This data package contains soil N data collected in May 1986 to survey N availability in a variety of grass and mesquite habitats at the Jornada Experimental Range (JER) during the early years of the Jornada LTER (I-II). The purpose of this study was to measure inorganic soil nitrogen in the context of shifting grasslands to mesquite dominated ecosystems. Sites include fluff grass (Dasyochloa pulchella), black grama (Bouteloua eriopoda), Sporobolus/Gutierrezia, playa mesquite, and arroyo mesquite (Prosopis glandulosa). Soil samples collected on March 12-13, 1986 within the clumps of grass or beneath mesquite at each site, generally 20 cm deep or to the hard pan (whichever came first). Inorganic nitrogen leaching was measured for 28 weeks for each sample. This study is complete.