Aspen Delineation 

Project

By Ed Lorentzen, Science

Coordinator, BLM, California 

State Office

Background

The Aspen Delineation Project is 

a cooperative interagency effort 

involving the Bureau of Land 

Management (BLM), the U.S. 

Forest Service (USFS), and the 

California Department of Fish and 

Game to assess the extent, condition, history of treatment, and 

management options for quaking 

aspen (Populus tremuloides) in the 

Sierra Nevada and Warner Mountains. Aspen occurs in the montane 

zone of the Sierra Nevada–Cascade Range and is an important 

contributor to biodiversity in 

the region. There are concerns 

over an observed decline in the 

health and distribution of aspen 

stands throughout this area. Loss 

or potential loss of aspen can be 

attributed primarily to successional 

processes that occur in the absence 

of natural fire regimes and with 

excessive browsing by ungulates. 

These processes have occurred 

over the past 100 to 140 years. If 

unchecked, the probable result for 

most aspen stands is replacement 

by conifers. On the basis of current 

information, the long-term persistence of P. tremuloides is likely to 

require active management because 

of changes in fire regimes and 

browsing by livestock or wildlife.

The immediate objective of the 

Aspen Delineation Project is to 

promote the development and 

implementation of standardized 

aspen inventory and stand assessment protocols among cooperating 

land and resource management 

agencies in California. The ultimate goal is to provide agency 

managers with the information and 

tools they need to achieve longterm conservation objectives for 

P. tremuloides in the Sierra Nevada 

and Warner Mountains. Tasks associated with achieving these objectives include (1) identifying which 

government agencies in California 

have aspen stands or jurisdictions 

related to aspen, (2) determining 

what information agency personnel have about their stands, (3) 

documenting what kind of stand 

restoration projects have been 

undertaken, (4) understanding 

what resources are needed to deal 

with aspen management issues, (5) 

identifying the principal agency 

contacts on aspen issues, and (6) 

determining what needs to be done 

to ensure the long-term persistence 

of this species in California.

Discussion

Since its inception in 2002, the 

Aspen Delineation Project has 

sponsored many events and activities designed to provide agency 

personnel with information and 

tools that will enhance their ability to manage P. tremuloides. The 

2003 products and services include 

(1) sponsorship of a conference 

on Developing Tools for Aspen 

Management, which was held in 

Davis, California, in May 2003 

and attended by more than 70 

agency personnel and other interested parties; (2) production of a 

CD-ROM entitled “Protocol for 

Recording Aspen Location and 

Condition” (information available 

at http://www.blm.gov/nstc/library/

library.html); (3) field crew training 

of BLM personnel in the Alturas, 

Eagle Lake, and Surprise Field 

Offices concerning implementation of the standardized aspen 

inventory and stand assessment 

protocols and procedures for 

updating interagency data sets; (4) 

sponsorship of two field seminars 

(in Bishop and Alturas, California) 

to give BLM and USFS staff who 

are presently updating their land 

use plans an opportunity to discuss 

aspen management issues; and (5) 

production of an electronic aspen 

bibliographic database. The aspen 

bibliography that was developed in 

2003 is a preliminary product that 

will be annotated and expanded to 

include library documents that are 

not readily available in electronic 

format.

The Aspen Delineation Project 

work plan for 2004 includes the 

following planned events and activities: (1) sponsoring additional field 

seminars similar to those offered in 

Alturas and Bishop in 2003; 

(2) developing recommended 

protocols for monitoring aspen 

regeneration on range allotments; 

(3) expanding and annotating the 

aspen bibliography; (4) cosponsoring an aspen symposium in conjunction with the February 2004 

conference of the Western Section 

of the Wildlife Society (Rohnert 

Park, California); (5) reviewing 

protocol effectiveness over the last 

2 years and revising the protocol as 

needed to improve its effectiveness; 

(6) developing a data dictionary 

linked to the protocol to improve 

crew efficiency; (7) cooperating 

with the California Department 

of Fish and Game on mapping 

known aspen locations; and 

(8) providing field crew training, 

on request, to enhance the ability 

of agency personnel to perform 

rapid assessments of aspen stand 

locations and condition.

The 2004 field seminars focus 

on aspen management issues in 

the Central Sierra Nevada. The 

NO. 72 DATE 08/24/04

Range

Forestry

Resource Note 72

Page 1
targeted audience includes wildlife 

biologists, botanists, hydrologists, 

silviculturists, fuels treatment 

specialists, archaeologists, local 

nongovernmental organizations, 

and County Agriculture Extension agents. The next stages of 

bibliography development include 

identification of published literature not available in electronic 

format (Phase 2); development and 

implementation of a strategy for 

annotating records when abstracts 

or annotations are not available 

(Phase 3); and development and 

implementation of a strategy for 

identifying and retrieving “gray 

literature” (Phase 4). The annotation and expansion of the aspen 

bibliography is being funded 

primarily by the Rocky Mountain 

Elk Foundation, which became 

an active participant in the Aspen 

Delineation Project after the May 

2003 conference on Developing 

Tools for Aspen Management.

Conclusion

Managing aspen to ensure that it 

remains a significant component of 

montane ecosystems in the Sierra 

Nevada and Warner Mountains 

will require that agency personnel have access to accurate data 

concerning the status and trends 

of P. tremuloides stands within 

their jurisdictions, as well as a 

good understanding of long-term 

ecological processes. The Aspen 

Delineation Project was initiated 

to provide agency personnel with 

some of the information and tools 

they need to achieve long-term 

aspen conservation objectives. 

Although the focus of this project has been on California aspen 

management issues, some of the 

knowledge and products developed 

in conjunction with the Aspen 

Delineation Project may be transferable to other States and regions. 

Selected deliverables for the Aspen 

Delineation Project—including 

the “Protocol for Recording Aspen 

Location and Condition,” the 

preliminary Aspen Bibliography, 

2002 Summary Report, 2003 

Summary Report, and 2004 Work 

Plan—may be downloaded from 

the California-BLM Web site 

(http://www.ca.blm.gov/pa/biology/

index.html) or obtained by requesting such products from the contacts listed below.

Contact

David Burton, Principal 

 Investigator

Aspen Delineation Project

2070 Orange Drive

Penryn, CA 95663

Phone: 916-663-2574

Email: peregrines@prodigy.net

and

Ed Lorentzen, Science Coordinator

Bureau of Land Management

California State Office

2800 Cottage Way, Suite W-1834 

Sacramento, CA 95825 

Phone: 916-978-4646

Fax: 916-978-4657

Email: elorentz@ca.blm.gov

Range

Resource Note 72

Page 2

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