Effects on Plants

Disturbances, management, and changing environmental conditions have reshaped the sagebrush biome within the western United States. As a result, sagebrush cover and configuration have varied over space and time, influencing ecological processes and species' use of the landscape. Characterizing changes in sagebrush ecosystem connectivity over time will help us understand the effects of those...

We are studying how herbicides sprayed onto soil to prevent the establishment of exotic annual grasses such as cheatgrass may impact the health, growth resources and microbiota of soils in sagebrush-steppe, where herbicide use is an important and common tool. Our findings will help make herbicide applications more successful.

Pre-emergent herbicides applied to soil are a primary tool for reducing exotic annual grasses, such as cheatgrass, in sagebrush steppe rangelands. Effective herbicide application can allow existing perennials to grow and spread to outcompete cheatgrass, preventing reinvasion, but most perennials are slow-growing and require more years of relief from annual-grass competition than standard...

In order to break the annual grass fire-cycle in the sagebrush steppe, land managers use pre-emergent herbicides to reduce annual grass populations and seeding to increase fire-tolerant perennials. These tools must be applied to the same soils in ways that are not counterproductive, and their application must therefore be staggered in time, which we refer to as layering. Livestock grazing can also...

Management partners have identified a major need to understand the short and long-term consequences of altered wildfire patterns, vegetation change, climate, and management actions for the carbon cycle. This project aims to quantify carbon storage and greenhouse gas emissions in sagebrush rangelands. Researchers will link findings to the Sagebrush Conservation Design Framework and provide...

WERC scientists are defining the past, present, and future of wildfires for wildlife and human communities. Explore this webpage to learn about specific, ongoing projects across California and parts of Nevada.

Land managers have invested considerable funding to decrease fuel loads and restore resilient ecosystems in forests and rangelands, using techniques such as grazing, mowing, herbicides, and thinning. Yet, little information is available about how such restoration activities have influenced wildlife species and habitats. We are conducting empirical studies and developing novel approaches to better...

This research theme examines the impacts of prescribed fire on plant productivity, soil physical, chemical, and biological characteristics, and nutrient leaching. Results from this research will enable improved decision-making of how to manage fire-prone forests to maintain long-term forest fertility and productivity, especially across wide climate gradients characteristic of the Pacific Northwest...

How will increased drought affect forest fire severity? WERC’s Dr. Phil van Mantgem is testing the idea increased drought stress may affect forest fire severity independent of fire intensity. Drought stress prior to fire can affect tree health, potentially resulting in a higher sensitivity to fire-induced damage. Thus, with drought there may be ongoing increases in fire severity (the number of...

Fuel conditions and fire regimes in western forests and deserts have been altered due to past land management, biological invasions, and recent extreme weather events and climate shifts. These changes have created extreme fire risk to local and regional communities, threatening their economic health related to wildland recreation, forest production, livestock operations, and other uses of public...