Treesearch

The Goosenest Adaptive Management Area was established in 1994 on the Klamath National Forest with the intent of evaluating late-successional forest characteristics. A large-scale experiment was established in the late 1990s to evaluate a range of management strategies. Treatments include combinations of mechanical thinning and prescribed fire. Observations 6 and 14 years after establishment were analyzed to evaluate effects on large tree component of the stand as well as species distribution and coarse woody debris. Thinning treatments accelerated growth of retained trees and modified...

Many fire-adapted forests across the United States where fire has been excluded have in-filled with shade-tolerant species, reducing the characteristic spatial heterogeneity. We used 1929 stem maps of historical forest conditions in the Sierra Nevada to develop a thinning prescription designed to restore a pattern of tree clumps, individual trees, and gaps. This "high variability" (HighV) thinning treatment was evaluated in a replicated experimental design along with a more standard regular “leave” tree spacing "low variability" (LowV) thinning treatment, and an unthinned control, all with...

The Adaptive Silviculture for Climate Change (ASCC) project is a collaborative effort that has established a series of experimental silvicultural trials across a network of different forest ecosystem types throughout North America. Scientists, land managers, and a variety of partners have co-developed a series of experimental sites as part of this multiregion study to research long-term ecosystem responses to a range of climate change adaptation approaches (Swanston et al. 2016). Silvicultural treatments at each study site were developed by using a modified process from Swanston et al....

The hundreds of Indigenous tribes in the United States harbor diverse perspectives about the natural world, yet they share many views that are important for ecosystem restoration efforts. This paper features examples of how such views have guided ecosystem restoration through partnerships between tribal communities and the U.S. Forest Service in the western United States. Traditional perspectives have influenced restoration by deepening the understanding of reference conditions, expanding consideration of system dynamics, and guiding treatment based upon ethical principles and beliefs....

Several formulations of the antiaggregation pheromone verbenone (4,6,6-trimethylbicyclo [3.1.1]hept-3-en-2-one) are registered to protect pine trees and forest stands from mountain pine beetle, Dendroctonus ponderosaeHopkins (Coleoptera: Curculionidae), but failures in efficacy are not uncommon. In 2011–2013, a novel formulation of (−)-verbenone was developed (SPLAT® Verb, 10.0% (−)-verbenone by weight, EPA Reg. No. 80286−20, ISCA Technologies Inc., Riverside, CA, USA) for protecting individual lodgepole pine, Pinus contortaDougl. ex Loud., and small stands of P. contortafrom mortality...

The host selection behaviour of the walnut twig beetle, Pityophthorus juglandis , was assessed by monitoring the landing rates of the beetles with sticky sheet traps on the host and nonhost hardwood branches. Sticky sheet traps were deployed for 8 weeks from 6 June to 2 August. 2017 in the Putah Creek Riparian Reserve, Davis, CA. Branches from host northern California black walnut, Juglans hindsii, were paired with branches from six nonhost hardwood species. The landing rate of P. juglandis(412 beetles trapped/8 weeks; 389 on host branches, 23 on nonhost branches) was significantly greater...

This plant profile for Rhamnus crocea and Rhamnus ilicifolia provides information on species distribution; taxononic relationships; ecological and evolutionary considerations for restoration; growth form and distinguishing traits; habitat characteristics; projected future suitable habitat; growth, reproduction and dispersal; biological interactions; ecological genetics; seed characteristics, germination requirements and processing; and plant uses including agriculture, restoration, and traditional products, plus an extensive bibliography. It is part of Riverside-Corona Resource Conservation...

This plant profile for Ceanothus crassifolius provides information on species distribution; taxononic relationships; ecological and evolutionary considerations for restoration; growth form and distinguishing traits; habitat characteristics; projected future suitable habitat; growth, reproduction and dispersal; biological interactions; ecological genetics; seed characteristics, germination requirements and processing; and plant uses including agriculture, restoration, and traditional products, plus an extensive bibliography. It is part of Riverside-Corona Resource Conservation District's...

This plant profile for Ceanothus cuneatus provides information on species distribution; taxononic relationships; ecological and evolutionary considerations for restoration; growth form and distinguishing traits; habitat characteristics; projected future suitable habitat; growth, reproduction and dispersal; biological interactions; ecological genetics; seed characteristics, germination requirements and processing; and plant uses including agriculture, restoration, and traditional products, plus an extensive bibliography. It is part of Riverside-Corona Resource Conservation District's...

Although nitrogen deposition and tropospheric ozone have impacted California forests for decades, broad scale studies of these impacts on forest growth and mortality are lacking. Because of the summer-dry climate over most of the state, forest responses to air pollution are expected to differ from more mesic climates. In this study, data from US Forest Service Forest Inventory and Analysis (FIA) permanent (remeasured) plots were combined with modelled atmospheric N and S deposition and an ozone exposure index to evaluate tree growth and mortality responses in California. Seven of 18...