KNFMerchantability.pdf

KNF SUPPLEMENT 2409.12-06-1

2409.12,10 Effective 03/01/06

FOREST SERVICE HANDBOOK

PINEVILLE, LOUISIANA

TITLE: 2409.12- TIMBER CRUISING HANDBOOK

KNF Supplement No 2409.12-06-1

Effective March 1, 2006

POSTING NOTICE. Supplements are numbered consecutively by Handbook number and calendar year. Post by document name. Remove entire document and replace with this supplement.

Document Name

Digest:

This supplement changes merchantability specifications for reference height measurement (Chapter 10, Principles of Measuring Trees).

MARGRETT L. BOLEY

Forest Supervisor

14 Measurements of the Tree - Volume Estimation

Merchantability of Trees:

1. Softwood Sawtimber. Must have a minimum DBH of 11.0 inches and a minimum merchantable length of 12’. Sawtimber will require two height measurements:

-- A. Merchantability (height #1) -- B. Point-on-stem (height #2)

A. Merchantable height is sometimes called reference height:

(1) A minimum top diameter outside bark (DOB) of 7.0 inches (6.0 inches inside bark);

OR

(2) The point on the upper stem at which excessive taper occurs.

“Excessive taper” is a subjective term and refers to a drastic change in the characteristics of the upper stem of the tree. The two primary features generally associated with excessive taper are stem defect and the presence of limiting whorls:

(a) Stem defect. For example, mechanical damage or disease (fusiform rust) which has penetrated well past the bark and into the wood.

(b) A limiting whorl. A limiting whorl is branches, at least one inch in diameter, radiating from three faces (i.e., more than two faces) and situated within a 12-inch vertical span, where diameter sum equals the outside stem diameter at that point on the stem. The term “branch” shall mean live or dead branches, with or without bark, protruding from the main stem sufficiently sold enough to estimate the branch diameter.

(c) NOTE: If a usable 8-foot section or longer occurs above either (a) or

(b), take the merchantable height to the top of this section. A usable section is one not having the characteristics of (a) or (b) and not limited by diameter.

B. Point-on-Stem is height #2.

(1) A minimum diameter of 7.0 inches DOB, which should be reasonably straight and sound.

It is acceptable to have height #1 and height #2 equal.

2. Small Roundwood – Softwood. Must have a minimum DBH of 5.0 inches and a minimum merchantable length of 10 feet.

A. The upper limit of merchantability is defined as:

(1) 4.0 inches DOB, OR

(2) That point at which stem deformity prevents utilization. If at least a 5-foot section occurs above this point, take the merchantable height to the top of this section. A usable section is one that is reasonably straight and sound and whose small end diameter equals or exceeds 4.0 inches outside bark.

3. Hardwood Sawtimber. Must have a minimum DBH of 13.0 inches and a minimum merchantable length of 12 feet. Sawtimber will require two height measurements:

-- A. Merchantability (height #1) -- B. Point-on-stem (height #2)

A. Merchantable height (sometimes called reference height)

(1) A minimum top diameter out side bark of 11.0 inches

OR

(2) The point at which the tree breaks into forks containing no merchantable sawlog product

OR

(3) A limiting whorl. A limiting whorl is one or more live limbs occurring within a vertical span of 12-inches, the sum of whose diameters equals the stem outside stem diameter at that point

OR

(4) A stem deformity.

NOTE: If a usable 8-foot section or longer occurs above either (3) or (4), take the merchantable height to the top of this section. A usable section is one not having the characteristics of (3) or (4) and not limited by diameter.

B. Point-on-stem is height #2.

(1) A minimum top diameter of 9.0 inches DOB, which should be reasonably straight and sound.

4. Small Roundwood – Hardwood. Must have a minimum DBH of 6.0 inches and a minimum merchantable length of 10 feet.

A. The upper limit of merchantability is defined as:

(1) 4.0 inches DOB, OR

(2) That point at which stem deformity prevents utilization. If at least a 5-foot section occurs above this point, take the merchantable height to the top of this section. A usable section is one that is reasonably straight and sound and whose small end diameter equals or exceeds 4.0 inches outside bark.

5. Forked Trees: The proper method of measuring forked trees may be found in R8 2409.12, Section 14.12b. When the fork is below DBH, count and measure as two separate trees. When the fork is above DBH, measure as one tree and measure the longest utilizable fork.

6. Stump Height. Measure reference height from the high-ground side of the tree to the specified height(s). The volume equations have a standard stump height built in. For contractual purposes, stump heights are: Sawtimber: 12"; pine roundwood: 6"; and hardwood roundwood: 8".

Other:

Merchantability Specifications as they pertain to the timber sale contract:

Minimum Tree: The smallest tree in a product class that will be measured and designated for sale. In our case, for pine sawtimber tree it would be 11" DBH with a merchantable height of 12'.

Minimum Piece: The smallest piece of a tree in a given product class that must be utilized in the timber sale contract, section AT2. For pine sawtimber, any portion of a tree with a length of 12' and a small end diameter of 6.0" DIB.

For sale prep and tree measurement, see the Exhibit #1 below:

Exhibit #1 Minimum Tree Specifications

Species Product DBH Merchant. Length/Top SYP Pine Sawtimber 11.0 12' to 7.0" DOB 30% Sound Mix Hdwd Hardwood Saw 13.0 12' to 11.0" DOB 30% Sound SWD Pine Roundw'd 5.0 10' to 4" DOB N/A Hdwd Hwd Roundw'd 6.0 10' to 4" DOB N/A

For timber sale contract preparation, see Exhibit #2 below:

Exhibit #1 Minimum Specifications: -AT2

No of Minimum

Species Product DBH - Pieces per Tree

Length| DIB Net Scale

SYP Sawtimber 11 1 12' | 6.0" 30% Softwood -Other Pulpwood 5 1 10' | 3.5" N/A HDWD Sawtimber 13 1 12' | 10" 30% Softwood -Hdwd Pulpwood 6 1 10' | 3.5" N/A