THE MONTHLY BULLETIN. 565 



sprouts more quickly than any other part of the tuber. If these sprouts 

 at the bud end are allowed to develop normally into plants without 

 cutting the tuber, a few of these eyes, often only one or two, will use 

 the sugar which is being formed within the tuber and the other eyes on 

 the tuber will not germinate, but will remain permanently dormant. 

 However, if the eyes at the bud end are allowed to germinate and the 

 ycung plants, either purposely or otherwise, are prevented from a con- 

 tinuous growth, then the other eyes will become active and send out 

 sprouts. 



Now how can we apply these fundamental principles of tuber 

 development and germination in handling our seed potatoes'? 



THE USE OF SMALL WHOLE POTATOES FOR SEED. 



Much has been written and spoken regarding the value of planting 

 small whole potatoes; and still many people have tried this plan with 

 disastrous results. In the first place we must remember the origin of 

 the small potatoes usually used for seed purposes in this country. 

 Small potatoes often, if not usually, represent cull potatoes ; that is, 

 they are the tubers which are not large enough for table use and, if used 

 at all, are given to the hogs or taken for seed. Small potatoes when 

 selected in this way are largely composed of tubers from unproductive 

 hills. The most productive hills in a field have few small potatoes ; the 

 unproductive and weak hills have many small potatoes ; hence small 

 potatoes taken from the field run are mostly of inferior productiveness 

 and likely to be diseased as well. Who would expect to get good results 

 from plant seed of any kind, from the poorest plants in a field ? 



However, if the small potatoes have been obtained by methods similar 

 to those for growing certified seed, where the weak hills in the field have 

 been eliminated and the plants have been crowded together on purpose 

 to produce small seed, then many things can be said in favor of using 

 such small seed. But the use of small seed stock without knowing how 

 it has been selected is likely to prove to be poor economy. 



THE SIZE OF SEED PIECE. 



Experiments in this country, as well as abroad, have shown pretty 

 generally that the larger the seed piece the greater the crop. Several 

 things must be taken into consideration here, however. Beyond a cer- 

 tain limit increase in size of seed piece costs more for seed than the 

 increased jdeld amounts to. The condition of the seed when planted is 

 of vital importance. If whole dormant seed is planted we should expect 

 but one or two, or possibly three, of the strong bud eyes to develop into 

 plants. These few plants would be well supplied with food material 

 from the large seed and would get a strong vigorous start even in spite 

 of unfavorable field conditions. But if the seed has germinated suffi- 

 ciently before planting time so that the sprouts are broken off, then, as 

 we have shown above, all the eyes on the whole potato or the large seed 

 piece will develop into plants, which must struggle with each other for 

 food material from the seed before they obtain a foothold in the soil; 

 and then they will demand more plant food in the soil and more 



