47 



mental planting, use trees 3 to 4 feet high. For the woodlot, 

 transplants 10 to 12 inches high, which are three to four years 

 old, are of a convenient size and more economical. 



NORWAY SPRUCE ( Picea excelsa ) 



The Tree : The Norway spruce is not native to North 

 America but has been introduced from northern Europe and 

 Asia. The tree develops a straight trunk and a pyramidal 

 crown which becomes rounded at the top as the tree becomes 

 old. In a dense stand the tree retains its pyramidal form but 

 the living portion of the crown is restricted to the upper part 

 of the trunk. The slender branches become more or less pen- 

 dulous as the tree increases in age, which makes it valuable 

 for ornamental planting. The tree reaches a good size in Iowa 

 even on upland soil. For the higher situations where there is 

 plenty of moisture, 

 this spruce is much 

 more valuable 

 than the white or 

 Black Hills vari- 

 ety, due to its 

 more rapid and 

 thrifty growth. 

 This species will 

 not endure a very 

 dry soil but will 

 thrive on one of 

 moderate fertility 

 if surface mois- 

 ture is available 

 for the shallow 

 root system. The 

 thee will with- 

 stand wet situa- 

 tions but not stag- 

 nant or swampy 

 areas. The growth 

 during the first 10 

 or 12 years is 

 rather slow but 

 the rate increases 

 after that time 

 and continues un- 

 til the trees are 

 about thirty-five 



years of age. The length of life when grown in Iowa under 

 good conditions is not definitely known. 



Fig. 12 The Norway is the most desirable spruce 

 for windbreak and shelterbelt planting- in Iowa. 

 Open grown trees are very desirable for lawn plant- 

 ing. 



