682 TIMBER RESOURCES FOR AJ^'IERICA'S FUTFRE 



Table 91. — Classification of species according to forest type group and site, Lake States Region 





Aspen-paper birch type 

 group 



Spruce-fir type 



group 



White-red-jack pine type group 



Maple-beech- 

 birch type 



Oak -hickory type 

 group 



Species 



Site 

 index 

 60+ 



Site 

 index 

 45-60 



Site 

 index 

 under 



45' 



Swamp 

 black 



spruce- 

 tama- 

 rack 



Other spruce-fir 



Jack 



pine 



Red and white 

 pine 



group 



Mer- 

 chant- 

 able 

 height at 

 60 years, 

 12 feet 

 or more 



Mer- 

 chant- 

 able 



-_ 



Up- 

 land 



Swamp 



Site 

 index 

 50+ 



Site in- 

 dex un- 

 der 50 



Site in- 

 dex un- 

 der 65 



Site 

 index 



65+ 



Up- 

 land 



Low- 

 land 



height at 



60 years, 



imder 



12 feet 



Ash, black _ . 



A 

 A 

 D 

 D 

 3 A 

 D 











A 











A 



A 







Ash, green_. , . , 



















A 

 D 

 A 

 3 A 

 D 

 A 

 A 

 A 



? 



A 

 A 

 A 





\sh, whire- - -_ 













A 

 A 









D 



A 

 'A 



D 



A 



D 



A 



A 



A 



D 



A 

 45 A 



D 



a" 



3 A 

 ....... 



A 



r 



D 

 D 



A 





Aspen. _. 



A 







A 



3A 



D 



»A 





A 



A 





Balm-of-Gilead 









Basswood 











A 







A 





Beech . 















Birch, yellow . ... 



D 

 D 

 A 

 A 

 D 

 A 

 D 

 D 









D 



A 



»A 

 2A 



A 

 A 







A 

 A 





Birch, paper . . . 



A 













Cherrv, black 













Elm, .\merican 











A 

 A 

 A 

 D 



A 













Elm, rock . . 











A 











Elm, slippery 



















Fir, balsam... 



D 





A 



D 

 D 



A 



A 





A 



A 

 A 





Hemlock 



















A 





Maple, red 



A 





















A 



D 





Maple, sugar. . 









*D 





A 



« A 



9A 



6A 

 A 

 A 

 D 

 D 

 D 

 D 

 D 







« A 



A 

 D 





Oak, black- . .. 

















A 









A 











A 



A 



A 



Oak, pin 















A 





D 









D 









A 



D 



D 



D 

 D 



A 



Oak white 

















i3 



D 



g 

 D 

 A 



D 

 D 

 D 



D 

 D 



A 



"a '" 









D 

 D 



A 

 A 

 A 



D 

 D 

 D 



A 

 D 



A 

 D 

 D 



A 

 D 







D 





A 



'A 



D 

 D 

 D 

 D 



A 



D 

 D 

 D 









D 



Pine, white 



D 



D 

 D 

 D 













Spruce, white 













Walnut, black 



















D 







A 







A 



A 



D 









A 



A 



A 





















A = .A.cceptable. D = Desirable. 



1 This classification was used for all aspen-paper birch in Xorth Dakota. 



' Noncount on peat swamps. 



' Noncount except where it was readily accepted on the market. 



* Noncount in most of northern Minnesota. 



5 Desirable in northern Minnesota. 

 * Noncount on sites where site index was under 65. 



" Desirable if tamarack made up more than 50 percent of stand before 

 cutting. 



stocking based on proximity to the margin of 

 groups, strips, or stands of seed-bearing trees: 



Slocking 



Distance from seed source (chains) : (percent) 



0-3 100 



3-6 80 



6-9 60 



9-12 40 



12-15 20 



15+ 



White-Red- Jack Pine Type Group 



Jack pine. — Prospective stocking was consid- 

 ered only if the stand w^as cut less than 5 years 

 prior to examination. Because seed in slash is 

 very important, it was credited in the rating. 

 The importance of mineral-soil exposure and ab- 

 sence of ground cover also affected the rating. 

 Standards were not specified but were left to the 

 judgment of the examiners. 



Red and white pine. — Prospective stocking was 

 considered only if the stand was cut less than 5 

 years prior to examination. The following stand- 

 ards were used: 



Seed trees per acre 12 inches d. b. h. and expected 



larger (number) : (p'ercent) 



2-4 20 



5-7 40 



8-11 60 



12-15 80 



16+ 100 



No trees less than 12 inches d. b. h. were recog- 

 nized as seed trees and no prospective stocking 

 considered from seed margins of green timber. 



Maple-Beech-Birch Type Group 



Prospective stocking was considered only if the 

 stand was cut less than 3 years prior to the exami- 

 nation. Ten seed trees per acre of desirable species 

 not less than 10 inches d. b. h. w^re credited with 

 producing enough seed to fully restock the area. 

 The following standards, based on pro.ximity 

 to an adjacent seed-bearing timber stand, were 

 used: 



-r->. i- 1 • . . 1 r Stockino 



Distance from seed source in multiples of txpecied 



tree height: (perceno 



0-1 100 



1-2 50 



2-3 25 



3-4 10 



More than 4 



