14 MAINE AGRICULTURAL EXPERIMENT STATION. I906. 



inoculated and one not, had less root nodules. So far as known 

 peas had never been grown on this or nearby land. The organ- 

 ism must have been present in the soil or else upon the seed used. 

 The results of these two experiments are not satisfactory 

 because of the exceedingly sharp drouth, but they seem to indi- 

 cate that most soils that have been long cultivated are well 

 stocked with the nodule forming bacteria and that a fertilizer 

 containing only the mineral constituents, or at the most a little 

 added nitrate nitrogen, will supply all the needed plant food for 

 a good crop of peas. 



Sal Bordeaux for Potato Blight. 



In 1904* experiments were made with dry Bordeaux mixture 

 as a preventive of late blight that showed the dry Bordeaux to 

 be inferior as fungicide and preventive to the wet Bordeaux 

 mixture when applied as a fine spray. The Dust Sprayer Man- 

 ufacturing Company of Kansas City, Mo., prepare a fine pow- 

 der that they have named Sal Bordeaux. It consists of equal 

 parts by weight of exceedingly finely ground copper sulphate 

 and lime. This is applied as a dust and the theory is that as 

 soon as this dust becomes moist, from dew or otherwise, the 

 regular Bordeaux mixture in concentrated form is produced at 

 once upon the foliage. 



Five plots of one acre each were used in an experiment on the 

 farm of Mr. John Watson of Houlton in comparing the effect of 

 dusting potato vines with Sal Bordeaux and spraying with regu- 

 lar Bordeaux mixture. The potatoes were all Green Mountain. 

 A high grade fertilizer (Watson's Improved) was used at the 

 rate of 1,250 pounds per acre. The different plots were dusted 

 and sprayed on the same days as follows, July 5, July 15, July 

 25, (followed by showers), August 2, August 10, and August 

 22. 



The Sal Bordeaux was applied at the rate of 10 pounds, 6 

 pounds and 3 pounds per acre. It was diluted with lime in each 

 case and until the danger of bugs was over, Paris Green was 

 iised at the rate of half a pound per acre. On July 31 all the 

 dusted plots were also sprayed with one pound Paris Green anO 

 two pounds of lime per acre, as these plots were pretty badly 

 infested with the potato beetle. Either the dusted poison was 



* Bui. 112, Maine Agricultural Experiment Station p. 6. 



