192 



Bulletin 228. 



the vigor of growth is lessened. It is, therefore, unwise to cut a 

 large quantity of potatoes much in advance of the anticipated 

 planting, as an untimely rain may delay the planting for days or 

 weeks, much to the injury of the seed. Dusting the seed with land 

 plaster or gypsum as they are cut lessens the liability to injury if 

 not planted at once. 



Several experimenters have reported increased yields resulting 

 from treating the cut seed with plaster irrespective of any delay in 

 planting. In 1903 the following data bearing on this point was 

 obtained at this Station. The tubers were cut one or two days 

 before planting and well dusted with plaster, except enough seed 

 which was not treated of each of several varieties to plant one row 

 across the field. The results computed to bushels per acre were as 

 follows : 



With 

 plaster. 



No 

 plaster. 



Gain 

 or loss. 



Bovee 



Irish Cobbler 



Doe's Pride 



Green Mountain (late planted) 

 Doe's Pride (late planted) 



246.12 

 174.78 

 321.46 

 137.87 

 211.56 



223.09 

 182.40 

 315.81 

 174.56 

 185.38 



+ 23.03 

 — 7.62 

 + 5.65 

 + 13.31 

 + 26.18 



In three of the five tests, there was a substantial gain when the 

 seed was dusted with plaster. In two cases there was no consider- 

 able effect produced. This treatment is so simple and inexpensive 

 and the results of experiments so favorable, that its more general 

 adoption in practice would seem to be commendable. 



Planting. Because of the tillage value of a thorough stirring of 

 the soil at planting time, the method of doing the planting in our 

 experimental work has been described in part on p. 431 under "Pre- 

 paration of the seed-bed." It is not expected or advised that 

 farmers shall undertake to do the work in just the way we have 

 done, but they endeavor to secure the same conditions we have 

 secured: viz., the placing^of the seed pieces well down in a thoroughly 

 mellowed seed-bed. 



As already stated, the tubers are borne on underground branches 

 that spring out from joints that form on the main stems between 

 the sets and the surface of the ground. Manifestly, then, there should 

 be considerable distance between the point where the stem starts 

 from the seed pieces and the surface of the ground in order that 

 there may be abundant opportunity to form joints and throw out 

 tuber-bearing branches. The general practice of farmers is not to 



