50 



BULLETIN" 299, U. S. DEPARTMENT OF AGRICULTURE. 



Table 22. — Relation of crown class, age and size of trees, and size of crown, to rate oj 

 growth in diameter and volume of white ash in New York, growing in comparatively 

 even-aged dense stands — Continued. 



TREES ON CLAY SOIL, OTSEGO COUNTY, NEW YORK. 





Average. 



Average crown. 



Growth in last 

 10 years. 



Crown class. 



Age. 



Diam- 

 eter 



breast- 

 high. 



Height. 



Length. 



Width. 



Branch- 

 wood 

 2 inches 

 or more 

 in di- 

 ameter. 



In di- 

 ameter. 



In vol- 

 ume of 

 stem- 

 wood 

 inside 

 bark. 



Basis. 



Suppressed 



Dominant 



Codominant 



Intermediate 



Predominant 



Dominant 



Codominant 



Intermediate 



Suppressed 



Years. 

 66 



75 

 76 

 76 



105 

 105 

 105 

 104 



106 



Inches. 

 7.0 



13.6 

 12.5 

 9.7 



19.7 

 15.8 

 12.5 

 11.6 

 9.6 



Feet. 

 68.1 



83.6 

 85.5 

 77.9 



94.6 

 89.9 

 83.4 

 80.3 

 78.3 



Feet. 

 12.0 



29.3 

 24.4 

 22.1 



40.0 

 28.7 

 20.1 

 26.5 

 30.5 



Feet. 

 13.0 



20.1 

 15.7 

 12.4 



24.0 

 18.7 

 14.2 

 14.5 

 13.0 



Cu.ft. 



Inches. 

 1.2 



2.0 

 1.3 

 1.0 



2.1 

 1.4 

 .7 

 1.0 

 1.2 



Cu.ft. 

 2.62 



9.68 



6.96 

 4.09 



16.33 

 9.44 

 3.95 

 4.38 

 4.24 



Trees. 

 1 



2.57 

 1.83 



.54 



9.50 

 4.32 



1.44 

 1.50 



.38 



7 

 8 

 4 



1 

 10 

 8 

 2 

 2 



Liberal growing space for crowns is especially important for ash 

 over 35 years old, to enable it to lay on diameter growth. In general, 

 however, trees in stands under 35 years of age should be kept slightly 

 crowded, being given a medium to heavy underthinning every five 

 to ten years, preferably commencing when the stand is 15 to 20 years 

 old. When 35 to 40 years old the stand should be heavily thinned, 

 amounting to a partial clearance on good sites, and the crowns of the 

 remaining trees left free on all sides. 



Ash on poorer sites is more intolerant and natural thinning more 

 rapid than on good sites; so that the better the site the more impor- 

 tant it is to thin and the greater the yield from thinnings. Figures 

 on the rate of growth of individual trees on sandy and clay soils in 

 New York (see Table 7) show faster growth in diameter and volume 

 during youth on the poorer sandy site, while the reverse would have 

 been the case if the stand on the better clay site had been thinned. 

 In unthinned stands of ash under 50 years of age, the board foot 

 yield and stumpage value per acre may be actually greater on a poorer 

 site because of more rapid natural thinning and higher average 

 diameters, although the total yield in cubic feet, number of trees 

 per acre and height of stand is always greater on the better sites; 

 this emphasizes the importance of thinnings in ash stands on good 

 sites to concentrate the diameter growth into a smaller number of 

 trees. 



Money returns from thinning ash stands are already a possibility 

 in some parts of the country, and as the supply of ash decreases thin- 

 nings will become more and more profitable. The yield from thin- 

 nings in some cases can be expected to equal 20 per cent or more of 

 the returns from final cuttings of mature stands. 



