Whitebark Pine Stand Conditions after Mountain Pine Beetle Outbreaks in Idaho, Wyoming and Montana

Kendra Schotzko1, Stephen Cook1, Carl Jørgensen2, Sandy Kegley3, John Schwandt3, Laura Lazarus2, and Jim Hoffman2

1University of Idaho, Moscow, ID 2Forest Health Protection, Boise, ID 3Forest Health Protection, Coeur d’Alene, ID

v

IntroductionWhitebark pine has a large natural range but is in serious jeopardy especially in the Intermountain West. Recent aerial detection surveys have documented increasing whitebark pine mortality throughout central Idaho.

Whitebark pine is a keystone species of high elevation ecosystems throughout western North America. It is crucial in watershed stabilization and creating habitats that support a wide diversity of plants and animals. The old gnarled relics in remote timberline areas provide important aesthetic values. (Schwandt 2006, Tomback et al. 2001)

Whitebark pine is currently at risk in much of its natural range due to a combination of white pine blister rust, forest succession, and recent outbreaks of mountain pine beetle. (Gibson et al. 2008, Keane et al. 2002).

ObjectiveThe primary goal is to obtain information that will be used to make recommendations and set priorities regarding restoration of whitebark pine in Central Idaho and adjacent areas in Wyoming and Montana.

This poster focuses on three objectives key to this goal:• Quantify dead and remaining

live mature whitebark pine• Assess health of whitebark pine

regeneration in these stands• Determine probable stand

trajectory by recording abundance of other species

Results ConclusionsDuring our first field season we visited 20 different sites (Figure 1) to assess the abundance and condition of mature trees in mountain pine beetle affected areas, in addition to the abundance and condition of regeneration in these areas.

Our results (Figure 2) indicate substantial mortality of mature whitebark pine in the majority of sites measured, largely due to mountain pine beetle.

Our results (Figure 2) also suggest a widespread decrease in whitebark pine regeneration relative to subalpine fir.

Future DirectionAdditional sites will be sampled in Idaho, Montana, Wyoming and Nevada. A summary report for each site will describe current whitebark pine condition following mountain pine beetle outbreaks as well as condition of other species.

Results will be used to make recommendations regarding restoration activities and priorities for restoration. Data will also be used to develop loss prediction models for whitebark pine.

Additionally, tests involving reproduction pests will be initiated under laboratory conditions to examine the acceptability and suitability of whitebark pine cones to reproduction pests.

AcknowledgementsThis project was funded by the USDA-Forest Service, Evaluation Monitoring Program.

Chad Nelson (Forest Health Protection, Boise, ID), Phil Mocettini (Forest Health Protection, Boise, ID), and Paul Zambino (Forest Health Protection, Coeur d’Alene, ID).

Deb Taylor, Jim Robertson, and the many others at the regional Forest Service offices in the Idaho Panhandle National Forest, Helena National Forest, Salmon-Challis National Forest, Sawtooth National Forest, Sawtooth National Recreation Area, and the Caribou-Targhee National Forest.

William Sweeney and Colleen Makar, University of Idaho, Moscow, ID

ReferencesGibson, K.; Skov, K; Kegley, S; Jorgensen, C; Smith, S; and Witcosky, W. 2008. Mountain pine beetle impacts in high-

elevation five-needle pines: current trends and challenges. USDA Forest Service, Forest Health Protection Report R1-08-020.

Keane, R.E., Ryan, K.C., Veblen, T.T., Allen, C.D., Logan, J.A., and Hawkes, B. 2002. Cascading effects of fire exclusion in Rocky Mountain ecosystems. In: Baron, J.S. (Ed.), Rocky Mountain Futures: An Ecological Perspective. Island Press.

Schwandt, J.W. 2006. Whitebark Pine in Peril: A case for restoration. USDA Forest Service, Report R1-06-28, Missoula, Montana.

Tomback, D.F., Arno, S.F., Keane, R.E. 2001. The compelling case for management intervention. In: Tomback, D.F., Arno, S.F., Keane, R.E. (Eds.), Whitebark Pine Communities: Ecology and Restoration. Island Press.

MethodsAreas in Central Idaho and adjacent areas in Wyoming and Montana where recent mountain pine beetle outbreaks have occurred were identified from past ADS, local specialists, or other surveys.

These areas were sampled using modified FINDITS protocols that use variable radius plots for mature trees and fixed area plots for regeneration. Data collected included: tree species, diameter at breast height, condition.

WBP-LIVEWBP-DEADSAF-LIVESAF-DEADLPP-LIVELPP-DEADOTHER-LIVEOTHER-DEAD

WBP1-RustWBP2-RustWBP3-RustWBP1-No RustWBP2-No RustWBP3-No RustSAF1SAF2SAF3LPP1LPP2LPP3OTHER1OTHER2OTHER3

Figure 2. Number of mature tree species (top row) and regenerative tree species(bottom row) at three representative sites. Species codes as in Figure 1. Thenumbers next to the regeneration species indicates the size class, where 1 = treesless than 6 inches tall, 2 = trees between 6 inches and 4.5 feet tall, and 3 = treestaller than 4.5 feet with DBH less than 5 inches.

A B C

0

10

20

30

40

50

60

70

80

Nu

mb

er

of

Tre

es

wit

h D

BH

> 5

Inch

es WBP-LIVE WBP-DEAD SAF-LIVE SAF-DEAD

LPP-LIVE LPP-DEAD OTHER-LIVE OTHER-DEAD

0

200

400

600

800

1000

1200

1400N

um

be

r o

f Tr

ee

s w

ith

DB

H <

5 In

che

s

WBP-Rust WBP-No Rust SAF LPP OTHER

Idaho Panhandle

NF

Helena NF

Caribou-Targhee NF & Jedediah Smith Wilderness

Salmon-Challis NF

Sawtooth NF & Sawtooth National Recreation Area

Figure 1. Relative abundance of mature tree species (top graph) and regenerative tree species (bottomgraph) at all 20 sites, grouped by geographic area. Species codes: WBP = whitebark pine, SAF = subalpinefir, LPP = lodgepole pine, and Other = all other species.