Approved Street Trees

Select the tabs below to find the approved trees for street use, along with their pruning, spacing, and shade calculation details. In addition, check the Prohibited Trees tab to find out which trees cannot be used as street trees. For other street tree information, go to the following links:
  1. Small Trees
  2. Medium Trees
  3. Large Trees
  4. Prohibited Trees
20 Foot Crown Diameter Canopy Trees
  • Chanticleer Pear (Pyrus calleryana 'Glen's Form')
  • Crape Myrtle (Lagerstroemia indica)
  • Crimson Spire Oak (Quercus x 'Crimschmidt')
  • Easter Redbud (Cercis Canadensis)
  • Flowering Plum (Prunus cerasifera)
  • Lavalle Hawthorn (Crataegus x lavallei)
  • Musahsino Zelkova (Zelkova serrate 'Musashino')
  • Nyssa sylvatica
  • Prairie Fire Crabapple (Malus 'Prairiefire')
  • Scarlet Sentinel Maple (Acer rubrum 'Scarsen')
  • Shumard Red Oak (Quercus shumardii)
  • Sunset Maple (Acer truncatum 'Norwegian')
Spacing, Sidewalk Cuts, Shading Calculations
  • Spacing: At least 20 feet apart
  • Sidewalk Cuts: Equal to at least 4 by 4 feet
  • Shading Calculation: +/- 300 square feet
Pruning Requirements
Prune all trees to provide at least 8 feet of clearance above sidewalks and 12 feet above street roadway surfaces.

Priority List of Trees to Retain
In order of priority, these trees are to be retained during development:

  • Ponderosa Pine
  • Incense Cedar
  • Sugar Pine
  • Douglas Fir
  • Black Oak
  • White Oak
  • Pacific madrone
  • Bigleaf Maple (Riparian only)
  • Oregon Ash (Riparian only)
  • Cottonwood (Riparian only)
Trees Recommended for Placement Under Power Lines
Small Trees - small or narrow trees (under 25 feet, less than 20 feet wide) may be spread at any interval 20 feet apart or greater. Sidewalk cuts equal to 4 by 4 feet or larger.
  • Eastern redbud (cercis canadensis)
  • Flame maple (acer ginnala)
  • Kousa dogwood (cornus kousa)
  • Thundercloud plum (prunus cerasifera "thundercloud")
Not Recommended for use as Street Trees
The following tree species are not recommended for use as street trees. The reasons are noted for each species. If the problems are satisfactorily met and accepted by the owner, and noted on the site plan, these trees may be planted.

Problems / Considerations
Big maple leaf
Acer macrophyllum
Roots cause injury to sewers and pavement
Betula spp Aphids, low branching, invasive roots, injury to sewers, pavements
Box Elder
Acer Negundo
Subject to wind damage
n/a needles, low branching
Fruit trees n/a Litter
Hawthorns Crataegus spp
Insects and disease prone, aphids
Mountain ash
Sorbus aucuparia
Large crop, messy fruits may be sidewalk hazard
Nut trees
n/a Litter
Red Alder
Alnus rubra
Short lived, brittle, favorite of the tent caterpillars
Silk Tree
Albizzia julibrissin
Litter, aggressive roots
Platanus spp London plane; vigorous roots, damage to sidewalks, sewers, serious anthracnose disease
Tree of Heaven
Short lived, invasive roots