Table 1.

Virulence of H. irregulare and H. occidentale measured as fungal growth in the spruce sapwood, and lesion expansion in the inner bark.

	Growth (mm)			Lesion (mm)
	2 w	4 w	6 w	2 w	4 w	6 w
H. occidentale	16.7 ± 12.6	42.0 ± 28.4	41.0 ± 36.0	7.7 ± 4.2	21.2 ± 16.6	28.2 ± 11.0
H. irregulare	23.8 ± 11.1	58.3 ± 7.6	62.5 ± 20.6	9.5 ± 7.6	11.0 ± 5.0	20.5 ± 7.2

Growth = Fungal growth in the sapwood, Lesion = lesion length in the inner bark, 2 w, 4 w and 6 w = 2, 4 and 6 weeks after inoculation (n = 3–5)^a.

^aNo significant difference between H. occidentale and H. irregulare (One-way ANOVA, P > 0.5) but a significant difference in growth in sapwood and expansion of lesions in the inner bark from two weeks compared to 4 and 6 weeks (Tukey test, P < 0.05).