Washington · Summer breeder

Tree Swallows in Washington

When tree swallows are present in Washington, when they nest, which native Washington plants feed them, and how to host them in a USDA 4a–9a yard.

Swallows (Hirundinidae)Tree SwallowTachycineta bicolor

Status in Washington: Summer breeder
Nesting window: May–June
Broods: 1 per season
Hardiness zones: USDA 4a–9a
Nest box: 1 1/2 in hole, 5 × 5 in floor, 5–10 ft

When to expect tree swallows in Washington

Tree Swallows are summer residents in Washington, arriving shortly before nesting begins in May and leaving after the young are independent. Through the season they feed on flies, mayflies and dragonflies.

Marine west-coast climate west of the Cascades, semi-arid shrub-steppe to the east.

Nesting in Washington

Across Washington, tree swallows typically nest from May–June. Nest site: nest box or tree cavity lined with feathers. Females lay 4–7 eggs, incubate for 11–20 days, and young leave the nest after 15–25 days.

Dry, sunny summers west of the Cascades; hot in the Columbia Basin.

Have boxes cleaned and mounted before April — tree swallows begin prospecting ahead of egg-laying.
Use a 1 1/2 in entrance on a 5 × 5 in floor, mounted 5–10 ft.
Fit a pole baffle or hole guard; ventilation gaps and drainage holes are essential.
Clean out old nests after each brood and again after June.

Native Washington plants that attract tree swallows

Of the regional native plants we track for Washington, these 8 provide food or cover tree swallows use:

Tall goldenrod

Solidago altissima · Perennial

Insect-rich in fall and seed in winter.

Paper birch

Betula papyrifera · Tree

Catkin seed feeds redpolls and siskins all winter.

Chokecherry

Prunus virginiana · Shrub

Dark summer fruit and heavy caterpillar load.

Ponderosa pine

Pinus ponderosa · Tree

Seeds and bark insects; pygmy nuthatch and woodpecker habitat.

Rabbitbrush

Ericameria nauseosa · Shrub

Late-season bloom supports insects; seed for sparrows.

Oregon white oak

Quercus garryana · Tree

Acorns and a rich insect community in the Pacific Northwest.

Douglas fir

Pseudotsuga menziesii · Tree

Seed for crossbills, siskins and chickadees.

Willow (Bebb)

Salix bebbiana · Shrub

Early catkins draw insects for arriving warblers and hummingbirds.

Feeding tree swallows through the Washington year

Tree swallows readily take bluebird-style nest boxes; mount boxes in pairs 15–25 ft apart to share with bluebirds.

Best foods: Crushed eggshells in spring.
In Washington's summer: offer water and insect foods; natural food is abundant.

Full diet breakdown for tree swallows · Best feeder for tree swallows

Frequently asked

Are tree swallows in Washington year-round?

No. Tree Swallows are summer breeders in Washington and leave for the winter.

When do tree swallows nest in Washington?

Nesting in Washington typically runs May–June, with 1 per season. Clutches are 4–7 eggs, incubated for 11–20 days.

What native plants attract tree swallows in Washington?

Tall goldenrod, Paper birch, Chokecherry, Ponderosa pine, Rabbitbrush, Oregon white oak, Douglas fir, Willow (Bebb) are native plants in Washington that provide food or cover for tree swallows.

What size birdhouse hole do tree swallows need?

1 1/2 in, with a floor of 5 × 5 in mounted 5–10 ft.

Other backyard birds in Washington

Black-capped Chickadee Purple Martin Downy Woodpecker Hairy Woodpecker American Goldfinch White-breasted Nuthatch House Wren House Finch Purple Finch Mourning Dove American Robin Dark-eyed Junco Song Sparrow Chipping Sparrow Northern Flicker Pileated Woodpecker Red-breasted Nuthatch Brown Creeper Red-winged Blackbird Evening Grosbeak Pine Siskin Common Redpoll Gray Catbird Cedar Waxwing Barn Swallow Yellow-rumped Warbler Eastern Kingbird American Tree Sparrow House Sparrow European Starling Steller's Jay Black-billed Magpie Canada Jay Mountain Chickadee Chestnut-backed Chickadee Bushtit Pygmy Nuthatch Anna's Hummingbird Black-chinned Hummingbird Rufous Hummingbird Lesser Goldfinch Cassin's Finch Spotted Towhee California Quail Western Bluebird Mountain Bluebird Say's Phoebe Bewick's Wren White-crowned Sparrow Golden-crowned Sparrow Fox Sparrow Varied Thrush Violet-green Swallow Black-headed Grosbeak Lazuli Bunting Bullock's Oriole Eurasian Collared-Dove

Sources

Timing reflects typical patterns for the region as a whole; local dates vary with elevation and year. Check the linked eBird bar charts for your county.