Farm Types in Nebraska 
7 
Eastern coasts have what may be classed as an oceanic cli- 
mate, but it is not as equable as that of western coasts. The 
extreme continental climate is common to the interior of North 
America and Eurasia. In contrast with an oceanic climate, a 
continental climate is variable. Temperature changes are 
more sudden and extreme. Rainfall is comparatively lighter 
and when it comes it is apt to be torrential rather than steady. 
Also when snow falls the ground is seldom covered with a uni- 
form blanket. In general it can be stated that the climates 
found on similar sides of North America and Eurasia are more 
comparable than those found on adjacent sides. This is to a 
less extent true of points in the interior. 
The boundaries of the four great agricultural regions in 
the northern hemisphere are determined by low temperature, 
low rainfall, and coast lines. In southern Canada, Norway, 
Sweden, and Finland, and in northern Russia, Manchuria 
and Japan, agriculture is limited by low temperature. The 
principal agricultural boundaries determined by low rainfall 
in North America are found (1) in the states of the Great 
Plains and (2) in the states of the Pacific coast region. In 
Eurasia the principal agricultural boundaries determined by 
low rainfall are found (1) in southeastern Russia and (2) in 
western China Proper and Manchuria. Figures 1, 2, and 3 
indicate in a diagrammatic way these agricultural boundaries. 
The small circles mark temperature limits, and the dashes 
rainfall limits. 
The northern parts of the two agricultural regions in 
both land masses are connected by a strip of marginal agri- 
cultural country lying between a cold adverse region to the 
north and a dry adverse region to the south. This is roughly 
indicated in the figures by a line made up of both circles and 
dashes. It is possible that these strips of country are deter- 
mined by the fact that to the south higher temperature makes 
droughts very destructive while to the north the lack of heat 
during the growing season soon comes to act as an absolute 
limit to ordinary agriculture. 
Soil has but little visible effect upon the boundaries of 
these agricultural regions. Considered on any large geo- 
