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IOWA DEPARTMENT OF AGRICULTURE 



order to have the trees shade off the side branches early in their 

 growth. Because of the hardiness of this species, it is often possible to 

 use seedling trees 8 to 12 inches in height, which can be grown in three 

 years. 



The jack pine has little value for ornamental planting, due to its thin 

 foliage and somewhat scrubby appearance. 



■svESTE'RN YEIJLOW PINE (BULL PINE) — (Pimis ponclerosa). 



The Tree: The western yellow pine is a native of the western part 

 of the United States. The range of one form of this pine extends as far 

 east as South Dakota and Nebraska. The resistance of the tree to ad- 

 verse climatic conditions has been largely responsible for the extension ot 

 its range by planting. It is found under a great variety of soil, 

 moisture and climatic conditions.* It makes a splendid lumber tree in 

 the west coast mountains where there is an abundance of moisture and 

 it is the only one of commercial importance in large areas of the dry 

 southwest and eastern foothills of the rocky mountains. 



The mature trees are large, sometimes reaching a diameter of 7 or 

 more feet and a height of 200 feet. The bark on old trees has a dis- 

 tinctive yellow color and a plated appearance, while that on the young 

 ones has a more blackish color. The trees are very intolerant of shade, 

 except when young. The crowns are quite dense in youth but become 

 more open as the trees increase in size. The foliage is coarse in ap- 



Fig. v 

 Black Hills ^,1J 

 the relatively 



slow growth of the bpruce. 



pine (left) and 

 \ eai b old. Note 



