A New Tree Classification System for Southern Hardwoods

Abstract

A new tree classification system for southern hardwoods is described. The new system is based on the Putnam tree classification system, originally developed by Putnam et al., 1960, Management and inventory of southern hardwoods, Agriculture Handbook 181, US For. Serv., Washington, C, which consists of four tree classes: (1) preferred growing stock, (2) reserve growing stock, (3) cutting stock, and (4) cull stock. Tree classes under the Putnam system are used as a basis for planning partial cuttings and for developing marking rules in southern hardwood forests. However, there are critical problems associated with field use of this system: (1) the reserve growing stock class is too broad and poorly defined; (2) in most partial cutting operations, the timber marker must decide which reserve growing stock trees to cut and which ones to leave; (3) the timber marker must try to mark the stand to some prescribed, quantitative level of residual density; and (4) the timber marker often is forced to either leave low-quality trees or cut high-quality trees to maintain the target residual density uniformly across the stand. Overall stand quality often is compromised through use of the Putnam tree classification system and through strict adherence to the concept of stand density management. Our new tree classification system consists of five classes used only for sawtimber-sized trees: (1) preferred growing stock, (2) desirable growing stock, (3) acceptable growing stock, (4) cutting stock, and (5) cull stock; and two classes used only for poletimber-sized trees: (1) superior poletimber stock and (2) inferior poletimber stock. Data from one of our hardwood thinning studies are used to illustrate differences between the Putnam and the new tree classification systems. Potential uses and adaptations of the new tree classification system are described also.

Thinning: An Overview

“…Due to the variety of stand structures and management goals, many tree classification systems were developed. They evolved in time, increasing in complexity, as more criteria were included to increase accuracy and precision [7,8,11]. Typically, tree classification systems are grouped in two broad classes according to the stand structure and production goals.…”

“…Typically, tree classification systems are grouped in two broad classes according to the stand structure and production goals. One is directed towards pure even-aged stands with one main production (timber), for example, of kraft [10], of 1902 [10], English [12], of Assmann [2], Belgian [3], of Meadows and Skojac [11]. The other is directed to pure or mixed uneven-aged systems with one main production or several ones, for example, of Assmann [2], of Florence [8], of IUFRO [7], of Meadows [13] and of Perkey classification [14].…”

Silvicultural options for young bottomland oak-dominated plantations on former agricultural lands

“…To address these problems, we developed a new hardwood tree classification system for use in southern hardwood forests (Meadows and Skojac 2008). This system was General Technical Report SRS-263 designed for situations in which the production of high-quality sawtimber is the primary landowner objective.…”

“…Tree class distribution-The hardwood tree classification system developed by Meadows and Skojac (2008) can be used to compile a stand-level tree class distribution that represents the proportion of total stand basal area in each of the seven tree classes. The tree class distribution is a tool used to assess stand quality.…”

“…3. Use of the tree classification system developed by Meadows and Skojac (2008) as a tool to segregate trees into different classes of quality and suitability for achieving landowner objectives-this system can be used to identify trees to be retained and trees to be removed in any intermediate cutting operation.…”