PecanProject/pecan — pull request #199 by dlebauer (2014-08-25 18:02:24+00:00)
Title: resolves broken builds (gh-198); but this is a patch. 

There is an underlying issue with query.covariates that causes it to return an empty dataframe (line 430 of query.trait.data.R); there is also a hack to put canopy layer covariates in a separate dataframe because otherwise filter.sunleaf.traits does not work