Table 2. The effects of interaction on the aboveground biomass of alfalfa and weeds.

Variable	Alfalfa		Weeds
	F	P	F	P
Y	4.750	<0.05	14.929	<0.001
T	0.861	0.431	29.695	<0.001
S	0.562	0.575	19.562	<0.001
Y × T	0.419	0.661	0.586	0.562
Y × S	0.221	0.803	1.045	0.362
T × S	0.204	0.934	8.807	<0.001
Y × T × S	0.058	0.994	0.150	0.962

Note:

Y, year; T, treatment; S, sampling time; Y × T, interaction between year and treatment; Y × S, interaction between year and sampling time; T × S, interaction between year and sampling time; Y × T × S, interaction between year, treatment and sampling time.