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Source. Adapted from Coile (1952) and Walker (1958)

Source. Adapted from Coile (1952) and Walker (1958)

Philip Wakeley, a long-time forest researcher in the South, developed the five-year intercept method for ascertaining future height growth of southern pines. The technique assumes that, once they reach breast height, trees of a given species continue growing at comparable rates for the following five years. It also assumes this is so for a wide range of plantation spacing and on comparable sites.

Variation by Species

SI varies dramatically by species. Thus, slash pine grows faster than longleaf pine for the first 25 years on most sites. Similarly, Virginia pine has a higher SI rating than shortleaf pine where the two species are associated. Typical SI ratings for other southern trees growing on similar sites range like this: Atlantic white-cedar, 45 to 75; Virginia pine, 65 to 77; pond pine, 31 to 76; white pine, 80 to 85 in the Appalachians; sweetgum in the bottomlands, 80 to 120; oaks (white and black) in the Piedmont, 70; loblolly pine, 50 to 120; and chestnut oak in the Southern Appalachian Mountains, 58.

Plantation Establishment

Artificial regeneration usually involves planting seedlings produced in intensively managed nurseries. At state, federal, and private nurseries, cones and hardwood fruits are dried, the seeds are extracted (usually by drying), and planted in beds.

Planting is done where and when natural seeding is not available to hasten stand regeneration, to introduce genetically superior trees, and to more likely assure even stocking of the new forest. Planting should be done promptly on harvest of the earlier stand or on seedbed preparation by machinery or by fire, lest broadleaf brush and undesirable hardwood sprouts encroach. Even with prompt planting of healthy 1-year-old nursery stock, protection from undesirable hardwood competition may be essential.6

Figure 5.6 Believed to be the oldest pine tree plantation in the South, these loblolly and shortleaf pines were lifted from nearby woods in 1873. The seedlings, spaced 20x20 feet, by age 90 years had grown to an average dbh of 18 inches (loblolly) and 17 inches (shortleaf) and had produced 21,000 board feet per acre.

Figure 5.6 Believed to be the oldest pine tree plantation in the South, these loblolly and shortleaf pines were lifted from nearby woods in 1873. The seedlings, spaced 20x20 feet, by age 90 years had grown to an average dbh of 18 inches (loblolly) and 17 inches (shortleaf) and had produced 21,000 board feet per acre.

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