
Agriculturalists agree that use as grassland would result in a higher income, 
even considering the small size of the farming units, which average about 
320 acres (U. S. Dept. of Commerce, 1945). The main obstacles to the shift 
to grassland farming in this area are resistance to change, and the period 
of resulting lower income which would occur during the changeover period. 
Limitations of rainfall and the mechanical difficulties of cultivation in 
this area lead to low incomes, even with present high prices and over-intensive 
use of the land. 
Farming practices have considerable effect on the water areas themselves, 
not only through grazing, haying, and burning, but also through complete 
plowing of the bottoms of the more temporary areas. 
Classification of potholes 
The term "pothole" in this report refers to the depressions in glacial 
moraine which become filled with runoff waters from the surrounding slopes. 
There is no evidence that water levels are influenced in this region by a 
general water table. Classification of potholes on the study area has been 
based largely on their longevity, or the length of time they retain water each 
year, and is presented on the basis of the "WETLAND CLASSIFICATION (PRAIRIE 
POTHOLE DIVISION)" derived from Martin et al. (1953). The classes of areas are 
described below. 
ales ceasonally flooded basins: 
la. Intermittent areas: Shallow depressions that contain standing 
water for only a few days in a wet spring or after heavy rains 
and are generally not more than 20 inches deep at any time. 
They will never hold water through June 1, and in many years 
they will be dry throughout the season. Very few of these areas 
have an effect on crop production except to retard seeding in 
years of heavy runoff. Upland plants are abundant, and scattered 
wetland plants include smartweeds, sedges, spikerush, whitetop, 
burreeds, and water plantain.. However, these areas may be 
plowed or grazed to the extent that no wetland vegetation is 
visible. 
lb. Temporary marshes: Shallow depressions that usually contain 
water for a few weeks in the spring and after heavy rains. 
They may hold water through June and into July in years of 
heavy runoff. They may hold up to 24 inches of water in the 
spring of such a year, or may be completely dry after an open 
winter. These areas are all capable of bearing such species as 
smartweeds, sedges, spikerush, slough grass, mannagrass, white- 
top, water plantain, and burreeds, unless the vegetation is 
removed by cultivation or grazing. In dry or moderately wet 
years crops may be raised in these areas. In wet years they are 
flooded too long for cultivation. 
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