Response to crop-tree release by 7-year-old stems of Red Maple stump sprouts and Northern Red Oak advance reproduction.

This paper deals with crop-tree release sf two species typical of a fair site: red maple stump sprouts and northern red oak advance reproduction. A study was made to test the feasibility of doing a crop-tree release immediately after the canopy closed and crown classes could be distinguished. The study was made in a 7-year-old even-aged hardwood stand on the Fernow Experimental Forest near Parsons, West Virginia. A comparison of the following variables was made between released and control trees: total height growth, dbh growth, length of clear stem, and change in crown class. For the red maple sprouts, two crown classes were studied: dominants and codominants. For the red oak, three crown classes were studied: dominants, codominants, and intermediates. After the initial measurements, repeat measurements were made at 2 and 5 years following treatment. We conclude from this study that for the type of release, species, and site studied, release had no significant effect on height growth. The data indicate that diameter growth was favorably affected by release of the red maple stump sprouts, but release had no significant effect on the diameter growth of red oak advance reproduction. Length of clear stem was retarded during the 5-year period by release, but during this period red oak cleared up at a faster rate than red maple. Changes in 5-year crown class indicate that release had a minor effect on red oak, where crowns retrogressed heavily in dominance in both the release and control categories. However, released red maple codominants were definitely more dorminant than controls 5 years after release. Mortality was slight in all of the stem categories.