Sandpoint forester pushes tighter prohibited tree list, recommends limits on maples and ash

Sandpoint’s city forester told the Urban Forestry Commission on July 24 that the Arboriculture Manual should emphasize a clear list of prohibited street trees rather than attempt an exhaustive approved-species catalog. Eric Bush said a long approved list would inevitably miss species people might plant and would discourage suitable, locally available specimens. “It’s much more important that we have a tight prohibited street tree list than a tight approved street tree list,” Bush said during the meeting. Bush reviewed species currently in the city’s prohibited list as written in existing code and the urban forestry management plan: boxelder, cottonwood, poplar, willow, mountain ash (initially listed), American elm, fruit and nut trees, Ailanthus (tree-of-heaven) and bigleaf maple. He told commissioners he would remove mountain ash from the prohibition and treat it on a case-by-case basis. He also said the management plan recommends a temporary prohibition on planting additional maples (Acer) because maples make up roughly 20–25% of Sandpoint’s canopy and that heavy reliance on one genus increases the risk of catastrophic canopy loss if a pest or disease arrives. Bush described a possible approach for a temporary ban on new Acer plantings, with exceptions for dwarf or ornamental varieties such as some Japanese maples, and suggested the commission consider a short “encouraged” list of species (for example, transmission-line-friendly trees) rather than a long approved list. The commission discussed referencing established technical materials rather than reprinting them in full; Bush said he plans to include digestible planting and maintenance guidance and to reference the U.S. Forest Service and ISA (International Society of Arboriculture) best-practice materials where copyright and legal review permit. He said any revised manual will go through legal review before adoption. No formal vote on the manual was taken; the item will return as the draft is refined.