Table 5. Results of two-way ANOVA testing the effect of the clipping treatment (C) and the harvesting seasons (H) (spring, summer, autumn) on relative ¹³C contents (%) of three fine-root classes.

Significant effects (P<0.05) are given in bold. (-: data not available).

Labelling season	Fine-root class	Clipping (C)			Harvesting season (H)			C x H
		df	F	P	df	F	P	df	F	P
Spring	New roots	1	0.05	0.833	2	5.75	0.012	2	0.30	0.747
	≤0.5 mm	1	9.08	0.008	2	2.91	0.080	2	0.71	0.504
	>0.5–1.0 mm	1	14.16	0.001	2	3.78	0.043	2	0.09	0.914
Summer	New roots	1	1.00	0.337	1	222.34	<0.001	1	0.36	0.559
	≤0.5 mm	1	2.09	0.172	1	8.99	0.010	1	0.74	0.405
	>0.5–1.0 mm	1	0.05	0.836	1	1.00	0.338	1	0.79	0.393
Autumn	New roots	1	0.31	0.598	-	-	-	-	-	-
	≤0.5 mm	1	<0.01	0.994	-	-	-	-	-	-
	>0.5–1.0 mm	1	25.76	0.002	-	-	-	-	-	-