303 STATE BOARD OF AGRICTJLTURiE 



compared to seed formerly used. There is usually used in Michigau 

 at least three and one-half million bushels of seed each year for planting, 

 indicating that less than 2% of the seed planted is from certified or 

 selected seed stock. The state average yield for ten j-ears is only ninety 

 bushels per aere. An increase of 41 bushels per acre would mean a 

 state average of 131 bushels per acre providing good seed was used by 

 all. A total of 01,168 bushels of certified seed would plant 6,417 acres 

 yielding 840,627 bushels of good seed capable of j)lanting 84,063 acres 

 in 1923 of 24% of the state acreage. 



SPRAYING 



Spraying demonstrations were conducted in 56 counties, seven counties 

 had 21 organized spray rings, containing a memibership of 94 farmers 

 and 64 high pressure (175 lb. -200 lb.) sprayers were introduced by 

 County Agents for controlling insect and foliage diseases. Thirty-two 

 farms, reporting spraying tests with checks, show an average increase 

 in yield of the sprayed over the unsprayed of 57 bushels per acre at a 

 total cost of 19.48 per acre for an average of live sprays. This cost in- 

 cludes cost of materials, labor, de])reciation, interest, etc. The require- 

 ment of the Michigan Potato Producers' Association, that all parties 

 applying for inspection must spray effectively, has resulted largely in 

 establishing the practice. Every farmer reporting that sprayed for the 

 first time this 3^ear, is converted to spraying. 



FERTILIZATION 



Fertilizer demonstrations to increase quality yield, and net return 

 per acre were held in 12 counties. The standard demonstration included 

 a high test fertilizer containing a high percentage of Potash and Acid 

 Phosphate. Ten counties had 25 planned demonstration plats, show- 

 ing an average increase in yield, in the fertilizer over the unfertilized 

 plats of 45 bushels per acre. An average application of 400 lbs. of 

 fertilizer was used on the majority of plots. 



HILL SELECTION 



The practice of hill selection of potatoes at digging time is of special 

 importance to the interested and experienced -potato grower. Two 

 farmers report results of last year's selection as follows : 



A one acre seed plat planted with hill selected seed yielded 432 bushels 

 per acre. Ten acres in balance of field, planted with field run seed, 

 yielded 290 bushels per acre. Another report gave 190 bushels per acre 

 from hill selected seed and 114 bushels per acre from field run seed stock. 



STRAIN TESTS 



A strain te.st of seed from one source distributed to 50 different famis 

 in 16 different counties gave very interesting results. The yields have 

 varied from a high point of 325 bushels per acre to a' low point of 155 

 bushels per aere with an average of 238 bushels per acre for all. The 

 range of 170 bushels per acre in yield is due to spraying, favorable soil 



