Characterization of stem volume and form tradeoffs in a northern red oak (Quercus rubra) breeding population in early stages of selection

Table 2 Individual (h²_i) and family mean heritability (h²_f) and the standard errors for each trait across sites. Equations for the heritability calculations and standard errors are provided in the text

	Height^a	DBH	Volume	Forking^b	Branch angle^c	Sweep^d	Branch retention^e
h²i ± SE	0.18 ± 0.06	0.27 ± 0.07	0.26 ± 0.07	0.16 ± 0.08	0.53 ± 0.20	0.35 ± 0.08	0.20 ± 0.09
h²f ± SE	0.37 ± 0.10	0.58 ± 0.08	0.50 ± 0.11	0.49 ± 0.12	0.73 ± 0.18	0.66 ± 0.13	0.50 ± 0.14

^a Tree height, diameter at breast height (DBH), and volume (D²H) were calculated after 12 or 13 growing seasons
^b Presence or absence of a 3.7-m log without a fork (forking), estimated across two sites only (115 and 119)
^c Average angle of branches below 3.7 m measured adaxially was greater than ( +) or less than ( −) 45°
^d A genotype showing an off-center deviation of more than 1/3 of the stem diameter in the bottom 3.7 m of stem or deviation > ¼ stem diameter in two or more planes was scored as ( +) showing sweep
^e Presence ( +) or absence of three or more branches with diameter greater than 2.5 cm on the bottom 3.7 m of the main stem

ISSN: 1297-966X