The Williston Basin, located in the NorthernGreat Plains, is experiencing rapid energy developmentwith North Dakota and Montana being the epicenter ofcurrent and projected development in the USA. Theaverage single-bore well pad is 5 acres with an estimated58,485 wells in North Dakota alone. This landscapeleveldisturbance may provide a pathway for the establishmentof non-native plants. To evaluate potentialinfluences of energy development on the presence andabundance of non-native species, vegetation surveyswere conducted at 30 oil well sites (14 ten-year-oldand 16 five-year-old wells) and 14 control sites in nativeprairie environments across the Williston Basin. Nonnativespecies richness and cover were recorded in fourquadrats, located at equal distances, along four transectsfor a total of 16 quadrats per site. Non-natives wererecorded at all 44 sites and ranged from 5 to 13 species,7 to 15 species, and 2 to 8 species at the 10-year, 5-year,and control sites, respectively. Respective non-nativecover ranged from 1 to 69, 16 to 76, and 2 to 82 %.Total, forb, and graminoid non-native species richnessand non-native forb cover were significantly greater atoil well sites compared to control sites. At oil well sites,non-native species richness and forb cover were significantlygreater adjacent to the well pads and decreasedwith distance to values similar to control sites. Finally,non-native species whose presence and/or abundancewere significantly greater at oil well sites relative tocontrol sites were identified to aid management efforts.
