Invasive Annual Grass (IAG) Spatial Dataset Compilation and Synthesis

Across the West, invasive annual grasses are a major threat to sagebrush rangelands, impacting plant communities, wildlife habitat, and wildfire risk. Numerous spatial datasets mapping invasive annual grasses exist; however, land managers often struggle to identify which of these datasets are most relevant to their work or are unaware that these data exist at all. Through a suite of products, experts collated invasive annual grass spatial datasets and identified the similarities and differences among them. Further, they provide guidance to potential users on selecting appropriate spatial data for their needs. 

The USGS collected and summarized 23 spatial datasets:

Frequently Asked Questions

Q: Why should I use this summarization of maps and spatial datasets?

A: It’s a curated summary of information to help save you time in finding relevant resources. It’s meant to provide a systematic way to compare different mapping options for invasive annual grasses.

Q: Where do I download this data?

A: Links to GIS spatial data can be found in the compendium and database, as well as on the Sagebrush Ecosystem Data Viewer and SageDAT.

Q: Why only these three IAG species?

A: These three invasive grass species (cheatgrass, medusahead, ventenata) represented the greatest interest/concern among agency stakeholders working in the sagebrush biome, the focal area for this project. However, there are other invasive grasses of concern.

Q: How do I use this suite of products to find maps and spatial datasets?

A: See use cases below

• I'm trying to find local data and want to quickly check if a dataset could be useful to me: Check out this easy-to-use web viewer that you don’t need GIS software to explore the datasets.
• I want to read short synopses to know what’s out there: Head to the compendium.
• I want to know what criteria to consider when selecting spatial datasets for a project: Dive into the user guide.
• I want to understand the similarities and differences among these spatial datasets (e.g., to compare and filter the datasets represented): Explore the downloadable database of invasive annual grass spatial products.
• I want to read about recent IAG mapping and ideas for co-producing new spatial data products: Read the journal article.

Q: Why isn’t my favorite dataset included?

A: This project focused on publicly available spatial datasets that were peer-reviewed, published from January 2010 through February 2021, and covered regional (or larger) spatial extents. The spatial datasets summarized were created using spatial-statistical models resulting in  invasive annual grass predictions across large landscapes. Many available datasets did not meet these inclusion criteria. Small and localized datasets are not included at this time. Some non-map datasets, including point location and occurrence databases, were noted in the Compendium Appendix but not summarized in these products.

Q: There are a few dozen maps in this catalogue. Do we really need more spatial data products?

A: In many cases, yes. They are all constructed differently and lead to different strengths and weaknesses of application. More can be done to increase or improve spatial mapping of invasive annual grasses, particularly for lesser-mapped species such as ventenata and medusahead.