3320 Chapter 27 



Quality of logging residues. — The size and quality of logging residues can 

 limit their possible uses. Timson (1980) established four quality levels for 

 residues based on length, surface defects, and sweep. After examining 25 

 hardwood sawlog-only operations in West Virginia, Virginia, and Pennsylva- 

 nia, he found that 74 percent of the residues would not qualify as "local use" 

 logs. Eighty-six percent would not meet factory grade 3 standards. Timson 

 concluded that hardwood logging residue can best be used when extracted in the 

 primary harvesting operation and used for bulk products such as energy wood, 

 chips, and pulp wood. 



Another possible use is in mine timber production. Timson's (1978) study in 

 the Appalachian coal region showed that 44 percent of the residue from sawlog- 

 only harvests is physically suitable for mine timbers. In this study only residues 

 at least 4 inches dob at the small end and at least 4 feet long were considered. 

 Fifty-eight percent of the bole wood residue could be used in mine timbers, but 

 only 26 percent of the limbwood residue was acceptable. The oaks and hickor- 

 ies — ^preferred species used for all purposes in mines — and yellow poplar — a 

 nonpreferred species used primarily in noncritical areas — all had about 60 per- 

 cent usable bolewood residue. 



FOLIAGE AND SEED 



Section 15-2, FOLIAGE QUANTITY, contains information on the number of 

 leaves, leaf surface areas, foliage weights, and the proportion of complete-tree 

 weight contributed by leaves (see tables 15-6 through 15-11, figs. 15-11 through 

 15-13). In general, ovendry foliage weights range from about 3 to 9 percent of 

 the whole-tree weight (above-ground portions only), depending on tree size and 

 species (table 15-7). When the complete-tree biomass is considered (including 

 stump, taproot, and major lateral roots), leaves account for 2. 1 to 6.9 percent of 

 the total ovendry weight, and the variation appears to be a function more of tree 

 dbh than of forest type (table 16-4). For 6-inch hardwoods growing on southern 

 pine sites, foliage contributed from 1.4 to 4.5 percent of the complete-tree 

 weight (ovendry basis); green ash had the least percent leaves, with 2.5 pounds 

 per tree; red maple had the greatest, with 14.3 pounds per tree (table 15-9). 



Annual production of foliage in southern upland hardwoods ranges from 

 about 2,000 to 5,000 pounds per acre (ovendry basis), and the amount of litter in 

 such stands is estimated at 5,000 to 1 1 ,000 pounds per acre (see sect. 15-2, table 

 15-12, and fig. 15-14). For a discussion of the volumes of deer browse contribut- 

 ed by leaves and twigs, see section 15-5, subsection WILDLIFE FOOD (page 

 1390). 



Seed yield per tree and per acre for sweetgum, yellow-poplar, and the oaks is 

 discussed in section 15-7 (see tables 15-24 through 15-26, figs. 15-21 through 

 15-24). 



The number of acorns per pound varies considerably among oak species and 

 also within species and with season. See table 15-23 and adjacent tabulations 

 and text. 



