guardian spirits called taung saung nats () appears to act as a deterrent against environmental destruction up to a point. Indiscriminate felling particularly of large trees is generally eschewed owing to the belief that they are dwellings of tree spirits called yokkazo (; tree spirit) and that such an act would bring the wrath of the nat upon the perpetrator. Popular nat festivals The most important nat pilgrimage site in Burma is Mount Popa, an extinct volcano with numerous temples and relic sites atop a mountain 1300 metres tall located near Bagan in central Burma. The annual festival is held on the full moon of the month of Natdaw (December) of the Burmese calendar. Taungbyone, north of Mandalay in Madaya Township, is another major site with the festival held each year starting on the eleventh waxing day and including the full moon in the month Wagaung (August). Yadanagu at Amarapura, held a week later in honour of Popa Medaw ("Mother of Popa"), who was the mother of the Taungbyone Min Nyinaung ("Brother Lords"), is also a popular nat festival. Nats are ascribed human characteristics, wants, and needs; they are flawed, having desires considered derogatory and immoral in mainstream Buddhism. During a nat pwè, which is a festival during which nats are propitiated, nat kadaws ( "wife of the spirit", i.e. "medium, shaman") dance and embody the nats. Historically, the nat kadaw profession was hereditary and passed from mother to daughter. Until the 1980s, few nat gadaws were male. Since the 1980s, persons identified by outsiders as trans women have increasingly performed these roles. Music, often accompanied by a hsaing waing ("orchestra"), adds much to the mood of the nat pwè, and many are entranced. People come from far to take part in the festivities in various shrines called nat kun or nat naan, get drunk on palm wine and dance wildly in fits of ecstasy to the wild beat of the Hsaing waing music, possessed by the nats. Whereas nat pwès are annual events celebrating a particular member of the 37 Great Nats regarded as the tutelary spirit in a local region within a local community, with familial custodians of the place and tradition and with royal sponsorship in ancient times, hence evocative of royal rituals, there are also nat kannah pwès where individuals would have a pavilion set up in a neighbourhood and the ritual is generally linked to