Creates a ggplot2 plot of all sites that meet the user-specified site code (i.e., three letter abbreviation) and/or habitat criteria. See lter_sites for the full set of site information including accepted site codes and habitat designations (unrecognized entries will trigger a warning and be ignored). Lines are grouped and colored by habitat to better emphasize possible similarities among sites
Arguments
- sites
- (character) three letter site code(s) identifying site(s) of interest 
- habitats
- (character) habitat(s) of interest. See - unique(lter_sites$habitat)
- colors
- (character) colors to assign to the timelines expressed as a hexadecimal (e.g, #00FF00). Note there must be as many colors as habitats included in the graph 
Examples
# Make the full timeline of all sites with default colors by supplying no arguments
site_timeline()
 # Or make a timeline of only sites that meet certain criteria
site_timeline(habitats = c("grassland", "forest"))
# Or make a timeline of only sites that meet certain criteria
site_timeline(habitats = c("grassland", "forest"))
