Precipitation and invasive winter annual grass data for the Great Plains

Aim: Climate change is predicted to increase spatial extent and equilibrium abundance of many invasive species, and there is evidence this may already be happening.  In North American grasslands, the most concerning invaders are winter annuals.  Understanding winter annual responses to climate change is challenging because these species are regulated by weather during multiple seasons, unlike perennials that are overwhelmingly regulated by growing season precipitation.  We quantified downy brome (Bromus tectorum L. (ITIS)) and Japanese brome (Bromus japonicus Thunb.) responses to precipitation and temperature.  These functionally similar invasive winter annual grasses are destroying wildlife habitat, reducing livestock production, and increasing wildfire risks across vast portions of the western U.S. 
Location: Great Plains, U.S.A.
Methods: Using Bayesian methods to integrate experimental and long-term (30 yr) monitoring data, we estimated the effects of precipitation and temperature on..., We studied ten sites separated by ≤13 km on the 22,250-ha Fort Keogh Livestock and Range Research Laboratory (46°22’53”N 105°53’03”W).  Soils were deep, well-drained loams (Pinehill, Eapa, Sonnett, Yamacall, Glendive) or silty loams (Kobase).  In addition to bromes, vegetation included native perennial cool-season grasses (e.g. Pascopyrum smithii (Rydb.) A. Love and Hesperostipa comata [Trin. & Rupr.] Barkworth), native perennial warm season grasses (e.g Bouteloua gracilis (Willd. ex Kunth) Lag. ex Griffiths), native and nonnative forbs (e.g. Achillea millefolium L.), cactus (Opuntia polyacantha Haw.), and shrubs (e.g. Artemisia tridentata Nutt. and Artemisia cana Pursh).
One site was used for long-term fire research (Vermeire and Russell 2018, Vermeire et al. 2020), and from this site we used data from nine non-burned control plots (15 × 20 m) (Appendix A1: Table S1).  This site was not grazed since 2001.  Near peak standing crop from 2008 to 2020, four randomly placed 2500-cm2 cir..., , # Precipitation and invasive winter annual grass data for the Great Plains

[https://doi.org/10.5061/dryad.jh9w0vthk](https://doi.org/10.5061/dryad.jh9w0vthk)

## Description of the data and file structure

### Files and variables

Data fields, which are named in the first row of the file, indicate:

1\) Site. This is a number identifying the research site.  To determine which number corresponds with which site, see Appendix A1.
2\) Year of vegetation sampling
3\) Julian day of vegetation sampling
4\) Precipitation in millimeters from September 1 to November 15 three years before vegetation measurement 
5\) Precipitation in millimeters from September 1 to November 15 two years before vegetation measurement
6\) Precipitation in millimeters from September 1 to November 15 the year before vegetation measurement
7\) Precipitation in millimeters from March 1 to June 15 the year before vegetation measurement
8\) Precipitation in millimeters from March 1 to June 15 the year of vegetation measu...