Research

Principle Investigator: Justin DeRose

Conventional silvicultural approaches to regenerating desired tree species may be reasonable in some forest types of the Interior West and Utah. Rapidly changing environments associated with the increasing severity and extent of disturbances like bark beetle outbreaks and wildfires have challenged the long-term maintenance of forest ecosystems. Alternative approaches to silvicultural regeneration methods, in combination with artificial regeneration approaches that may focus on off-site species or assisted migration are needed for many forest types. We study the effects of spatially and temporally variable variants of conventional silvicultural approaches that are aimed at better controlling the composition of the post-harvest overstory on the regenerating environment in arrangements that vary in space and over protracted harvest entries. For example, irregular strip shelterwood-with-reserves in non-serotinous lodgepole pine forest types is a modification of the highly conventional shelterwood system, but that improves our chances of regeneration success in the following ways: 1) protracted shelterwood cut, and final overstory removal allow monitoring of desired regeneration for many decades to ensure success, 2) spatial variability improves regeneration success as temperatures warm by increasing the area of suitable establishment, 3) protracted removal cut in combination with retention level creates the shaded environment to allow enrichment planting of species other than lodgepole pine that have been deemed suitable for future changing climate.

Principle Investigator(s): Scott B. Jones
Plant, Soils, and Climate

Research to support better understanding soil carbon, water, snow and climate dynamics was undertaken on the T.W. Daniel Experimental Forest. Replacement sensors to measure soil water content, matric potential and temperature were installed. New four-component precision radiometers were also deployed to help quantify surface energy balance. In addition, four snow lysimeters were installed. In 2009, surface mapping was performed using Lidar methods to quantify fine scale snow accumulation and melting across the four primary vegetation cover types. Based on this work, the Utah State University Soil Physics Laboratory developed instruments to measure snow melting rates and soil water transport. Sensors using heat pulse methods to measure soil thermal properties and soil water vectors were built and tested and then installed with the lysimeters, to be monitored over the next decade as part of Dr. Jones research. A data transmission tower along with a cosmic ray neutron probe tower (part of the COSMS network) are also installed at the site.

Principal Investigator(s): Justin DeRose

The response of forests to changing climate is largely unknown. While tree-level effects have been studied, very little attention has been given to the effect of changing stand dynamics. In this long-term study, we are taking advantage of the known disturbance history of the forest – a stand-replacing fire in 1903 – after which the current forest established. The current forest is composed of a mix of lodgepole pine, Engelmann spruce, subalpine fir, quaking aspen, Douglas-fir and limber pine. A large, fixed-area plot was installed in this mixed-conifer forest type on the T.W. Daniel Experimental Forest. On this plot every tree, live or dead, has been bored with an increment corer to reconstruct past stand dynamics using their tree-rings since the establishment of the trees after the 1903 fire. We will reconstruct stand density, and stage of stand development, and also use historical climate data to evaluate the relative effects of species, density, canopy position, and climate on tree- and stand-level growth. 

Principal Investigator(s): Ted Daniel, Justin DeRose

From 1947 through 1981 Doc Daniel and his students monitored cone-bearing trees and counted cone crops. This unprecedented data set was recently published as part of a global data set on masting trees Global Change Biology (Hacket-Pain et al. 2022).The data are housed in the MASTREEplus data base. The relationship between cone crop and cone depredation, mostly by red squirrels, has also been studied on the T.W. Daniel Experimental Forest.

Related Literature:

Hacket-Pain et al. 2022. MASTREE+: Time‐series of plant reproductive effort from six continents. Global Change Biology, 28:3066-3082. 

Principal investigator(s): Jame Long, Marcella Windmuller-Campione

In addition to being an excellent demonstration example for silvicultural approaches to regeneration Engelmann spruce in the Central Rocky Mountains, the spruce-fir treatments were designed as replicated blocks that will have been remeasured on a 5-year remeasurement interval since their inception in 2008, and will be measured in perpetuity. Replicate blocks of greater than 20 acres that include: single tree selection system; group selection systems, and; shelterwood-with-reserves systems were designed to monitor the effects of various approaches to silviculture on Engelmann spruce regeneration, and also to build resistance and resilience to potential spruce beetle outbreaks. We employ the Utah State University Forestry Club each time we conduct a remeasurement.

 

Related Literature:

Bentz, B. J., and A. S. Munson. 2000. Spruce beetle population suppression in northern Utah. Western Journal of Applied Forestry. 15(3):122–128. 

DeRose, R. J., and J. N. Long. 2014. Resistance and Resilience: A Conceptual Framework for Silviculture. Forest Science. 60(6):1205–1212. 

Windmuller-Campione, M. A., R. J. DeRose, and J. N. Long. 2021. Landscape-Scale Drivers of Resistance and Resilience to Bark Beetles: A Conceptual Susceptibility Model. Forests. 12(6):798.

Windmuller-Campione, M. A., D. H. Page, and J. N. Long. 2017. Does the Practice of Silviculture Build Resilience to the Spruce Beetle? A Case Study of Treated and Untreated Spruce-Fir Stands in Northern Utah. Journal of Forestry. 115(6):559–567.

Windmuller-Campione, A. M., and N. J. Long. 2015. If Long-Term Resistance to a Spruce Beetle Epidemic is Futile, Can Silvicultural Treatments Increase Resilience in Spruce-Fir Forests in the Central Rocky Mountains? Forests. 6(4).