Potato Cui^ture in Colorado 
13 
perform its function. This item alone amounts to many thous¬ 
ands of dollars, and even on individual farms is often sufficient 
to decide whether a crop is raised at a profit or at a loss. 
CULTIVATION 
After potatoes have been planted, the spike-tooth harrow 
should be put in use and kept going so that the field will be har¬ 
rowed at least once every week or ten days, until the potatoes 
are about 4 inches above the ground* If there is danger of tearing 
the young plants during the last harrowing, the teeth may be set 
so as to slant away from the draft, which will result in less injury 
to the plants. As soon as the plants are large enough to permit 
of cultivation between rows, the first cultivation should be as 
deep as possible. Eight to ten inches is not too deep. This will 
loosen the sub-soil, and permit the soil to become aerated. As 
the plants increase in size, with a corresponding development of 
the root system, the cultivation should be correspondingly shallow. 
In the right kind of potato soil, the roots of the plant will often 
penetrate to the depth of 2 feet, and laterally 2 or 3 feet. The 
more thorough and frequent the cultivation, the better will be the 
soil conditions for the development of the root system and the 
tubers. On non-irrigated land, the cultivation should be shallow 
throughout the season. 
Hilling 
On level land, deep hilling, is necessary, as standing water 
should not be permitted around the potato plant. On land having 
a good slope, so as to insure perfect drainage, the hilling should 
be less extensive. It is better at least, on land having a slope, to 
hill gradually, as it will keep the soil cooler, and permit the 
breaking up of the crusts by cultivation between irrigations. On 
the level land, little or no cultivation can be done after the hilling. 
Where high hilling is practiced, there is considerable danger of 
over-heating the soil, due to the extensive exposure of the soil 
in the hilling. The undue raising of the temperature in the hill 
creates favorable conditions for very rapid growth of the plant, 
and also very favorable conditions for diseases. The cooler the 
soil can be kept during the warm season, the more normal and 
the more healthy will be the plant. Also, it will be less susceptible 
to disease attack. 
On non-irrigated land, hilling is detrimental, as it tends to 
dry out the soil, and thus deprive the growing potato plant of 
the much needed moisture. Generally all that is needed in the 
way of hilling is accomplished by using a broader tooth in the 
rear of the cultivator, which will throw a small amount of soil 
