Supporting Information Table 1S. Examples of observational and experimental evidence that harsh sites are less invaded or resistant to invasion Environment Stressor(s) Observational evidence that harsh sites are Experimental evidence of abiotic or less invaded biotic resistance to invasion in harsh sites Nitrogen-poor Low nitrogen (and Brooks 2003; Kolb 2002; McDougall Chase and Knight 2006; Holdredge et al. et et al. sites sometimes 2005; McLendon and Redente 1991 2010; James 2011 (review); al. et al. phosphorus) Morgan 1994; Pashke 2000; Prober et al. 2005; Rickey and Anderson 2004; et al. Steers 2011; Török 2014; et al. et al. Xie 2010 et al. Low phosphorus Boughton 2011; Dimitrakopoulos 2005; Cherwin 2009; Huenneke et al. et al. et al. sites Dorrough 2006; Fisher 2006; Gu 1990; Leishman et al. 2004, Leishman et al. et al. 2006; Lake and Leishman 2004; Morgan and Thomson 2005; Van 1999 et al. 1998; Xiao-Yun 2006 et al. Saline, sodic, High salinity, sodium Baker 1986; Uyeda 2013 He 2012; Kuhn and Zedler 1997; et al. et al. and alkaline content, and/or Konisky and Burdick 2004; Mesléard et soils alkalinity 1993; Silliman and Bertness 2004; al. Uyeda 2013; Veblen and Young et al. 2009; Zedler 1990 et al. Serpentine sites Low Ca:Mg, low Baker 1986; Gram 2004; Huenneke Going 2009; Huenneke et al. et et al. et al. nutrients, high 1990; Harrison 1999a/b, 1999b; Jaffre 1990; and Claassen 2006; Turitzin al. O’Dell alkalinity, shallow/dry 1992; Kruckeberg 1954, 1984; McNaughton 1981; Weiss 1999, 2006 soil, heavy metals 1968; Mooney 1986; Walker 1954; et al. Xeric sites Water limitation Daehler 2001; Goergen and Brooks 2009; Baruch and Fernandez 1993; Goergen Harrington 1991; Lonsdale 1999; Larson and Daehler 2001, 2002; Hamilton et et al.
Supporting Information Table 1S. Examples of observational and experimental evidence that harsh sites are less invaded or resistant to invasion Environment Stressor(s) Observational evidence that harsh sites are less invaded Experimental evidence of abiotic or biotic resistance to invasion in harsh sites Nitrogen-poor sites Low nitrogen (and sometimes phosphorus) Brooks 2003; Kolb et al. 2002; McDougall et al. 2005; McLendon and Redente 1991 Chase and Knight 2006; Holdredge et al. 2010; James et al. 2011 (review); Morgan 1994; Pashke et al. 2000; Prober et al. 2005; Rickey and Anderson 2004; Steers et al. 2011; Török et al. 2014; Xie et al. 2010 sites Low phosphorus Boughton et al. 2011; Dimitrakopoulos 2005; Dorrough et al. 2006; Fisher et al. 2006; Gu 2006; Lake and Leishman 2004; Morgan 1998; Xiao-Yun et al. 2006 Cherwin et al. 2009; Huenneke et al. 1990; Leishman et al. 2004, Leishman and Thomson 2005; Van et al. 1999 Saline, sodic, and alkaline soils High salinity, sodium content, and/or alkalinity Baker 1986; Uyeda et al. 2013 He et al. 2012; Kuhn and Zedler 1997; Konisky and Burdick 2004; Mesléard et al. 1993; Silliman and Bertness 2004; Uyeda et al. 2013; Veblen and Young 2009; Zedler et al. 1990 Serpentine sites Low Ca:Mg, low nutrients, high alkalinity, shallow/dry soil, heavy metals Baker 1986; Gram et al. 2004; Huenneke et al. 1990; Harrison 1999a/b, 1999b; Jaffre 1992; Kruckeberg 1954, 1984; McNaughton 1968; Mooney et al. 1986; Walker 1954; Going et al. 2009; Huenneke et al. 1990; O’Dell and Claassen 2006; Turitzin 1981; Weiss 1999, 2006 Xeric sites Water limitation Daehler 2001; Goergen and Brooks 2009; Harrington 1991; Lonsdale 1999; Larson et Baruch and Fernandez 1993; Goergen and Daehler 2001, 2002; Hamilton et al.