Treesearch

Accounting for externalities generated by fire spread is necessary for managing fire risk on landscapes with multiple owners. In this paper, we determine the optimal management of a synthetic landscape parameterized to represent the ecological conditions of Douglas-fir (Pseudotsuga menziesii) plantations in southwest Oregon. The problem is formulated as a dynamic game, where each agent maximizes their own objective without considering the welfare of the other agents. We demonstrate a method for incorporating spatial information and externalities into a dynamic optimization process. A...

Knowledge of the spatiotemporal variability of abundance and vital rates is essential to the conservation of wildlife populations. In Pacific Northwest forests, previous small mammal research has focused on estimating abundance; few studies have focused on vital rates. We used robust design temporal symmetry models and livetrapping data collected 2011–2016 at nine sites to estimate apparent annual survival, population growth rate, andrecruitment of Humboldt’s flying squirrels (Glaucomys oregonensis) and Townsend’s chipmunks (Neotamias townsendii) in a late-successional forest of the...

Background: Tree species in the genus Cedrela P. Browne are threatened by timber overexploitation across theNeotropics. Genetic identification of processed timber can be used to supplement wood anatomy to assist in thetaxonomic and source validation of protected species and populations of Cedrela. However, few genetic resourcesexist that enable both species and source identification of Cedrela timber products. We developed several ‘omicresources including a leaf transcriptome, organelle genome (cpDNA), and diagnostic single nucleotide polymorphisms(SNPs) that may assist the classification...

The 2011–2014 removal of two large dams on the Elwha River, Washington State, the largest dam removal yet completed globally, created extensive cutbank exposures of reservoir sediments, allowing the first characterization of the facies architecture of sediments through direct observation in reservoirs worldwide and providing an unparalleled opportunity to assess the relationship between environmental influences, such as changes in sediment supply, and their expression in the stratigraphic record. Using a combination of facies description from observation of 49 measured sections and >100...

This short commentary piece explores the concept of shared stewardship in the Forest Service as it relates to recreation planning and management. It offers examples of different types of networks of partners.

As the sole habitat for terrestrial life, the Earth's critical zone (CZ) refers to the upper, porous layer of the continental crust that is interacting with the circulating meteoric waters. Conceptually, water is central to the intriguing co‐evolution of both the hydrologic behaviour and the structure of the CZ. On one hand, the path and rate of water circulating through the CZ are shaped by the CZ physical structure itself, such as the distribution of material porosity and permeability. On the other hand, and at longer time scales, the circulating water shapes the CZ structure through...

Fish passage out of reservoirs is a critical issue for downstream movement of juvenile salmonids and other migratory species. Reservoirs can delay downstream migrations by juvenile salmon for months or years. Here, we examine whether a novel management activity implementing annual short‐term draining of a reservoir to streambed improves timely downstream migration of juvenile salmonids. We analyse 12 years of fish capture data from a screw trap located downstream of Fall Creek Reservoir (Oregon, USA) to examine changes in timing of passage out of the reservoir and to compare fish species...

We measured whole-tree transpiration of mature Fagus sylvatica and Picea abies trees exposed to ambient and twice-ambient O3 regimes (1xO3 and 2xO3 free-air fumigation). After eight years, mean daily total transpiration did not vary with the O3 regime over the 31 days of our study, even though individual daily values increased with increasing daily O3 peaks in both species. Although the environmental parameters were similar at 1xO3 and 2xO3, the main factors affecting daily transpiration were vapour pressure deficit in 2xO3 spruce and O3 peaks in beech. For a mechanistic explanation, we...

Scotch broom (Cytisus scoparius (L.) Link) is an invasive, N-fixing shrub in recently harvested Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii) forests in the Pacific Northwest. The ability of Scotch broom to dominate a site and displace Douglas-fir in this region may be mediated by site quality and site resource supply. Individual seedlings of Scotch broom (n = 46) and Douglas-fir (n = 46) were planted in a controlled nursery 'Cities and the Environment (CATE). 14: Article 4. ​​​38 p.​​​'setting and monitored over two years to test the effects of irrigation and fertilizat...

Data describing aircraft position and attitude are essential to computing return positions from ranging data collected during airborne laser scanning (ALS) campaigns. However, these data are often excluded from the products delivered to the client and their recovery after the contract is complete can require negotiations with the data provider, may involve additional costs, or even be infeasible. This paper presents a rigorous, fully automated, novel method for recovering aircraft positions using only the point cloud. The study used ALS data from five acquisitions in the US Pacific...