Native-exotic richness relationship in Michigan prairies

A better understanding of factors underlying positive correlations between native and exotic species richness, a pattern that is nearly ubiquitous at large scales in plant communities, may help managers modify these correlations to favor native plant species during restoration. Across 29 tallgrass prairie sites restored through seed sowing onto former agricultural lands, we examined whether the relationship between native and exotic richness is: 1) altered by management, such as seed additions and prescribed fire, 2) controlled instead by environmental conditions and successional processes, or 3) altered by management in certain environments and not in others.
Two datasets. Both contain exotic and native plant SR across several prairie restorations, as well as data on seed mix properties (mix richness, seeding rate), fire frequency, age of restoration. \"BassettNativeExoticData\" contains data on additional factors that influence invasion: environmental factors (PCA of surrounding land us..., See related dataset Grman et al. 2014. Ecology, 95(8), 2014, p. 2363 for more info., , # Native-exotic richness relationship in Michigan prairies

[https://doi.org/10.5061/dryad.8gtht76w9](https://doi.org/10.5061/dryad.8gtht76w9)

Two datasets. Both raw and standardized ([value-mean]/sd) values for most data. 

Both contain exotic and native plant SR (exoticSR.2011, nativeSR.2011) across several prairie restorations, and the residuals from regressing exotic on native SR (resid.site.enrr). This value is a response variable, used to test hypotheses about variation around the correlation of exotic and native SR. 2) And properties of seed mixes used in the restoration: number of species sown (mix.SR, mix.SR.std) and g seeds/m2 sown (g.seeds.m2, dens.std); number of prescribed fires per decade (fire.return, fire.std), and age of restoration in 2011 (age.2011, age.std).

\"BassettNativeExoticData.csv\" contains data on additional factors that influence invasion. *Sources of propagules:* PCA of surrounding land use derived from analyzing proportions of cover types within 500m (la...,