weeding is not, however, the only alternative to weed control. Herbicides, 

 including the aromatic oils, and mechanical cultivation are successfully used at many 

 nurseries to reduce weed populations and minimize hand work. Aromatic oils are 

 successfully used on most species at Savenac, but have never been a dependable weed 

 control measure at Coeur d'Alene without the risk of damage to the conifer crop. As 

 yet, none of the synthetic herbicides has been useful except on non-crop areas such as 

 fence lines and irrigation pipelines. Mechanical cultivation between drill rows has 

 been abandoned because of the danger of soil splash on small seedlings. However, fumi- 

 gation as a weed control measure alone is financially justified at Coeur d'Alene where 

 conditions are characterized by: high residual weed seed population; weeds resistant to 

 selective herbicides; crop species for which there is no suitable selective herbicide; 

 and soil conditions which prevent mechanical cultivation. 



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