310 (STAlTE BOARD OF AGRICULTUiRiE 



ings were held at 179 field demonstrations with an attendance of 3,850 

 people, while 280 farm visits were made where the owner had either 

 ■demonstrations or the field showed something of merit or was strikingly- 

 abnormal. In these field meetings attention was brought to weak or 

 diseased plants that should be removed from the seed plot. The type 

 of plant growth and the shape of the tuber desirable to save for seed 

 purposes was pointed out. 



The Extension Specialist selected hills from farms of the best growers, 

 showing particular vigor, freedom from disease and of good varietal 

 ty^pe. These hills will be taken to the Experiment Station and increased 

 by the Plant Breeder and Plant Pathologist in co-operation with the 

 Extension Specialist. The increase will be selected for type vigor and 

 freedom from disease. 



REPORT OF EXTENSION WORK IN POTATO SEED CERTIFICA- 

 TION AND CULTURAL PROJECTS 



BY H. C. MOORE 



Forty demonstrations were conducted in co-operation with the County 

 Agricultural Agents. These demonstrations showed the value «f seed 

 selection, spraying, seed treatment and the use of common fertilizers 

 in bettering the quality of the potatoes and increasing the yields, 



1,020 acres of potatoes were inspected for certification in 1921 ; 651 

 acres passed the inspection and were certified. Approximately 81,400 

 bushels of certified seed potatoes were sold , at a premium of' approxi- 

 mately 75 cents a bushel over U. S. No. 1 table stock. The inspection 

 and certification work has benefited the potato industry of the state 

 by making available for Michigan growers seed stock of high yielding 

 ■strains, free from varietal mixtures and comparatively free from disease. 

 Furthermore, the good cultural methods followed by growers of cer- 

 tified seed serve as demonstrations to other growers. In 1922, 3,196 acres 

 of potatoes were listed for inspection. 2,429 acres passed the inspections 

 and were certified. The average yield per acre of fields that were 

 certified was 166.8 bushels. Michigan's estimated average yield 

 per acre of potatoes for 1922 was 104 bushels. Forty-eight counties 

 undertook the inspection and certification of seed potatoes in 1922. 

 There will be offered for sale during the season 1922-1923 approximately 

 270,000 bushels of certified seed potatoes at a premium of approximately 

 60 cents a bushel over U. S. No. 1 table stock. 



The inspection and certification work has stimulated an interest in 

 seed treatment, high pressure spraying, better seed, etc. 



To compare Michigan certified seed potatoes with seed from other 

 sources, over 1,000 bushels of Michigan certified seed were placed in 

 tests in southern Michigan, Iowa, Indiana, Illinois, Ohio and Pennsyl- 

 vania. In each test the Michigan certified seed and the seed with which 



