Sesquiterpene synthase that catalyzes the formation of a blend of sesquiterpenes and sesquiterpenoid alcohols (PubMed:27421723). Converts farnesyl diphosphate to tau-cadinol (PubMed:27421723). (2E,6E)-farnesyl diphosphate + H2O = diphosphate + tau-cadinol kcat is 0.00136 sec(-1) with (2E,6E)-farnesyl diphosphate as substrate. Optimum pH is 8. Secondary metabolite biosynthesis; terpenoid biosynthesis. Monomer. Constitutively expressed in aerial tissues, but barely observed in roots. Induced by fungus spore (F. graminearum) inoculation and methyl jasmonate (MeJA) treatment in leaves (PubMed:27421723). Triggered by abscisic acid (ABA) in roots (PubMed:27421723). The Asp-Asp-Xaa-Xaa-Asp/Glu (DDXXD/E) motif is important for the catalytic activity, presumably through binding to Mg(2+). Belongs to the terpene synthase family.