686 TIMBER RESOURCES FOR AMERICA'S FUTURE 



Table 96. — Trees required per acre for full stocking, by tree size, forest type group, and site, Central Region 



Diameter breast high (inches) 



Elm-ash-cott 



onwood, oak-hickory, and oak-pine type 

 groups 



Lobloliy- 

 shortleaf 





Excellent 

 sites 1 



Good 



sites 2 



Medium 

 sites 



Poor 

 sites 



pine type 

 group 



Reproduction . -_ . .-_ 



Number 

 1,000 

 800 



600 

 450 



280 

 190 



140 

 105 



80 

 66 



55 

 45 



38 

 33 



28 

 24 



21 

 19 



17 



Niimber 

 1,000 

 800 



600 

 400 



240 

 155 



115 

 90 



70 

 55 



45 

 38 



32 



27 



23 



20 



Number 

 1,000 

 800 



600 

 360 



220 

 145 



100 

 80 



60 

 46 



38 

 31 



26 



Number 

 1,000 

 800 



600 

 300 



170 

 110 



80 

 60 



45 

 35 



30 

 25 



20 



Number 

 1, 000 



2 



800 



4 .. ... 



600 



6 -- . --. 



400 



8 . --. .. 



230 



10 . -- ... - 



155 



12 



115 



14 __ __- .. _. . 



90 



16 



72 



18 



60 



20 



50 



22 . 



42 



24 .. __. 



35 



26 





28 - -. 









30 . - -. 









32 









34 - . . 











36 





















' This standard was used for most bottom-land hardwood 

 sites and for the best of the upland hardwood sites. 



2 This standard also used for all sites of the maple-beech- 

 birch forest type group and the best of the oak-pine sites 



insure sprouts that would develop into crop trees. 



If the logging resulted in large stumps, or if 

 the stumps were of species incapable of sprouting 

 or consisted for the most part of acceptable or 

 noncount species, the rating was then based largely 

 on the adequacy of the seed source. 



The standards for individual seed trees and for 

 adjacent margins of seed-bearing stands were 

 identical to the standards used for the oak -hickory 

 type group in the Lake States Region. 



Loblolly- Shortleaf Pine Type Group 



The standards used for prospective stocking 

 were as follows: 



Average number of pines required 

 per acre to rate 100 percent for 

 Diameter breast high (inches) : seed-tree requirements 



8 20 



10 15 



12 12^2 



14 10 



16 ly, 



18+ 4>^ 



Standards for determining prospective 



stocking, based on proximity to 



pine seed source 



Good seed Fair seed Poor seed 



Distance from seed source source ' source 



source (chains): (percent) (percent) (percent) 



0-2 100 100 30 



2-4 - ... 100 80 20 



4-6 100 40 10 



6-8 80 30 5 



8-10 40 10 



10-12 10 5 



12-H ... 



' In Kentucky this column only was used. 



Classification of adjacent timber stands as a 

 "good," "fair," or "poor" seed source was deter- 

 mined by field examiners on the basis of judgment. 



Effect of Felling Age 



The felling-age factors showing the effect of cut- 

 ting trees prior to the culmination of tlie mean 

 annual growth are shown in table 97 for various 

 species and sites. 



