Levels of pH (reaction) classes including descriptive name, and range from low to high pH
data(reactionclass)
An object of class data.frame
with 11 rows and 3 columns.
Soil Science Division Staff. (2017) Soil Survey Manual. C. Ditzler, K. Scheffe, and H.C. Monger (eds.). USDA Handbook 18. Government Printing Office, Washington, D.C.