THE PLAINS SHELTERBELT PROJECT 271 



already established but will include additional governmental nurseries, 

 using all the trained personnel wherever available. Many state for- 

 esters and their staffs and private nurserymen have acquired a great 

 deal of valuable experience during the past 30 years or more in grow- 

 ing and planting trees in this region. This experience will be fully 

 utilized to obtain the most efficient and prompt results. 



Trees are generally grown in nurseries for one to two years. Many 

 of the hardwoods develop large root systems and are sufficiently grown 

 to transplant from the nurseries to the shelterbelt at the end of one 

 year. Large trees will not be used because of the expense of trans- 

 porting from the nursery to the field and the difficulty of survival. 



Assuming that the program will consist of a maximum of 100,000 

 miles of shelterbelt plantings, the following statistics are of interest: 

 The length will be approximately 1000 miles from Canada to the Red 

 River section in Texas ; the width will be approximately 100 miles with 

 the western limit at approximately 18 inches of average annual pre- 

 cipitation. The gross area of the zone is about 100,000 square miles 

 or 64 million acres. The shelterbelt strips will be 8 rods or 132 feet 

 wide or, when fenced, 10 rods or 165 feet wide. The direction of the 

 individual shelterbelt strips will be determined by the prevailing 

 winds. The total planting area will be approximately 1,600,000 acres, 

 or 16 acres per square mile; when fenced, the total area will include 

 about 2 million acres, or 20 acres per square mile. 



There will generally be 4 rows of shrubs and 17 rows of trees, 

 making 1732 plants per acre. Thus a total of about 3 billion trees 

 and shrubs will ultimately be planted. The distance between the 

 rows of trees will be 6 and 8 feet, with shrubs 4 feet. The distance 

 between the trees in rows will be 4 feet. 



It is estimated that there will be 212,500 miles of fences. Fence- 

 posts placed 20 feet apart will mean 56,100,000 posts. About 60,000 

 carloads of material will be required, and 16 million man-days will 

 be needed to consummate the work. 



These computations are based upon the maximum possible require- 

 ments. Adjustments as appear advisable by local conditions will prob- 

 ably result in some revisions. 



