Table 2. Results of ANCOVAs to test for clinal differentiation among invasive Ageratina adenophora populations along the elevational gradient.

Source of variation		Elevation		Garden		Elevation × Garden
Traits	df	F	P	F	p	F	p
Plant biomass*	1, 26	0.31	0.580	683.99	<0.001	0.41	0.527
Plant height	1, 26	6.68	0.016	5063.62	<0.001	0.026	0.874
Primary branch number*	1, 26	0.08	0.775	273.94	<0.001	0.06	0.809
Specific leaf area*	1, 26	0.24	0.627	0.22	<0.001	1.72	0.201
Leaf dry matter content	1, 26	0.53	0.820	6.16	<0.0199	3.17	0.868
Leaf area	1, 26	0.06	0.817	357.70	<0.001	0.87	0.358
Days to flower	1, 26	1.78	0.194	5717.07	<0.001	0.01	0.938
Number of capitula*	1,26	0.15	0.699	846.17	<0.001	0.05	0.820
Probability of flowering	1,13	3.20	0.097	-	-	-	-

Elevation of the home site of each population was used as a covariate, and garden as a factor. Please note that probability of flowering could only be tested for the low-elevation garden.

*These variables were log transformed, Leaf dry matter content was logit transformed, and Days to flower was square root transformed.