PRODUCTIVITY OF RECENTLY CUT LANDS 



259 



Proportion of 

 Total area of all commercial 

 type group ' forest area 

 (willioii acres) (percent) 

 Forest type groups with more than 

 70 percent of recently cut 

 lands in the upper produc- 

 tivity chiss (exceeding the 

 national average 2): 

 Eastern hardwoods: 



Maple-beech-bircli 33. 45 0. 8 



Aspen-birch 23.45 4.8 



Total 56.90 11. (i 



Western softwoods: 



Douglas-fir 31.73 6.5 



Hemlock-spruce 7.81 1.6 



Redwood 1.59 .3 



Ponderosa pine 37.46 7.7 



Lodgepole pine 14.47 3.0 



Fir-spruce 13.62 2.8 



Total 106.68 21.9 



Western liardwoods 3.94 .8 



Total 167.52 34.3 



F'orest type groups with 60-70 

 percent of recently cut lands 

 in the upper productivity class 

 (approximately the national 

 average 2) : 

 Eastern softwoods: 



Spruce-fir 21.46 4.4 



Longleaf-slash pine 26.49 5.4 



Total 47.95 9.8 



I Forest type groups with less than 

 60 percent of recently cut 

 lands in the upper produc- 

 tivity class (below the national 

 average ^) : 

 Eastern softwoods: 



White-red-jack pine 10.30 2.1 



Loblolly-shortleaf pine 58.51 12.0 



Total 68.81 14.1 



Eastern mixed types: 



Oak-pine 22.89 4.7 



Oak-gum-cypress 40. 29 8. 3 



Total 63.18 13.0 



Eastern hardwoods: 



Oak-hickory 112.21 23.1 



Elm-ash-cottonwood 18. 28 3. 7 



Total 130.49 26.8 



Western softwoods: 



Western white pine 5. 38 1. 1 



Larch 4.42 .9 



Total 9.80 2.0 



Total 272.28 55.9 



' The total of all type group areas falls short of the total 

 commercial forest area by the acreage in the pinyon- 

 juniper type of the West in which no recently cut lands 

 were examined. 



2 In this tabulation, the national average percentage of 

 recently cut lands in the upper productivity class is taken as 

 a range of 60 to 70 percent rather than the mean of 65 

 percent. This range was indicated by the sampling ac- 

 curacy of estimate shown in tabie 84, appendix section 

 Adequacy of Data. 



Hardwood Type Groups of Largest Area 

 Below Average in Productivity 



The oak-hickory and clm-ash-cottouwood type 

 groups coiistituto the major weaknesses in hard- 

 woods. Tiieir combined area comprises 27 percent 

 of all commercial forest land. The oak-hickory 

 group with its many important sid>types covers 

 more commercial forest land (112 million acres) 

 than any other type group. It is widely dis- 

 tributed over both the Nortli and tlie South, as is 

 the smaller elm-ash-cottonwood group. The com- 

 bined area of these two type groups (130 million 

 acres) is over twice as large as the combined area 

 of the maple-beech-bircli and aspen-birch type 

 groups, on which productivity of recently cut 

 lands exceeds the national average. 



Weak Spots by Forest Type Groups 

 Identified by Rating Element and 

 Ownership Class 



In table 149, the deductions for each type 

 group and ownership class represent the propor- 

 tion of recently cut lands which did not qualify 

 for the standards set up in the Criteria. For 

 example, 35 percent of recently cut lands of the 

 white-red-jack pine type group on small owner- 

 ships met all standards of the Criteria sufficienth- 

 well to qualify for the upper productivity class. 

 The deductions show that 46 percent of recently 

 cut lands did not qualify for the upper class be- 

 cause stocking standards were not reached. Seven 

 percent of the area of recently cut lands was lost 

 to the upper class because the composition 

 standard was not reached, and another 12 percent 

 was lost due to premature cutting. The sima of 

 the deductions and the proportion of area in the 

 upper productivity class always equals 100, thus 

 accounting for all recently cut land in each 

 forest type group-owner class combination. 



The deduction of 46 percent because of stocking 

 in the white-red-jack pine type group in small 

 ownerships is greater than the average stocking 

 deduction for all type groups on all ownerships 

 (26 percent). Thus, stocking in this type group 

 on small private ownerships is deficient in com- 

 parison with average stocking countrywide, and 

 this tends to hold down or place limitations on 

 the national level of growth. All such compari- 

 sons from table 149 (indicated by boldface type) 

 were used as the basis for identifying weak spots. 

 The major weak spots are shown in figure 85. 



Stocking Deficiencies Mainly in Softwood 

 Type Groups on Small Ownerships 



The boldface figures in table 149 reaffirm a 

 previous finding that stocking on small private 

 ownerships is a major reason why the recently 

 cut lands on such ownerships are below the 



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