53 



For commercial planting the white cedar could be well 

 utilized on wet land. It should produce a crop of fence posts 

 in 15 to 20 years but would give best returns if permitted to 

 grow for 30 to 40 years, since the initial growth is slow. In 

 planting use trees 8 to 12 inches high. 



This cedar is very much prized for ornamental planting 

 on lawns. It trims back readily and is used much for low 

 hedges, although foreign varieties are more adaptable for this 

 purpose but are not as hardy. For lawn planting, trees up to 

 3 feet in height can be satisfactorily planted if given good care. 



HEMLOCK ( Tsuga canadensis ) 



The eastern hemlock is a native to northeastern United 

 States and extends as far west as the Lake States. It is a very 

 desirable tree for ornamental planting, due to its symmetry and 

 to the graceful, drooping, soft foliage. It is suitable for plant- 

 ing on moist situations but is difficult to establish on upland 

 soil where it is exposed to the summer winds. 



The tree has little value for commercial plantations, becaus 

 of the inferior quality of the wood. It is occasionally used 

 for windbreak planting. 



DOUGLAS FIR(Pseudot8uga taxi folia) 



The Douglas fir is native to the Rocky Mountain region 

 and western United States. Individual trees in Iowa appear 



Fig-. 16. A young windbreak of Austrian pine (left), Douglas fir (center) 

 and red pine (right). All the trees are about ten years old. Note the rela- 

 tively slow growth of the Douglas fir. 



