James (Jim) O'Callahan used to teach the 37-Forms Cheng Man-ch'ing / Yang Style T'ai Chi Ch'uan (Taijiquan) solo Short Form Set in Woodland, some time during the 1980's and 1990's. It would be interesting to know where he taught, and more exactly what dates (perhaps some of his Woodland students could fill in here). Jim Sifu learned the 37-Forms Set either from Master Benjamin Pang Jeng Lo of San Francisco, or from Sifu Martin Inn, one of Master Lo's senior students also of San Francisco, or possibly from both of them (someone else might want to correct this, and it would be interesting to know when he studied with either of them).
Occasionally Jim Sifu would invite Sifu Robert Amacker from Marin, who had studied with Master Cheng, as well as Master Lo to come to Woodland to teach weekend workshops (it would be interesting to know further details about these workshops, such as when and where taught, who attended, what taught).
Since February 2009, The City of Trees T'ai Chi Ch'uan & Ch'i Kung - Kung Fu, Beginners' Grove, also a Yang Style Tai Chi group, has met semi-privately, on an ongoing basis, first on Tuesday evenings, and then on Monday evenings, 6:30pm - 8:00pm, at First Street and Main Street in downtown Woodland. These class / practice sessions are lead by YCSifu.