Taxonomic reference lists are not included in vegdata to keep the package small. 
For taxonomic harmonization a Turboveg list with additional column ParentID must be available in the search path.

Reference lists "GermanSL" and "EuroSL" can be downloaded 
from https://germansl.infinitenature.org/
an https://eurosl.infinitenature.org/ respectively
into your tv_home directory, if needed.
