Tree & Site Selection
Right tree, right place
When selecting a tree species, think about how large the tree will grow over its lifetime and if your yard has the right sunlight, space and soil conditions to thrive. In particular, consider:
- Available space for tree branches and roots to grow. Trees should be planted 5 feet away from underground water, sewer and gas lines. Plant trees at least 10 feet away from utility pole, 20 feet away from streetlights, and 7.5 feet away from your driveway. Large trees should be planted at least 20 feet away from your house or other structures.
- Tree size at maturity. The larger your tree is, the greater the benefits it can provide. However, before you plant a large tree you should be sure you have enough space for it. Trees planted under power lines should be less than 25’ tall at maturity.
- Utilities. In addition to powerlines, trees should be planted at least 5 ft. from underground utility lines, 10 ft. from power poles, 20 ft. from street lights or other trees, and 30 ft. from a corner curb. To locate your underground utilities, be sure to call 811 to submit a dig ticket at least two days before you plan to dig.
- Evergreen or deciduous. Evergreen trees, which hold their leaves year-round, trap far more stormwater runoff than do deciduous trees, helping keep our waterways clean. When it's appropriate, consider planting an evergreen tree.
- Summer growing conditions. Does your site need a tree that can handle drought or flooding?
- Street tree permits. If your new tree will be in the planting strip or right of way, you need to apply for a free permit from SDOT. You can obtain a permit by calling (206) 684-TREE or clicking here. If you want help with the permitting process, consider participating in Trees for Neighborhoods.
- Non-invasive species. Select tree species without invasive tendencies in our region. Avoid English laurel (Prunus laurocerasus), English holly (Ilex aquifolium), European hawthorn (Crataegus monogyna), and tree of heaven (Ailanthus altissima). These trees are known to spread into Seattle's parks and open spaces and compete with native species.
- Maintenance. Consider the future maintenance requirements of a given tree. Fruit trees are great, but only plant if you're willing to pick up dropped fruit and leaves each fall.
Consider Planting a Large Tree
Large trees often become treasured neighborhood assets. Research has shown that large trees maximize the benefits in urban areas. They provide higher quality habitat for birds and other wildlife and they have larger root systems to help stabilize hillsides and prevent erosion. Large trees do more to buffer weather conditions, providing shade on hot days to reduce the need for air conditioning, and blocking winter winds to help save on heating bills. Studies have also shown that large trees even increase residential and commercial property values!
Large evergreen trees, especially conifers, are even better. Because large conifers grow so tall in our region, they produce a larger volume of leaf area on a smaller footprint – using the same amount of yard space but working harder to take in carbon dioxide, produce oxygen, and filter out air pollutants. And because evergreens hold their needles and leaves through the winter, our rainy season, they reduce stormwater runoff to a much greater extent than do small deciduous trees.
If you have the space in your yard or planting strip (away from overhead power lines), consider making a long-term investement in your neighborhood by planting a tree that will give back for decades!
Demystifying the Art of Tree Selection
Street Tree Planting List
Seattle Master Tree List
King County Native Plant Guide
Great Plant Picks
City Fruit's Guide to Best Fruits in Western Washington