344 



STATE BOARD OF AGRICULTURE. 



a maximum crop for both varieties. Plantings up till the 10th of June gave 

 a fair crop and were sufficiently mature to store over winter. Plantings 

 made the last two weeks of June gave small jaelds and immature potatoes. 

 Fall plowing is a very desirable practice in potato culture in the north, as it 

 allows for proper fitting of the seed bed for early spring planting. 



Green-Sprouting vs. Unsprouted: — The experimental evidence indicates 

 that green-sprouting is a very desirable practice when for any reason it is 

 found impossible to plant as early as desired. Green-sprouted potatoes 

 will, when planted on the same date as unsprouted, give a crop that will ma- 

 ture from a week to ten days earlier than unsprouted stock. Spreading the 

 potatoes out in diffused sunlight to sprout also allows the grower to discard 

 any tubers which tend to produce weak sprouts, thus allowdng for the se- 

 lection of only good viable seed stock. It also aids in discovering varietal 

 mixtures. 



Cultivating: — The experimental evidence of two years work indicates: 

 The usual method of cultivating deep when plants are small and gradually 

 working to shallow as season advances, is the better one. The harrowing 

 of potatoes before plants are up aids in control of weeds, but does not in- 

 crease the yield. The flat culture on well drained potato soils increases the 

 yield over hilling providing the seasonal rainfall is not above normal. 



Fertilizer Tests: — In 1919 Acid Phosphate was applied broadcast and 

 harrowed in at the rate of 250 and 500 pounds per acre. An apparent gain 

 was noticeable for the first 250 pounds. The fertiUzer tests in 1920 were 

 conducted in cooperation vnih the National Soils Committee. A 3-10-4 fer- 

 filizer was used at varying rates from 500 to 1,500 pounds per acre, applied 

 in the row vnth a fertihzer attachment to the planter. The fertilizer plats 

 all gave an increase in yield over unfertilized plats, though no benefit was 

 apparent by increasing the rate of application above 500 pounds per acre. 



Fig. No. 17. Idaho Rurals (the center three rows) in 1919 were the first to succumb to leaf hopper 

 attaclc. Russet Burbanlcs on the left and Rural New Yorkers on the right remained green through- 

 out the season. 



VARIETY TESTING. 



Several varieties were tested as to their adaptability to produce under the 

 environment of this section. Two important factors influenced potato 

 production in 1919: dry weather and an unprecedented attack of leaf hop- 



