Table 3.

Effects of stand age, litter addition, and incubation time on soil P in experiment 2.

Soil P fractions	Effects
	Stand age (S)	Litter addition (L)	Incubation time (I)	S × L	S × I	L × I	S × L × I
Resin P	***	***	***	ns	***	***	ns
NaHCO3-Pi	***	***	***	ns	***	***	ns
NaHCO3-Po	***	***	***	ns	ns	**	ns
NaOH-Pi	***	***	***	ns	***	***	*
NaOH-Po	***	ns	***	ns	***	*	ns
HCl-Pi	***	ns	ns	ns	ns	ns	ns
Residual P	***	ns	ns	ns	ns	ns	ns

*, **, and *** indicate significance at p< 0.05, p< 0.01, and p< 0.001, respectively. P, phosphorus; ns, not significant.