Red Spruce Crop Tree Release After 20 Years in West Virginia

In 2005, a silvicultural restoration study was implemented to observe the response of individual red spruce to various percent basal area (BA; m2) removal treatments of competing hardwood species. These treatments consisted of four different basal area removals: control was 0 percent, low was about 33 percent, medium was about 67 percent, and high was about 100 percent around individual understory trees. Crop tree response was measured in 2007, 2010, 2013, and 2024. In each revisit, the diameter at breast height (DBH) and total height (TH) were collected. By 2016, trees in the three release treatments had a significantly greater increase in DBH and TH growth relative to controls. In 2024, all classes' average annual growth rates had increased. Growth of the trees in the removal treatments increased more than that of the controls. However, by 2024, there was no significant difference in the responses of the crop trees in the low and medium removal classes. Nonetheless, there was a significant difference between the growth of the high-treatment class and all other classes.