EXPERIMENT STATION REPORTS. 309 



conditions and ibetter cultural methods. In this case we have a quantity 

 of seed with a known parentage, and common origin, but grown under 

 many and varying conditions tliat would tend to prove that with good 

 seed, sufficient fertility, proper spraying, and with soil in good physical 

 condition, yield can be fairly well stabilized. 



SEED TREATMENT 



Proper seed treatment of potatoes is one of the requirements of the 

 Michigan Potato Producers' Association. Through the influence of 

 this organization, the practice of spraying increased to the extent of 

 64%, in 1922 as compared to 1921. The practicability of spraying has 

 been fully demonstrated, but as yet only 6% of the acreage in the state 

 is sprayed. 



TIME OF PLANTING 



Demonstrations of time of planting Irish Cobblers were conducted 

 in the northern part of the state, to determine the dates best suited to 

 plant Irish Cobblers in order to get the best results in production of 

 stock for seed. The 1922 results would not conclusively establish a 

 practice. However, for the season of 1922 the dates giving best results 

 on time of planting were between June 5th and 18th, considering largest 

 yields and greatest amount of marketable tubers. 



DISTANCE OF SPACING 



Several demonstrations on distance of spacing were carried on in order 

 to increase yields and decrease oversized tubers. Results with Irish 

 Cobblers indicate that hills 12 inches and 18 inches apart in rows 3 feet 

 apart, gave the largest total yield. The 12 inch spacings, however, had a 

 large number of small potatoes, while the 21 and 30 inch spacings pro- 

 duced fewer potatoes and a number of over-sized unmarketable ones. 



FARM MANAGEMENT STUDIES 



The best place for the potato crop in the rotation is generall}^ conceded 

 to be after a legume crop, especially alfalfa, sAveet clover or common 

 clover. The preparation of this land brings in the question of time 

 of plowing — fall plowing vs. spring plowing of sod on heavy sandy loam 

 soil. The increase of the fall plowed plot over the spring plow^ed plot, 

 of two acres each, resulted in a 50 bushel increase, or 25 bushels per 

 acre. 



PARENT SEED FARMS 



Three farms have been selected for starting tlie work next year, under 

 the parent seed farm project, one farm taking a carload of White 

 Rurals and two farms taking 125 and 75 bushels respectively of Irish 

 Cobblers. 



REPORT ON ACTIVITIES 



The potato program for the state was projected through 25 lecture 

 meetings in the spring with an attendance of 922 people. The field meet- 



