Treesearch

Plant control methods have been developed to reduce weed species that are often problematic in agricultural systems. However, these methods can create new challenges, such as herbicide resistance. Determining which plant traits are associated with herbicide resistance can assist managers in identifying species with the potential to develop herbicide resistance and to better understand factors contributing to the evolution of herbicide resistance. We used random forest models to model herbicide resistance of noxious weeds as a function of 10 biological and ecological plant characteristics....

Invasive species cause billions of dollars of economic losses and other damage every year in the United States. Environmental DNA (eDNA) sampling can help managers determine whether a problem species is present in an area, even when its numbers are low or it is hard to observe. This capability makes it a powerful tool for early detection and monitoring. The National Invasive Species Council (NISC), recognizing eDNA sampling as a promising tool for invasive species surveillance and management, began in 2020 to look for ways to make this tool more tangible for managers. Rocky Mountain...

Climate forecasts and disturbance mapping increasingly inform strategies for ecological restoration practices. Our study objectives were to understand how a postfire rehabilitation seed mix responds to fire, seeding timing, and changes in fall precipitation timing due to climate change. We planted seeds commonly used in the Great Basin Desert of North America on soil cores in a randomized block design. We imposed two experimental treatments, experimental fire (burned seedbeds or unburned seedbeds) and timing of seeding with simulated precipitation (early September vs. mid-October) in a...

The USDA Water Erosion Prediction Project (WEPP) is a process-based soil erosion prediction model. WEPP uses three soil erodibility parameters: rill erodibility (Kr), interrill erodibility (Ki), and critical hydraulic shear stress (τc). In this study, a new parameterization approach for estimating erodibility was developed for WEPP applications on rangelands. Data from overland flow experiments on disturbed and undisturbed rangelands were used to develop empirical equations to predict rill erodibility variation as a function of vegetation cover and soil texture. Data from rainfall simulatio...

The synergy between human land use and climate change is accelerating the global decline of biodiversity. In the fragile Himalayas, this trend has a strong ecological impact on wildlife communities, and a better understanding is needed to discern changes in the mechanisms. This study aims to understand the effects of land use and climate change on the functional (FD) and phylogenetic diversity (PD) of mammal and bird communities across the land use gradient.

This study uses remote sensing and GIS techniques to examine the intensity and dynamics of land use/cover change and environmental indices across a four-decade period in the Chingola district of Zambia, from 1972 to 2020 using five classification stages (1972, 1992, 2001, 2013, and 2020). A total of 10 key climate change detection monitoring indices were generated using RClimDex to examine the implications of land degradation on the bioclimatic factors from 1983 to 2020. The findings revealed a significant expansion in Built-ups (7.3%/year), farmlands (3.18%/year), and mining areas...

Forest management goals and objectives have vastly expanded in recent decades. Many managers and silviculturists are challenged to produce more than just timber from our nation’s forests. Future forests are expected to deliver complex and often integrated management objectives such as providing a unique sense of place and naturalness, 2022 National Silviculture Workshop Foundational Concepts in Silviculture: Emphasis on Reforestation and Early Stand Improvement wildlife habitat and forage, and resilience to disturbance and global change - all in addition to renewable forest products.

Traditionally, the primary focus of cleaning has been to equally space residual trees to maintain full stocking (e.g., 12 x 12 ft or 14 x 14 ft) by removing competition. Preferred species are western white pine, western larch, and ponderosa pine; however, when these species are not sufficiently abundant, shade tolerant species are left to maintain full stocking.

Throughout the range of ponderosa pine (Pinus ponderosa), clearcut harvesting and planting through the late 20th century resulted in widespread even-aged forests, which excelled at regenerating shade-intolerant species and producing wood in an operationally simple way. Two decades into the 21st century, timber production objectives are now also balanced with a variety of nontimber objectives such as increasing resistance and resilience to disturbances and managing wildlife habitat.

Reforestation on the Rogue River-Siskiyou National Forest on the Powers and Gold Beach Ranger Districts is driven by the need to accelerate the development of late successional habitat in stands less than 80 years old. Prior regeneration harvest emphasized clear-cutting with regeneration of Douglas-fir. Douglas-fir is not a shade tolerant species and will not regenerate naturally under canopy cover. Therefore, to develop a multilayered canopy, reforestation of shade-tolerant species like western hemlock, grand fir, and Port-Orford-cedar is needed. Multilayered canopies provide habitat for...