Feb., 1925] PROGRESS OF AGRICULTURAL EXPERIMENTS 



17 



1. Comparison of power sprayer and power duster. No early or late-blight 

 developed in the plots, and the plants in the sprayed, dusted and non-sprayed 

 sections went through the season in good condition without significant differ- 

 ence in yields per acre.. 



2. Comparison of power sprayer, hand sprayer and hand duster. No early 

 or late-blight developed in the plots, and none of the methods of treatment had 

 any significant effect on yield. 



3. Effect of number of nozzles and pressure on control of late-blight. In 

 this experiment a triple-action pump was used, and four apphcations of an 

 8-4-50 Bordeaux mixture were given to each plot. Late-bUght appeared late 

 in the season, and frost killed the plants before the non-sprayed rows had been 

 seriously damaged. The results secxrred indicate that if a sprayer api^lies the 

 mixture under 90 pounds pressure better protection is obtained by going over 

 the row twice — back and forth — than by using three nozzles and going over the 

 row once; 180 pounds pressure, all things equal, gives better protection than 90 

 pounds pressure, and 90 poimds pressure going over a row twice is not so good as 

 180 pounds pressure one appUcation; going over the row twice greatly increases 

 the protection afforded, but the expense is not warranted if the sprayer will 

 carry three nozzles per row and apply the mixture under 180 pounds pressure. 



Potato Seed Experiments. 



1. Comparison of some New Hampshire certified seed with seed from other 

 sources. In this experiment seed from New Brunswick was used by Dr. 

 Butler as the comparison strain, the other stocks being grown in alternate rows 

 with it. In Table VI the yield given for the New Brunswick seed is the mean 

 of all the rows, and the yields for the other stocks are relative thereto. A con- 

 sideration of the table will show that all stocks used were very free from degen- 

 eration diseases and that the New Hampslure certified seed was in no way 

 inferior to that from Maine and New Brunswick. 



Table VI. — Percentage leaf-roll and mosaic in and productivity of some New Hampshire and 



other seed. 



2. Effect of using small cut seed-potatoes about 2 ounces in weight — and large 

 cut seed-potatoes 2 ounces to 12 ounces in weight — on yield. The seed used in 

 the experiments was certified Irish Cobbler and Green Mountain. The large 

 seed was cut into chunky pieces and the small seed by bisecting along the major 

 axis. The results obtained were as follows: 



