Tanner has been a constant advocate for urban forests since 2011. He has been a land steward for a nature preserve; urban forester for 8 years leading a community tree planting program; and a clean water & public lands advocate. Most recently, he built and led an international urban forestry program as Director of Urban Forestry at One Tree Planted, supporting many initiatives including the launch of the Tree Equity Alliance with American Forests. His work has received multiple awards, including the inaugural Headwaters Award from Arbor Day Foundation, Chesapeake Forest Champion award from the Alliance for the Chesapeake Bay, and Gold Leaf award from the International Society of Arboriculture. He is an ISA-certified Arborist; holds certificates in the Fundamentals of Leadership, Organizational Analysis, and Large Account Management; and is a founding member and former Chair of his municipal Tree Board.