Surface-check variation in boxed-heart square timber of sugi (Cryptomeria japonica) cultivars dried by the conventional kiln drying

Journal of Wood Science

Official Journal of the Japan Wood Research Society

Table 2 Tangential shrinkage (α _Tii), radial shrinkage (α _Rii), tangential/radial shrinkage ratio (α _Tii/α _Rii), basic density (BD), and the modulus of elasticity of green timber (MOE_GT)

Cultivar	Sample	α _Tii (%)		α _Rii (%)		α _Tii/α _Rii (%/%)		BD (kg/m³)		MOE_GT (GPa)
Cultivar	Sample	Mean	SD	Mean	SD	Mean	SD	Mean	SD	Mean	SD
Boka-sugi	B1	5.44	0.36	2.57	0.24	2.15	0.13	338	23	3.71	0.83
Boka-sugi	B4	6.19***	0.17	2.92***	0.19	2.13	0.12	328	12	6.01***	0.41
Aya-sugi	A1	6.43	0.20	2.45	0.23	2.68***	0.22	362	14	4.83	0.71
Aya-sugi	A4	6.76**	0.28	3.00***	0.21	2.27	0.20	403***	12	6.89***	0.59
Ryuunohige	R1	6.64	0.59	2.90	0.26	2.32***	0.26	356	19	8.94	0.72
Ryuunohige	R4	6.96	0.83	3.83***	0.24	1.82	0.20	376*	11	10.18***	0.61
Yabukuguri	Y1	6.66 b	0.26	2.16 d	0.14	3.15 a***	0.26	348 b	8	3.09 c	0.60
Yabukuguri	Y4	6.69 b	0.20	2.53 c***	0.19	2.67 b	0.18	363 a**	13	5.58 b***	0.63
Kumotooshi	K1	7.43 a	0.22	2.89 b	0.23	2.61 b***	0.25	356 ab	13	9.74 a	0.59
Kumotooshi	K4	7.26 a	0.27	3.22 a**	0.33	2.28 c	0.17	353 ab	12	10.35 a	0.63

There were significant differences among the samples Y1, Y4, K1, and K4 for α _Tii, α _Rii, α _Tii/α _Rii, and MOE_GT (P < 0.001), but not for BD (P = 0.051) using ANOVA. Different letters show significant differences using the Tukey–Kramer HSD test (P < 0.05)
Asterisks show significant differences between timber 1 and timber 4 within cultivars using a paired t test (***P < 0.001, **P < 0.01)