Search
Browse by Subject
Contact Information

Northern Research Station
11 Campus Blvd., Suite 200
Newtown Square, PA 19073
(610) 557-4017
(610) 557-4132 TTY/TDD

You are here: NRS Home / Research Programs /Sustaining Forests / Understanding the ecological roles of natural disturbance / Designing Pest-Resistant Forest Landscapes: The Importance of Spatial Pattern.
Sustaining Forests

Designing Pest-Resistant Forest Landscapes: The Importance of Spatial Pattern

[photo:]  eastern spruce budworm (Choristoneura fumiferana Clemens).Research Issue

Defoliating insects damage millions of acres of forested land annually in the United States.  The balance of evidence suggests forest insect outbreaks today are more damaging than ever because of changes in forest composition and structure induced by fire suppression and post-harvest proliferation of tree species intolerant to herbivory.  Our central hypothesis is that landscape connectivity of acceptable host types increases defoliator population connectivity, altering the dynamics and spatial structure of defoliator populations, and thus increasing forest susceptibility to insect pest damage.   


[photo:] forest tent caterpillar (Malacosoma disstria Hübner)Our Research

We address the above hypothesis by examining spatial and temporal components of forest-insect dynamics for two major insect pests with very different life histories – spruce budworm and forest tent caterpillar – in response to regionally varying forest landscape structures.  Specifically, we are investigating: (1) spatial effects of forest landscape structure on defoliation damage, using a combination of molecular genetic techniques, remote sensing, and multi-scale pattern analyses; (2) temporal effects of changes in forest landscape structure on defoliation damage using dendrochronology, air photos, and aerial survey data; and (3) spatio-temporal implications of different land use policies on outbreak dynamics via landscape-level modeling with LANDIS - a spatially explicit forest simulator.  We are contrasting insect disturbance patterns, impacts, and landscape responses within a 2 million ha “experimental” landscape at the U.S.- Canadian border, containing wilderness plus two contrasting patterns of harvesting (coarse vs. fine).

Expected Outcomes

Our research will provide a general approach to understanding insect-forest-landscape interactions, allowing forest managers to strategically deploy resources to reduce forest susceptibility to defoliating insects.

Research Results

Anderson, D.P.; Sturtevant, B.R.. 2011.  Pattern analysis of spruce budworm (Choristoneura fumiferana) dispersal.  Ecography 34: 488-497.

James, P.M.A; Fortin, M.J.; Sturtevant, B.R.; Fall, A.; Kneeshaw, D. 2011. Modelling spatial interactions among fire, spruce budworm, and logging in the boreal forest.  Ecosystems 14: 60–75.

James, P.M.A.; Sturtevant, B.R.; Townsend, P.A.; Wolter, P.T.; Fortin, M.J.. 2011. Two-dimensional wavelet analysis of spruce budworm host basal area in the Border Lakes landscape.  Ecological Applications 21: 2197–2209

Wolter, Peter T.; P A Townsend; B R Sturtevant. 2009 Estimation of forest structural parameters using 5 and 10 meter SPOT-5 satellite data. Remote Sensing of Environment 113: 2019-2036.

Wolter, P.T.; Townsend, P.A.; Sturtevant, B.R.; Kingdon, C.C. . 2008. Remote sensing of the distribution and abundance of host species for spruce budworm in Northern Minnesota and Ontario. Remote Sensing of Environment 112: 3971-3982.

Research Participants

Principal Investigator

Research Partners

Last Modified: 12/12/2016

Related IAES Research
Special Application

LANDIS - LANDIS is designed to model forest succession, disturbance (including fire, wind, harvesting, insects, global change), and seed dispersal across large (>1 million ha) landscapes. LANDIS represents landscapes as a grid of cells and tracks age cohorts of each species (presence/absence or biomass) rather than individual trees. LANDIS simulates distinct ecological processes, allowing complex interactions to play out as emergent properties of the simulation.