18 The Colorado Experiment Station. 
success in the Greeley district. All these crops but one have been, 
practically, failures.* 
*The first year the cultivation was largely with a shallow cultivator. 
While the soil was kept loose on the top it was not loosened at a sufficient 
depth to affect the tubers, and almost total failure resulted. 
The second year about two acres were planted on the west college 
farm and cultivation was given soon after planting. In this cultivation 
the soil was loosened to a depth below the plowing, or from nine to 
twelve inches. A second cultivation of the same character was given 
soon after the plants appeared above the ground. No more cultivating 
was done but the land was ditched twice with a shovel plow which was 
equivalent to at least one cultivation. Although this soil is decidedly 
heavy, these cultivations loosened up the soil below where the tubers were 
formed. No heavy rains occurred to pack this soil and at digging time 
the soil was loose as deep as the tubers were set. This year a good crop 
was secured. 
The third year the same ground was again planted to potatoes, mak¬ 
ing it the second crop after alfalfa, and another plot was planted on 
freshly broken alfalfa land. The same kind of cultivation was given and 
the soil kept in the best of condition till the middle of July. At this 
time the potato tops were sufficiently large to cover the ground and the 
tubers had reached the size of from one-half to an inch in diameter. Heavy 
rains following for one week packed the soil to such a condition that a 
spade was required to dig into the hills. After this packing of the soil 
there was practically no growth of tubers and although a month elapsed 
before frost came, and there was no disease of importance to be found, 
the tubers did not reach marketable size. 
The same season a plot of nearly an acre was planted about three 
weeks earlier than the main crop. Heavy rains followed this planting 
and caused the soil to become packed and sticky. A good stand of plants 
was secured but most of the plants became diseased soon after pricking 
through the ground, and no amount of cultivating could loosen this soil 
sufficiently to even make a good growth of vines. Almost no tubers were 
secured from these plots. 
The fourth year the same plots were planted again with an additional 
plot of freshly broken alfalfa land. This year’s experience was to a great 
extent similar to the year previous. Dry weather prevailed during the 
early part of the season which gave the plants a good start in loose soil; 
later in the season heavy rains packed the soil about the time that tuber 
growth commenced. These plants were comparatively free from disease 
but made very little tuber growth although the vines were of average size. 
What tubers were formed in the compact soils during these three 
years of failures on the college farm, were distorted in form so as not to 
follow the type of the varieties. 
The fifth season (1910) potatoes were planted on another plot of 
freshly broken alfalfa, with soil similar to the other place. This season 
heavy rains followed the plowing even before the potatoes were planted. 
In order to overcome the packing of the soil by the rains a deep cultiva¬ 
tion was given this soil before planting. This went far toward putting the 
soil in better condition but tended toward drying the soil more than was 
good for the plants. A fair stand of plants was secured, however, and 
growth was about normal until the latter part of the season when heavy 
rains again offset the work of deep cultivation. Some marketable tubers 
were secured but as a whole the crop was a failure. 
This experience is not only true of the plots on the college farm, but 
is the experience of growers for the past twenty years in a large part 
of the districts along the foothills of the East Slope, and in the Arkansas 
Valley. 
We believe that the character of the soil in regard to being packed 
by rains in addition to their becoming sticky and so excluding air, during 
