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Table 3 Test statistics by surface fuel load (Mg ha−1), forest floor depth (cm), and seedling density (ha−1) for the 5-year frequency reburn randomized complete block repeated measures linear mixed model for the season and frequency of burn study in the Blue Mountain Ecoregion, Oregon, USA. Values for significant effects α = 0.05 are marked with an asterisk (*). df is the degrees of freedom for which the first number is the numerator and the second number is the denominator to compute the P value.

From: Long-Term Effects of Burn Season and Frequency on Ponderosa Pine Forest Fuels and Seedlings

 

Year

Treatmenta

Year × treatment

Response

F

P

df

F

P

df

F

P

df

1 h (Mg ha−1)

2.90

0.074

2, 25.4

5.77

0.007*

2, 35.6

1.90

0.141

4, 25.4

10 h (Mg ha−1)

1.46

0.248

2, 30

7.74

0.009*

2, 10

4.44

0.006*

4, 30

100 h (Mg ha−1)

8.19

0.002*

2, 27.3

13.81

0.001*

2, 11.4

3.56

0.019*

4, 27.3

1000 h (Mg ha−1)

2.65

0.087

2, 30.7

0.32

0.727

2, 17.3

2.75

0.046*

4, 30.7

Forest floor (cm)b

3.56

0.042*

2, 28.6

105.70

≤0.001*

2, 10.7

10.57

≤0.001

4, 28.6

Short seedlings (ha−1)c

6.50

0.006*

2, 23.2

0.57

0.580

2, 11.1

23.20

0.007*

4, 23.2

Tall seedlings (ha−1)d

2.81

0.081

2, 22.9

13.55

0.002*

2, 8.8

1.65

0.196

2, 22.9

  1. a Control (unburned), fall reburn, and spring reburn
  2. b Forest floor depth (cm)
  3. c Short seedlings defined as <0.4 m
  4. d Tall seedlings defined as >0.4 m and <1.37 m