What kind of stats test would you use? Help!?

I'm writing I research report and one of the questions I need to address is...Can the distribution of any of the 3 species across the plot be explained in relation to the physical environment? If so, in what way? I have data on the stem density of three different species and the pH, gradient, elevation, and wetness index for each plot in the study area. I was going to run a multiway ANOVA but I can't get my data to work right in R. Should I be using a different test, maybe a Chi-squared?