14 BULLETIN 1113, U. S. DEPARTMENT OF AGRICULTUEE. 



shown to winterkilling and drying out for lack of moisture. In cer- 

 tain sections it has made an excellent growth, but it can not yet be 

 recommended for general use, 



CONIFEROUS OR EVERGREEN SPECIES INTRODUCED TO THE REGION. 



Scotch pine. — The Scotch pine {Pinus sylvestris) is a native of 

 northern Europe and Asia and has been widely planted in the United 

 States. It grows successfully on the prairies east of the Great Plains 

 region, and recent plantings within the region indicate that it is one 

 of the best evergreens for shelter-belt use. It is not as well adapted 

 to sand and gravel soil as the j ack pine and does not do well in moist 

 or low, wet situations. 



Jack pine. — The jack pine {Pinus divaricata) is found extensively 

 on the more sandy soils of northern Minnesota. It is adapted to 

 shelter-belt planting on the Great Plains, especially on sandy soil. 



|^^*f:.Jr~-'**™*^" 



Fig. 8. — A shelter toelt near Isabel, S. Dak. In the foreground are Scotch pines planted in 

 1920 and jack pines planted in 1921 in east and west rows on the south side of the 

 broadleaf section planted in 1916. Photographed in July, 1921. 



It does not do well on clay soil and should not be placed in moist or 

 low, wet situations. 



White spruce. — The white spruce (Picea canadensis) has a wide 

 range in northern Minnesota and Canada. It is adapted to shelter- 

 belt planting on the Great Plains and is suitable for practically all 

 types of soil. It will grow in either wet or dry situations. 



Blue spruce. — The blue spruce, or Colorado blue spruce {Picea 

 parryana) , is native to the Eocky Mountains of Colorado, Utah, and 

 Wyoming. It appears to be perfectly hardy when planted in shelter 

 belts in the northern Great Plains. It is more exacting as to soil 

 requirements than the white spruce, showing preference for clay 

 soils. 



TREES IN RELATION TO SOIL TYPES. 



Not all species of trees adapted to this region grow equally well on 

 the same type of soil. The typical shelter-belt planting site is on 

 the open upland prairie where the soil texture falls into the general 



