Table 2. Carbon and nitrogen concentrations of shoots and roots of plants grown at aCO₂ (400 µmol mol⁻¹) and eCO₂ (600 µmol mol⁻¹) with and without root damaging insects (RD).

CO2 concentration(µmol mol−1)	Herbivory	Leaf N (mg g−1)	Leaf C1 (mg g−1)	Root N (mg g−1)	Root C (mg g−1)
400	Absent	a 30.7±6.3	477.0±97.3	12.8±2.6	470.7±96.1
	Present	a 28.7±5.9	479.1±97.8	12.6±2.6	473.6±96.7
600	Absent	b 22.0±4.5	480.0±98.0	12.4±2.5	467.9±95.5
	Present	b 23.4±4.8	480.6±98.1	13.3±2.7	470.3±96.0
CO2		F1,4 = 12.02	F1,4 = 0.15	F1,4 = 0.30	F1,4 = 0.18
		P  = 0.026	P = 0.716	P = 0.611	P = 0.697
RD		F1,88 = 0.15	F1,88 = 0.07	F1,88 = 0.19	F1,88 = 1.37
		P = 0.701	P = 0.790	P = 0.667	P = 0.244
CO2 × RD		F1,88 = 4.82	F1,88 = 0.11	F1,88 = 2.32	F1,88 = 0.01
		P  = 0.031	P = 0.746	P = 0.132	P = 0.907

Mean values ± S.E shown, N = 24. Significant effects indicated in bold. Lowercase superscript letters indicates significant differences (P<0.05) between treatments.

¹Arcsine square root transformation applied.