Of the twenty-two components of tea decoctions commonly used to treat infections, only Scutellaria, Taraxacum, Tussilago and Glycyrrhiza exhibited antimicrobial activity. The activity, when present, was organism specific, i.e., anti-Staphylococcus aureus, including anti-MRSA activity under aerobic and/or anaerobic conditions. However, with the exception of Scutellaria, sub-inhibitory concentrations of the herbs exhibited a pattern of inducing enhanced production of biofilm.