An indicator for Criterion 2: Maintenance of Productive Capacity of Forest Ecosystems
What is the indicator and why is it important?
This indicator provides information fundamental to calculating the wood production capacity of existing forests and shows how much forest is potentially available for wood production, compared with total forest area. The availability and the capability of forest land to provide desired goods and services is a critical indicator of the balance of forest ecosystems relative to potential end uses. The multitemporal nature of the management objectives and planning guidelines for diverse U.S. owners, however, make it difficult to summarize the area of forest available for wood production in a single value at a single point in time, much less consistently over time. Within the context of this report, forest available for wood production will be defined as forest land not precluded by law or regulation from commercial harvesting of trees or timber land. In practice, the area available for wood production at any given time will always be a value less than total timber land. The amount of the area adjustment required to determine the actual availability of timber land will depend on the ownership mix and the management constraints in place at the time of analysis. This adjustment will affect all other indicators in Criterion 2 as well.
What does the indicator show?
Forest land in the United States, totaling 751 million acres, is nearly equally distributed between East and West, with 387 million acres in the East (North and South Regions) and 365 million acres in the West (Rocky Mountain, Pacific Coast, and Alaska Regions). Timber lands, including natural and seminatural stands and planted forests comprise the largest category of forest (fig. 10-1) with 514 million acres nationally; 368 million acres (72 percent) of this total is in the East and 146 million acres in the West. Planted forests currently comprise 12 percent (63 million acres) of all U.S. timber land and the area is increasing.
Planted forests are most common in the South where 45 million acres (72 percent) of all such forests in the United States occur. Planted forests are discussed in more detail in Indicator 2.12. The total area of timber land in the United States has been stable during the past 50 years with an overall loss of only 1 percent (fig. 10-2).
Ownership also plays a key role in the area available for U.S. wood production. Timber land is generally concentrated on private lands in the East (fig. 10-3) and public lands in the West. Overall, private timber lands account for 356 million acres, about 69 percent of all forest available for wood production in the United States.
Conifer forest types are fairly equally distributed between the
East and West and broadleaf types are dominant in the East
Private timber lands currently account for 91 percent of U.S. wood production, compared to 86 percent in 1952 (fig. 10-5). Although public ownerships have the benefit of very long-term tenure, recent public land policy shifts toward reducing the amount of wood harvested from public lands have contributed to increased pressure on private forests in the United States and increased imports to meet U.S. wood needs.
The notion of sustainability of forest available for wood production is linked to the demand for these forests for other uses. Natural events, and competing societal forces can also affect availability. Fire, weather, and insect and disease outbreaks can seriously affect supplies at any given time. Forest productivity can also be altered by pollution and human-caused degradation. Consumer preferences, recycling, and investments in the forestry sector and availability of workers also play a significant role in wood production. Sound institutional frameworks that provide continuous monitoring of critical aspects of forests are invaluable. Simply put, wood production relies on the existence of available forest land and all of the factors that influence the sustainability of that land.
What has changed since 2003?
Timber land has increased by 7 million acres in the East (2 percent) and 3 million acres in the West (2 percent) since 2003. Much of the increase came from the reclassification of previously marginal timber lands or areas, particularly in the mid-section of the country, that were previously classified as nonforest. This reclassification is more consistent with national standard definitions, and was applied to areas that tended to be privately owned.