Table 1 Sample sizes, range of stem diameters, and best fit equations for the relationships between stem diameter (in cm) and bark thickness (in mm) and stem diameter and the proportion of inner bark; n.s. indicates a non-significant relationship. Equations were not forced through the origin. Statistics (i.e., R², F, and P) for the best fit equations are given in Figures 1 and 4. Species are in order of their location along the pocosin-to-savanna gradient.

Species

N

Diameter range (cm)

Best fit equation

N

Diameter range (cm)

Best fit equation

Habitat

Pocosin

Acer rubrum

32

0.78 to 20.26

Y = 0.569 * X ^ 0.752

20

3.30 to 20.26

Y = −0.083 * ln(X) + 0.955

Nyssa biflora

32

2.07 to 40.59

Y = 0.693 * X ^ 0.934

29

2.75 to 40.59

n.s.

Liriodendron tulipifera

32

0.77 to 37.33

Y = 0.596 * X + 0.120

27

3.29 to 37.33

Y = 1.079 * X ^ −0.264

Quercus nigra

20

0.95 to 29.72

Y = 0.835 * X ^ 0.797

17

2.01 to 29.72

n.s.

Pinus serotina

34

1.87 to 45.22

Y = 2.038 * X ^ 0.649

34

1.87 to 45.22

Y = −0.091 * ln(X) + 0.404

Liquidambar styraciflua

30

1.05 to 35.60

Y = 1.105 * X ^ 0.840

27

2.35 to 35.60

n.s.

Savanna

Pinus palustris

34

1.79 to 40.62

Y = 3.005 * X ^ 0.471

33

2.23 to 40.62

Y = −0.100 * ln(X) + 0.448

Quercus marilandica

32

0.85 to 30.47

Y = 1.964 * X ^ 0.682

31

1.98 to 30.47

n.s.

Quercus laevis

32

1.18 to 37.63

Y = 0.686 * X + 2.658

30

2.55 to 37.63

Y = 0.737 * X ^ −0.216

Quercus margarettae

30

1.18 to 18.00

Y = 1.449 * X ^ 0.786

25

2.42 to 18.00

Y = 0.635 * X ^ −0.214

Quercus incana

26

0.74 to 22.19

Y = 1.721 * X ^ 0.741

23

2.34 to 22.19

Y = 0.575 * X ^ −0.136