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.

Not Recommended for Use as Street Trees
TreeSpeciesProblems / Considerations
Big maple leafAcer macrophyllumRoots cause injury to sewers and pavement
BirchesBetula sppAphids, low branching, invasive roots, injury to sewers, pavements
Box ElderAcer NegundoSubject to wind damage
Conifersn/aneedles, low branching
Fruit treesn/aLitter
HawthornsCrataegus sppInsects and disease prone, aphids
Mountain ashSorbus aucupariaLarge crop, messy fruits may be sidewalk hazard
Nut treesn/aLitter
Red AlderAlnus rubraShort lived, brittle, favorite of the tent caterpillars
Silk TreeAlbizzia julibrissinLitter, aggressive roots
SycamorePlatanus sppLondon plane; vigorous roots, damage to sidewalks, sewers, serious anthracnose disease
Tree of HeavenAilanthusShort lived, invasive roots