Litter to glitter: promoting herbaceous groundcover and diversity in mid-southern USA oak forests using canopy disturbance and fire

Fire Ecology

Table 2 Overall (2008 to 2016) and end-result (2016) ANCOVA and ANOVA model results for groundcover variables observed within oak woodland and savanna restoration experiments at CWMA (Catoosa Wildlife Management Area, Cumberland County, Tennessee, USA), GRGL (Green River Game Lands, Polk County, North Carolina, USA), and LBL (Land Between the Lakes National Recreation Area, Stewart County, Tennessee, USA). Richness and diversity (Shannon-Wiener Index) refer to the herbaceous community. Boldface values indicates significant (α = 0.05) and interpretable effects. Model df calculated using Kenward-Roger adjustment

Site	Groundcover variable	Overall model (2008 to 2016)						End result (2016)
		Treatment		Year		Treatment × Year		Treatment
		F	P	F	P	F	P	F	P
CWMA	Graminoid	5.1	0.051	59.2	<0.001	9.7	<0.001	5.9	0.040
	Forb	6.7	0.029	62.0	<0.001	7.7	<0.001	9.6	0.015
	Richness	6.3	0.034	70.1	<0.001	9.5	<0.001	8.8	0.017
	Diversity	7.3	0.025	81.0	<0.001	8.3	<0.001	6.7	0.031
	Woody	26.6	0.001	144.8	<0.001	10.5	<0.001	31.9	0.001
	Litter	84.6	<0.001	109.6	<0.001	6.7	<0.001	119.8	<0.001
	Debris	1.5	0.334	22.5	<0.001	3.7	<0.001	5.9	0.039
	Bare	27.6	<0.001	37.1	<0.001	6.8	<0.001	0.4	0.831
GRGL	Graminoid	44.0	<0.001	93.8	<0.001	16.4	<0.001	11.4	<0.001
	Forb	15.3	<0.001	34.9	<0.001	5.8	<0.001	4.6	0.002
	Richness	34.3	<0.001	64.8	<0.001	8.0	<0.001	18.5	<0.001
	Diversity	48.7	<0.001	71.1	<0.001	9.6	<0.001	23.3	<0.001
	Woody	21.4	<0.001	9.0	<0.001	8.6	<0.001	19.6	<0.001
	Litter	29.7	<0.001	36.7	<0.001	10.3	<0.001	43.6	<0.001
	Debris	7.1	<0.001	12.4	<0.001	3.7	<0.001	1.4	0.243
	Bare	16.9	<0.001	53.4	<0.001	9.7	<0.001	10.9	<0.001
LBL	Graminoid	7.8	0.009	13.3	<0.001	6.5	<0.001	5.0	0.030
	Forb	1.3	0.343	24.3	<0.001	3.2	<0.001	2.3	0.160
	Richness	3.3	0.079	30.2	<0.001	6.0	<0.001	2.7	0.118
	Diversity	3.8	0.059	30.6	<0.001	5.6	<0.001	4.3	0.044
	Woody	6.9	0.012	66.7	<0.001	6.4	<0.001	4.4	0.041
	Litter	25.7	<0.001	55.8	<0.001	8.1	<0.001	14.5	0.001
	Debris	7.4	0.012	12.9	<0.001	1.9	0.017	4.6	0.037
	Bare	3.6	0.065	34.8	<0.001	3.3	<0.001	0.9	0.474