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BULLETIN 153, U. S. DEPARTMENT OF AGRICULTURE. 



monly forming its leader from one of the side shoots, it seems best 

 to use a closer spacing, 4 by 4 feet to 4 by 6 feet, in order, if possible, 

 to correct the habit. The stand should then be thinned as soon as 

 needed. 



Green ash has come up naturally under cottonwood, and should 

 prove a good tree for underplanting old stands of that species. 



In the plantations examined ash has not grown as rapidly as in 

 natural stands. Lack of knowledge regarding the tree's requirements 

 is probably responsible for this, and both green and white ash should 

 be given a further trial on various kinds of soil, though it would not 

 pay to plant them on good agricultural land. Young green ash trees 

 are inclined to be somewhat crooked, but the timber is strong and can 

 be used for many purposes on a farm. A valuation of $4 per cord 

 has been put upon cordwood (Table 9), since most of the timber so 

 classed can in fact be put to more valuable use. 



TABLE 9. Yield and value of green ash (Fraxinus lanceolata). 



NORWAY PINE (Pinus resinosa Ait.). 



Norway or red pine is especially adapted for planting on poor, 

 sandy or gravelly soils which will not even support a good growth oi 

 white pine. On good loam soils in Iowa trees 40 years old have 

 reached a height of from 50 to 55 feet and a diameter of 8 inches, 

 while on very poor, sandy soil in Rhode Island and Massachusetts a 

 height of 40 feet and a diameter of 8 to 10 inches have been attained 

 in 40 years. Norway pine is decidely intolerant, and a spacing oi 

 6 by 8 feet is close enough. Planting stock is usually rather expen- 

 sive, because of the difficulty of obtaining seed, and the wide spacing 

 has the additional advantage of reducing the planting costs. 



Norway pine lumber is less valuable than white pine, and the pro- 

 duction per acre is not so large, but the tree is very hardy and excep- 

 tionally free from disease. It is less subject to attack by the pine 



