This fungus was isolated from the surface-disinfected (80% ethanol) inner bark of one tree in an old-growth cedar forest in northern Montana. Taxomyces andreanae was cultured bytransferring hyphal tips from water agar, on which bark pieces had been cultured, onto a modified-mycological agar( S-7 medium consists of 1 g of glucose, 3 g of fructose, 6 g of sucrose, 1 g of Na⁺-acetate, 1 g of soytone, 1 mg of thiamine, 1 mg of biotin, 1 mg of pyridoxal, 1 mg of Ca²⁺-pantothenate, 3.6 of mg MgSO₄, 6.5 mg of CaNO₃, 1 mg of Cu(N03)2, 2.5 mg of ZnSO₄, 5 mg of MnCI₂, 2 mg of FeCI₃, 5 mg of phenylalanine, 100 mg of Na⁺-benzoate, and 1 ml of 1 M KH₂PO₄ buffer (pH 6.8) per liter. Sugar ratio is identical to that occurring in the inner bark of Pacific yew. Modified mycological agar consists of 10 g of bacto-soytone, 40 g of glucose, 15 g of bacto-agar, 1 g of Na⁺-acetate, and 50 mg of sodium benzoate per liter. ). The mycelium was then successively transferred to eliminate traces of taxol or other taxanes carried over from the original tree source.Transfers of small agar plugs to broth cultures were made from mycelia that hadgrown 3 to 7 days. After this period, mycelia appeared to go into a quiescent state.Taxomyces andreanae was stored in water at 4 ℃ and grown on a semi-defined culture medium. The conidia of T. andreanae do not germinate, therefore we transferred pieces (0.5 by 0.5 cm) of agar block containing the mycelial mats to sterilized S-7 medium. Optimum conditions were as a still culture, at 25 ℃ , with a surface-to-volume ratio of 1.3 (cm²:ml). After 21 days of incubation, the culture was filtered through cheesecloth. Chlorocholine chloride (at 1 mg/ml) in the medium abolished taxol production.