Stem quality of oak in 15-year-old stands: influence of species within harvesting treatment and fencing

Abstract

The effect of harvesting treatment, fencing, and species on the stem quality of oak (Quercus spp.) was evaluated in mixed-hardwood stands on the Allegheny Plateau in central Pennsylvania. The regeneration harvests included commercial clearcut that removed most stems ≥ 15 cm dbh and a clearcut with timber stand improvement (TSI) that removed all stems ≥ 2.5 cm dbh. Half of each area was fenced with 2.4-m-tall woven wire to prevent browsing by deer (Odocoileus virginianus) on the regeneration. After 15 years, the number of stems ≥ 2.5 cm dbh ranged from 4,865 to 8,416/ha and basal area ranged from 11.2 to 16.8 m²/ha. Growth from age 10 to 15 ranged from 4.9 to 6.7 m²/ha or about 1 m²/ha/yr. The fenced portion of each treatment had more stems and basal area than the unfenced portion. The commercial clearcut had more stems and basal area ilian the clearcut with TSI. Oak composition before harvest was 70 to 80 percent of basal area. At age 15, oak composition ranged from 8 to 41 percent of basal area. Red maple (Acer rubrum) and black cherry (Prunus serotina) along with oaks were the dominant species in the new stands. Potential quality of oak stems was rated by use of a quality classification system that included crown class, crook and sweep, number of limbs, and presence of forks, rot, and seams. Other variables measured included dbh, total height, height to base of live crown, and live-crown ratio. Rot and seams occurred in only 2 percent of the stems and appeared to occur randomly. Forks in the first 2.4 m of the tree bole also were rare (occurrence of 5 to 13 percent), but were more common in the second 2.4 m (22 to 68 percent). Species had a greater effect on stem quality than other factors. Northern red oak (Q. rubra) had the best quality followed by chestnut oak (Q. prinus). White oak (Q. alba) and black oak (Q. velutina) were significantly lower in quality followed by scarlet oak (Q. coccinea). Northern red oak had significantly better stem quality than white, black, or scarlet oak. Scarlet oak's poor quality was related to its inherent limb retention. Both fencing and harvesting treatment influenced stem density. In general, the higher the stand density, the better the quality of the stems.

Citation

Gottschalk, Kurt W. 1997. Stem quality of oak in 15-year-old stands: influence of species within harvesting treatment and fencing. In: Spiecker, H.; Rogers, R.; Somogyi, Z., comps. Advances in research in intermediate oak stands; 1997 July 27-30; Freiburg, Germany. Freiburg, Germany: Institute for Forest Growth, Albert-Ludwigs-University of Freiburg: 85-97.