Node frequency alters stem biomechanics and hydraulics in four deciduous woody species

Journal of Wood Science

Official Journal of the Japan Wood Research Society

Table 2 Means (± 1 SE) for anatomical traits measured within nodes and internodes of four species, including mean and maximum vessel diameters from xylem in the internode, from adjacent to the node gap in the node, and from opposite of the node gap in the node

	Juglans californica	Populus trichocarpa	Quercus robur	Rhus aromatica
Mean vessel diameter (µm)
Internode	34.22 ± 3.17	20.29 ± 1.39	21.77 ± 1.12	19.03 ± 2.88
Node
Adjacent node gap	29.95 ± 1.59	18.37 ± 0.65	22.53 ± 1.00	21.55 ± 1.26
Opposite node gap	33.19 ± 2.65	20.62 ± 1.05*	22.90 ± 1.12	21.98 ± 3.10
Maximum vessel diameter (µm)
Internode	71.72 ± 6.41	42.03 ± 1.49	50.74 ± 2.78	58.44 ± 4.30
Node
Adjacent node gap	66.56 ± 5.53	40.59 ± 1.90	53.60 ± 4.41	54.55 ± 3.72
Opposite node gap	76.60 ± 9.26	44.22 ± 1.69	54.42 ± 5.04	61.25 ± 3.51**

There were no significant differences in vessel diameters between nodes and internodes (P > 0.05 for all). Within the node, two species displayed differences in vessel diameters adjacent to and opposite from the node gap (* P = 0.03, ** P < 0.001)