64 The Colorado Experiment Station. 
fective seed or seed asleep. (3) Disease or rot. (4) Defective 
planting. (5) Large and uneven or poorly cut seed. (6) Culti¬ 
vation. 
1. Dryness of Seed Bed. —The upper picture Plate XXII shows 
a potato field the near part of which had been used for a sheep feed 
lot the second winter previous and was cleaned up only in time to 
plow. The pens had been hard tramped and thoroughly dried down 
deep, while the bents had been well mulched with the litter of the 
hay, and were in good moisture condition. Potatoes will sprout 
without moisture, but they will not root unless moist earth touches 
the seed piece. Therefore, summer fallowing, fall plowing with 
spring tillage, or irrigation before plowing, or ditching and irriga¬ 
tion before or after planting, are absolutely necessary to be sure of 
stand. Potatoes must be planted deep enough for the moisture 
level to remain in touch with them even if the surface dries after 
planting. 
2. Defective Seed or Seed Asleep. —Seed that is slow, from 
drying, heating, over sprouting or disease may rot before it roots 
well, so that the little plant loses the impulse of the food in the seed 
piece. Late varieties may partially recover from such a set back 
but early sorts cannot. Seed potatoes should be held asleep by cold 
storing but should be awakened in time to be ready to grow when 
planted. In moist soil five days from planting we have noted on 
potatoes that had stubby sprouts when planted, roots three inches 
long, while similar seed that had not started or had had the sprouts 
broken off showed roots only 1 to ij4 inches long. * 
3. Disease or Rot. —Potatoes affected with Fusarium will 
often rot completely before the plants get a good start, or before 
they start at all. This is particularly true if the seed bed be dry and 
rains come after an interval. And such plants as do start are often 
killed by the disease soon after or even before they come out of the 
ground, f 
4. Defective Planters and Planting. —Not less than 15 per 
cent, loss in stands the state over is due to this cause, and for the 
most part to the sort of defective pickers shown in the right of the 
illustration, Plate XXII, which let go the seed piece in the hopper, 
instead of holding it, as do those to the left, until the seed piece is 
*The greenhouse picture Plate XXII shows one row of Pearls in pots 
that had been held warm long enough to wake them up ready to grow, 
and two rows of pots with the same kind which were still dormant when 
planted on the same date. The plant that establishes itself quickly is 
much surer to grow and to do well. 
f Some experiments indicate that the rotting of seed may be partially 
controlled by the use of lime on the seed. This is a matter which we 
hope to take up thoroughly in 1911 and 1912. Rotting of seed already 
reduces our potato output in Colorado at least $200,000 yearly. 
