1. Landscape-Scale Thresholds
of Early Successional
Habitat
Reconciling Biodiversity, Public Perception, and
Timber Yield in Managed Forests
Susan Loeb, Beverly Collins, Laura DeWald, Jeremy Hyman,
Thomas Straka, Elizabeth Baldwin, Jonathan Brooks, Thomas Green

2. Early Successional Habitat
• Recently disturbed sites
• Sparse canopy
• Dominated by grasses, forbs, and shrubs
• Contain unique communities

7. Trani et al. 2001

8. Trani et al. 2001

9. Decline of ES
•Farm abandonment
•Urban/Suburban Development
•Suppression of natural disturbances
• Fire
• Beaver activity
• Flooding

10. Dettmers 2003

13. How can we best restore
early successional (ES) habitat?

14. Questions
1) Does opening size affect use,
abundance, or ecological relationships
of early successional species?
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15. Questions
2) Can changing the aggregation of
harvests more effectively increase
abundance of early successional
species at the stand and landscape
levels?
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16. Questions
2) Can changing the aggregation of
harvests more effectively increase
abundance of early successional
species at the stand and landscape
levels?
=

17. Questions
•If so, can we retain acceptable
timber yield?
•Will smaller cuts be more favorably
looked upon than larger cuts by the
public?

18. Great Smoky Mountains National Park

19. zzzzzzzzzzzzzzz
zzzzzzzz
Control
(no cutting) zzzzzzzzzzzz
20-25 ac
2-age harvest
zzzzzzzzzzzzzzz
zzzzzzzzzzzzzzz
zzzzzzzz5 1-ac harvests
Aggregated
5 1-ac harvests
Dispersed
2 9-ac harvests
Aggregated
2 9-ac harvests
Dispersed

20. zzzzzzzzzzzzzzz
zzzzzzzz
Control
(no cutting) zzzzzzzzzzzz
20-25 ac
2-age harvest
zzzzzzzzzzzzzzz
zzzzzzzzzzzzzzz
zzzzzzzz5 1-ac harvests
Aggregated
5 1-ac harvests
Dispersed
2 9-ac harvests
Aggregated
2 9-ac harvests
Dispersed
Installed 2016
Currently being
cut
Currently being
cut

21. Approaches To-Date
•Pre-treatment assessment of plants,
birds, and bats
•Effects of patch size on bats &
plants using existing ESH
•Initial studies of aggregation effects
on plants, bird, bats
•Harvesting economics modeling
•Public perception baseline info

22. Effects of Size on Biodiversity-
Plants
<3 ha 3-6 ha 6-10 ha
Green, in prep

23. Woody plant functional traits in
relation to edge
• No significant difference in the relationship
between seed size and distance from edge
between opening sizes (p = 0.659)
• No significant difference in relationship
between shade tolerance and distance from
edge by opening size (p = 0.248)

24. Effects of Opening Size on
Nocturnal Insect Abundance

25. Meaninsectabundance
Small Medium Large
Opening size
0
200
400
600
800
0
200
400
600
800
20152014
Brooks 2016
Small = 0.2-1.6 ha Medium = 2.1-5.6 ha Large = 6.2-18.5 ha
P > 0.10

26. Effects of Opening Size on Bat Activity
Meanbatactivity
Small Medium Large
Opening size
0
20
40
60
80
100
0
20
40
60
80
100
20152014
Brooks 2016
P > 0.10

27. Meanbatactivity
Interior Edge
Location
0
100
200
300
400
500
0
100
200
300
400
500
20152014
Positive Effects of Edge
P = 0.08

28. Size Effects on Birds

29. Common Name Total
Black-throated Green Warbler 76
Red-eyed Vireo 94
Hooded Warbler 68
Tufted Titmouse 68
Worm-eating Warbler 60
Black-and-white Warbler 55
Ovenbird 34
Scarlet Tanager 48
Indigo Bunting 6
Carolina Wren 25
American Crow 12
Northern Parula 16
Carolina Chickadee 23
Blue-headed Vireo 38
Blue-gray Gnatcatcher 18
Northern Cardinal 10
Blue Jay 16
Yellow-billed Cuckoo 6
Downy Woodpecker 3
Pileated Woodpecker 10
Eastern Wood-Pewee 5
White-breasted Nuthatch 14
Wood Thrush 9
Yellow-throated Warbler 36
Eastern Towhee 18
Red-bellied Woodpecker 13
American Redstart 0
Ruby-throated Hummingbird 2
Wild Turkey 0
American Robin 1
Rose Breasted Grosbeak 0
Broad-winged Hawk 7
Yellow-throated Vireo 0
Turkey Vulture 1
Mourning Dove 7
Red-breasted Nuthatch 0
American Goldfinch 1
Acadian Flycatcher 0
Brown Thrasher 0
White-Eyed Vireo 0
Cedar Waxwing 1
Red-tailed Hawk 0
Northern Flicker 2
Hairy Woodpecker 0
Ruffed Grouse 0
American Robin 2
Yellow-breasted Chat 14
Blackburnian Warbler 1
Eastern Phoebe 1
Great Crested Flycatcher 1
Black-throated Blue Warbler 7
Swainson's Warbler 5
Red Headed Woodpecker 2
Red: Edge &
Successional
Species
Bird Counts
in 1 Acre
Plots

30. Summer ‘16 – Initial ecosystem, plant, avian, insect, and bat
responses
open
edge
forest open
edge
Aggregation Effects – Preliminary Results

31. SoilMoisture
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
Open
Edge
Forest
6/06 6/13 6/21 6/27 7/04
SoilTemperature(C)
15
16
17
18
19
20
21
22
23
Center
Edge
Forest
6/06 6/13 6/21 6/27 7/04
Soil moisture
- Higher in forest
than edge and open
Soil temperature
- Highest in open,
lowest in forest
i.e., openings are hot
and dry compared to
the forest

32. SoilCO2Fluxumol/m
2
/s
2
4
6
8
10
Open
Edge
Forest
6/06 6/13 6/21 6/27 7/04
Soil respiration highest in forest, lower in edge, and lowest in open
- Contrary to hypothesis that cutting would increase soil respiration
- Suggests harvesting during hot, dry weather could partially
mitigate the increased soil respiration that typically occurs when
openings are created
Soil respiration
values similar to
values (ca. 4.5-
5.1 µmol m-2 s-
1) reported for
a forested area
at Coweeta in
June

33. NumberofVisitors
0
5
10
15
20
25
30
Aggregated
Disaggregated
Open Edge Forest
SpeciesRichness
0
2
4
6
8
10
12
14
- Significant (P<0.001)
interaction between
location and
aggregation;
- Insects higher in
aggregated forests
- no significant
difference between
treatments or among
locations
Diurnal Pollinating
Insects

34. Economic Consequences of Harvesting
Configurations – Costs

35. Economic Consequences of Harvesting
Configurations – Revenue
Economic Consequences of Harvesting
Configurations – Net Present Value

36. Net Present Value of Each Prescription
A B C D E
NPV -$9.37 -$106.76 $87.72 $81.71 $95.87
-$120.00
-$100.00
-$80.00
-$60.00
-$40.00
-$20.00
$0.00
$20.00
$40.00
$60.00
$80.00
$100.00
$120.00
Dollars
NPV
1 acre
Aggregated
1 acre
Dispersed
9 acre
Aggregated
9 acre
Dispersed 20 acre

37. Summary & Conclusions
• ESH patch size: little effect on plants & bats
• May need larger patches for ES birds
• ESH aggregation: still exploring
• Economic analysis suggests that larger,
aggregated patches provide the best return