Peppermint Quality Reduction Noted

The Herb Profile in the  Herbalgram #72 points out that increased demand for peppermint has resulted in double harvesting in the United States, which produces over 90% of the world supply of over 4000 tons per year.

They cite an Australian publication for related information about the production and stresses on it from disease and climate issues. Presumably it would behoove those who demand the highest quality of peppermint oil to require suppliers to specify which harvest the oil is from.