Hoyt Arboretum web site says "There are two miles of trails suitable for wheelchairs, baby strollers, and visitors who appreciate firm footing."

The Tours and Walks page lists a 1-Mile Walk Suitable for Strollers or Wheelchairs. This walk, the Overlook Trail, is on an (almost) continual moderate downhill grade from the Visitor Center. There are a few roots bulging up through the asphalt but it's in reasonably good shape. At the bottom of the walk you can cross the street and enter the paved, spiral, gently upward-sloping path of the Oregon Vietnam Veterans' Memorial.

The arboretum grounds are open and free to the public from 6:00 am to 10:00 pm daily.