Cherrybark oak 7-year growth response in intermixed species, competitive neighborhoodsThis article is part of a larger document. View the larger document here.
In 2009, 6.5 acres on the University of Tennessee’s Cumberland Forest in Morgan County, TN, were identified for hardwood afforestation. Twenty-seven plots were planted in one of three species of hardwoods: yellow-poplar (Liriodendron tulipifera), black cherry (Prunus serotina), and sweetgum (Liquidambar styraciflua) at three spacings. Cherrybark oak (Quercus pagoda) was intermixed in these plantings such that each oak was completely surrounded by a competitor species. These unique, species-specific neighborhoods act on oak growth and development particular to variations in competitor crown architecture. After 7 years, oak survival ranged from 84.8 percent in 6-foot by 6-foot sweetgum plots to 100 percent survival in the 10-foot by 10-foot yellow-poplar plots. Oak diameter at breast height (d.b.h.) showed significant effects within spacing (p = 0.0002) and species (p = 0.0015), but not their interaction (p = 0.9110). Total mean cherrybark oak d.b.h. was 1.6 inches, ranging from 1.4 inches in the 6-foot by 6-foot yellow-poplar plots to 2.17 inches in the black cherry 10-foot by 10-foot plots. There were significant effects of spacing on cherrybark oak height growth (p = 0.0164) but no significant differences at the species level (p = 0.2410) or in the interaction of spacing and species (p = 0.7451). Comparisons of mean plot heights by spacing indicates significant cherrybark oak height differences between the 10-foot by 10-foot spacing (16.6 feet) and the 6-foot by 6-foot spacing (13.4 feet; p = 0.0091) but not between the 6-foot by 6-foot and 8-foot by 8-foot (14.9 feet; p = 0.3901) or the 8-foot by 8-foot and 10-foot by
10-foot spacings (p = 0.2905).