Various resins, such as amber, myrrh, frankincense, and halmaddi (the resin of a tree) are used in traditional masala incense, usually as a fragrant binding ingredient, and these will add their distinctive fragrance to the finished incense. Some resins, such as gum Arabic, may be used where it is desirable for the binding agent to have no fragrance of its own. Halmaddi has a particular interest to Western consumers, possibly through its association with the popular Satya Nag Champa. It is an earth coloured liquid resin drawn from the Ailanthus triphysa tree; as with other resins, it is a viscous semi-liquid when fresh, it hardens to a brittle solid as it evaporates and ages. Some incense makers mix it with honey in order to keep it pliable. Due to crude extraction methods which resulted in trees dying, by the 1990s the Forest Department in India had banned resin extraction; this forced up the price of halmaddi, so its usage in incense making declined. In 2011, extraction was allowed under leasing agreements, which increased in 2013, though production is still sufficiently limited for the resin to sometimes be stolen via improper extraction to be sold on the black market.