Source: NORTHERN ARIZONA UNIVERSITY submitted to
INSECTS AS ECOLOGICAL INDICATORS FOR SOUTHWESTERN PONDEROSA PINE FORESTS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0193376
Grant No.
2002-35302-12711
Project No.
ARZZ-2002-02702
Proposal No.
2002-02702
Multistate No.
(N/A)
Program Code
51.2
Project Start Date
Sep 15, 2002
Project End Date
Sep 14, 2005
Grant Year
2002
Project Director
Wagner, M. R.
Recipient Organization
NORTHERN ARIZONA UNIVERSITY
(N/A)
FLAGSTAFF,AZ 86011
Performing Department
SCHOOL OF FORESTRY
Non Technical Summary
There is great concern among scientist and the general public that our forest be managed so as to keep them healthy. The assessment of whether a forest is healthy requires the measurement of many complex ecological variables. It is costly and difficult to measure the full complement of ecological variables that are used to measure forest health. Consequently, we are developing and testing the suitability of various parameters of insects as ecological indicators of forest health. Our experiments will assess the abundance, biodiversity, and potential indicator value of ground beetles and bark beetles across the full range of forest conditions that exist in the ponderosa pine forests of Arizona (restored, managed, burned, unmanaged). These experiments will allow us to both understand how insects respond to these conditions and also allow us to evaluate insects as indicators of forest health.
Animal Health Component
20%
Research Effort Categories
Basic
80%
Applied
20%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
1230612107050%
1233110107050%
Goals / Objectives
Assess whether the abundance, diversity, and community structure of carabids (Coleoptera:Carabidae) and bark beetles can be used to predict variation in ponderosa pine (Pinus ponderusa) under various management conditions. Compare the following suite of ecological characteristics among strands representing 2 levels of human management (thinned and unthinned), 2 levels of natural disturbance (burned and unburned), and 1 natural old growth condition. Ecological characteristics include: stand density/structure, net primary productivity, soil nitrogen transformation rate, microbial biomass, and soil respiratia, soil carbon:nitrogen ratio, tree growth efficiency, canopy water stress, foliar nitrogen concentration.
Project Methods
Approach consists of creating four 100 acre replicated treatment of each of the 5 treatments (20 sites total). Sites are randomly selected from all sites meeting the criteria for that treatment. Field assessments begin in 2003 and continue for 2 years.

Progress 09/15/02 to 09/14/05

Outputs
NON-TECHNICAL SUMMARY: There is great concern among scientist and the general public that our forest be managed so as to keep them healthy. The assessment of whether a forest is healthy requires the measurement of many complex ecological variables. It is costly and difficult to measure the full complement of ecological variables that are used to measure forest health. Consequently, we are developing and testing the suitability of various parameters of insects as ecological indicators of forest health. Our experiments assessed the abundance, biodiversity, and potential indicator value of ground beetles and bark beetles across the full range of forest conditions that exist in the ponderosa pine forests of Arizona (restored, managed, burned, unmanaged). These experiments allow us to both understand how insects respond to these conditions and also allow us to evaluate insects as indicators of forest health. Thinning with and without prescribed burning can have long-term effects on ponderosa pine water stress, growth, phloem thickness, resin flow, and bark beetle abundance. Low levels of tree mortality from bark beetles at our study sites suggest remarkable resistance of ponderosa pine in mid-elevation forests in northern Arizona, even at high tree densities. APPROACH Approach consists of creating four 100 acre replicated treatment of each of the 5 treatments (20 sites total). Sites are randomly selected from all sites meeting the criteria for that treatment. Field assessments were conducted in 2003 and 2004. We found that stands that had thinning or thinning plus burning treatments had low in situ annual rates of net N mineralization in the mineral soil than unmanaged stands. However, the high-severity wildfire had net N mineralization rates that were about 60% higher than unmanaged stands. Because of similarities in net N mineralization rates among treatments under laboratory conditions, we speculate that variation in in situ net N transformation rates among stands were due to differences in C inputs (thinned and thinned plus burned) and soil microclimate (wildfire) among the stands. The size of the soil microbial C and N pools generally declined with decreases in litterfall (highest in unmanaged, intermediate in thinned and thinned plus burned, and lowest in wildfire stands); however, in situ rates of net soil CO2 efflux did not follow this pattern. Our results contrast with some previous studies in southwestern ponderosa pine forests where restoration treatments (both thinning and thinning plus burning) increased net N transformation rates. We hypothesize that the dissimilarity in responses to treatments across studies is due to differences in the relative effect of these treatments on the bunchgrass understory; large increases in understory biomass following restoration treatments appear to result in increases in N cycling rates, while small changes in understory biomass following these treatments lead to reductions in N cycling rates. We recommend that restoration and fire-hazard reduction treatments be applied preferentially to stands that have low understory production.

Impacts
This research will help forest land managers and the general public understand how various forest treatments or conditions will affect various ecological processes that are used as measures of healthy forest ecosystems. Foresters will have better tools to measure and classify whether forests are in a healthy condition following the completion of this research.

Publications

  • Gaylord, M.L. 2004. Bark beetle and tree physiology seasonal patterns in northern Arizona. MS Thesis School of Forestry, Northern Arizona University, Flagstaff, AZ 110 pp
  • Stephens, S. Sky. 2004. Ant (Hymenoptera: Formicidae) functional groups: Bioindicators of forest health in northern Arizona ponderosa pine forests. MSc thesis. Northern Arizona University. 72 pp.
  • Zausen, G.L. 2005. Long-term effects of thinning and prescribed burning on ponderosa pine water stress and bark beetle resistance in northern Arizona. M.S. Thesis, School of Forestry, Northern Arizona University. Flagstaff, Arizona.
  • Zausen, G.L., T.E. Kolb, J.D. Bailey, and M.R. Wagner. 2005. Long-term impacts of thinning and prescribed burning on ponderosa pine physiology and bark beetle


Progress 01/01/04 to 12/31/04

Outputs
Five experimental treatments were completed to assess whether abundance, diversity and community structure of ground beetles and bark beetles can be used to predict ecological conditions for a range of ponderosa pine forest conditions. Additional; variables of understory vegetation,presence of exotic weeds, net primary productivity, soil carbon:nitrogen ratio, soil microbial biomass,soil respiration, net N transformation rate, leaf water potential, leaf nitrogen content, and tree resin flow were also collected. All data in year 2 of the project were collected on schedule and data analysis is underway.

Impacts
This research will help forest land managers and the general public understand how various forest treatments or conditions will affect various ecological processes that are used as measures of healthy forest ecosystems. Foresters will have better tools to measure and classify whether forests are in a healthy condition following the completion of this research.

Publications

  • Stephens, S. Sky. 2004. Ant (Hymenoptera: Formicidae) functional groups: Bioindicators of forest health in northern Arizona ponderosa pine forests. MSc thesis. Northern Arizona University. 72 pp.


Progress 01/01/03 to 12/31/03

Outputs
Five experimental treatments were nearly completed to assess whether abundance, diversity and community structure of ground beetles and bark beetles can be used to predict ecological conditions for a range of ponderosa pine forest conditions. Additional; variables of understory vegetation,presence of exotic weeds, net primary productivity, soil carbon:nitrogen ratio, soil microbial biomass,soil respiration, net N transformation rate, leaf water potential, leaf nitrogen content, and tree resin flow were also collected. All data in year 1 of the project were collected on schedule but no data analysis has been completed as of yet.

Impacts
This research will help forest land managers and the general public understand how various forest treatments or conditions will affect various ecological processes that are used as measures of healthy forest ecosystems. Foresters will have better tools to measure and classify whether forests are in a healthy condition following the completion of this research.

Publications

  • No publications reported this period