Weekly Changes of Exotic Annual Grasses (EAG) abundance in the Sagebrush Biome, USA, 2024

These datasets provide weekly differences of early estimates of 2024 fractional cover for exotic annual grass (EAG) that were released from April to late June. The EAG estimates were publicly released within 7-13 days of the latest satellite observation used for that version. Each weekly release contained five fractional cover maps along with their corresponding confidence maps for: 1) a group of 16 species of EAGs, 2) cheatgrass (Bromus tectorum); 3) Field Brome (Bromus arvensis); 4) medusahead (Taeniatherum caput-medusae); and 5) Sandberg bluegrass (Poa secunda). The datasets presented here are difference maps for the collective group of 16 EAG species. The difference maps were developed by subtracting the previous early estimate of EAG from the current week (for example Week 2 minus Week 1). This release contains nine difference maps from the 10 weekly early estimates of EAG. These weekly difference maps depict the amount and location of EAG abundance change each week.  The geographic coverage includes much of the sagebrush biome classified as shrubs or grassland/herbaceous by the 2021 National Land Cover Database at or below 2350-m elevation. 
Note:
Exotic Annual Grass Week 2 - Week 1 Difference Map was developed by subtracting cover maps created using imagery from no later than April 12 from maps created using imagery no later than April 21.
Exotic Annual Grass Week 3 - Week 2 Difference Map was developed by subtracting cover maps created using imagery from no later than April 19 from maps created using imagery no later than April 26.
Exotic Annual Grass Week 4 - Week 3 Difference Map was developed by subtracting cover maps created using imagery from no later than April 26 from maps created using imagery no later than May 3.
Exotic Annual Grass Week 5 - Week 4 Difference Map was developed by subtracting cover maps created using imagery from no later than May 3 from maps created using imagery no later than May 10.
Exotic Annual Grass Week 6 - Week 5 Difference Map was developed by subtracting cover maps created using imagery from no later than May 10 from maps created using imagery no later than May 18.
Exotic Annual Grass Week 7 - Week 6 Difference Map was developed by subtracting cover maps created using imagery from no later than May 18 from maps created using imagery no later than May 24.
Exotic Annual Grass Week 8 - Week 7 Difference Map was developed by subtracting cover maps created using imagery from no later than May 24 from maps created using imagery no later than June 1.
Exotic Annual Grass Week 9 - Week 8 Difference Map was developed by subtracting cover maps created using imagery from no later than June 1 from maps created using imagery no later than June 10.
Exotic Annual Grass Week 10 - Week 9 Difference Map was developed by subtracting cover maps created using imagery from no later than June 8 from maps created using imagery no later than June 16.

Tags: annual-grass, annual-herbaceous, arizona, california, cheatgrass, colorado, exotic, field-brome, great-basin, harmonized-landsat-sentinel, idaho, invasive-species, kansas, medusahead, montana, ndvi, nebraska, nevada, new-mexico, nonindigenous-species, north-dakota, noxious, oklahoma, oregon, perennial-grass, poa-secunda, red-brome, remote-sensing, rye-brome, sagebrush, soft-brome, south-dakota, texas, texas-brome, united-states, usgs-672b9af8d34e16b32e7391a0, utah, washington, weekly-changes, western-united-states, wyoming
Organization: Department of the Interior