Stand Quality Management ofSouthern Hardwood Forests

Steve MeadowsUSDA Forest Service

Center for Bottomland Hardwoods Research

Stand Quality Management

If it’s a good tree, leave it!!

If it’s a poor tree, cut it!!

Preferred Growing Stock

Desirable Growing Stock

Acceptable Growing Stock

Cutting Stock

Cull Stock

Superior Poletimber Stock

Inferior Poletimber Stock

Thinning PrescriptionsStand Quality Management

Tree Class AccSupP AccNoPole DesSupP DesNoPole

Sawtimber

Preferred

Desirable

Acceptable

Cutting Stock

Cull Stock

Poletimber

Superior Pole

Inferior Pole

Step 1Conduct Timber Cruise

• Collect data on sample trees – species, dbh class, crown class, and tree class

• Calculate stand-level variables – trees per acre, basal area per acre, quadratic mean diameter, stocking percent, and tree class distribution

Step 1Conduct Timber Cruise

TREE CLASS TPA BA QMD

Preferred 8 17 20.0

Desirable 15 24 17.1

Acceptable 19 28 16.3

Superior Pole 12 7 10.1

Growing Stock 54 76 16.1

Cutting Stock 23 27 14.6

Cull Stock 7 10 15.5

Inferior Pole 36 13 8.1

Overburden 66 50 11.8

TOTAL 120 126 13.9

Step 2Make Appropriate Management Decision

• Do we manage the stand or regenerate the stand? – based on initial stand density and initial stand quality

• Do we thin the stand now or do nothing and allow it to grow until thinning is necessary? – based on initial density

Decision RuleManage or Regenerate?

MANAGE those stands in which:

• Stocking is at or above the C-15 lineAND

• The growing stock component accounts for at least 50 percent of total stand basal area

Decision RuleThin Now or Do Nothing?

• Decision is based solely on initial stand density

• THIN stands in which stocking is near, at, or above 100 percent

Step 3Select Appropriate Thinning Prescription

• Initial stand quality – tree class distribution

• Stage of stand development – length of time remaining in the rotation

Conceptual ModelStand Quality Management

STAGE OF STAND DEVELOPMENT

Early/Mid Late

INITIALMedium AccSupP AccNoPole

QUALITYHigh DesSupP DesNoPole

Tree Class Distribution

TREE CLASS BA BA % QMD

Preferred 17 13 20.0

Desirable 24 19 17.1

Acceptable 28 22 16.3

Superior Pole 7 6 10.1

Growing Stock 76 60 16.1

Cutting Stock 27 22 14.6

Cull Stock 10 8 15.5

Inferior Pole 13 10 8.1

Overburden 50 40 11.8

TOTAL 126 100 13.9

Conceptual ModelStand Quality Management

STAGE OF STAND DEVELOPMENT

Early/Mid Late

INITIALMedium AccSupP AccNoPole

QUALITYHigh DesSupP DesNoPole

Step 4Mark Stand for Thinning

• Remove ONLY those tree classes specified in the selected prescription

• No consideration for residual stand density• Timber marker should focus solely on

identifying trees in the tree classes specified for removal

• ALL trees in the specified tree classes should be removed

Step 5Plan Subsequent Thinnings

• Decision Rule – conduct subsequent thinnings when stocking again reaches near, at, or above 100 percent

• When stocking approaches 100 percent –conduct detailed timber cruise, as in Step 1

• Repeat process for each thinning until final harvest of the stand

Tree Class Distribution

TREE CLASS BA BA % QMD

Preferred 34 28 26.1

Desirable 29 23 23.1

Acceptable 41 33 22.2

Superior Pole 0 0 --

Growing Stock 104 84 23.7

Cutting Stock 17 14 16.4

Cull Stock 3 2 17.5

Inferior Pole 0 0 --

Overburden 20 16 16.8

TOTAL 124 100 22.0

Conceptual ModelStand Quality Management

STAGE OF STAND DEVELOPMENT

Early/Mid Late

INITIALMedium AccSupP AccNoPole

QUALITYHigh DesSupP DesNoPole