Pennsylvania · Summer breeder

Tree Swallows in Pennsylvania

When tree swallows are present in Pennsylvania, when they nest, which native Pennsylvania plants feed them, and how to host them in a USDA 5a–7b yard.

Swallows (Hirundinidae)Tree SwallowTachycineta bicolor

Status in Pennsylvania: Summer breeder
Nesting window: May–June
Broods: 1 per season
Hardiness zones: USDA 5a–7b
Nest box: 1 1/2 in hole, 5 × 5 in floor, 5–10 ft

When to expect tree swallows in Pennsylvania

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

Humid continental; cold, snowy winters in the north and mountains, milder in the southeast.

Nesting in Pennsylvania

Across Pennsylvania, 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.

Warm summers; bluebirds typically raise two broods.

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 Pennsylvania plants that attract tree swallows

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

Black cherry

Prunus serotina · Tree

Summer fruit and a major caterpillar host.

White oak

Quercus alba · Tree

Acorns and insects.

New England aster

Symphyotrichum novae-angliae · Perennial

Fall seed.

Flowering dogwood

Cornus florida · Tree

Fat-rich red fall fruit taken by thrushes, bluebirds and woodpeckers.

Serviceberry

Amelanchier arborea · Tree

Early-summer berries arrive exactly when nestlings are being fed.

Bur oak

Quercus macrocarpa · Tree

Drought-hardy prairie oak with large acorns and a heavy insect load.

American elderberry

Sambucus canadensis · Shrub

Late-summer berry clusters taken by over 40 bird species.

Arrowwood viburnum

Viburnum dentatum · Shrub

Blue-black fall fruit and dense nesting cover.

Feeding tree swallows through the Pennsylvania 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 Pennsylvania'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 Pennsylvania year-round?

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

When do tree swallows nest in Pennsylvania?

Nesting in Pennsylvania 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 Pennsylvania?

Black cherry, White oak, New England aster, Flowering dogwood, Serviceberry, Bur oak, American elderberry, Arrowwood viburnum are native plants in Pennsylvania 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 Pennsylvania

Northern Cardinal Eastern Bluebird Black-capped Chickadee Carolina Chickadee Purple Martin Downy Woodpecker Hairy Woodpecker American Goldfinch Tufted Titmouse White-breasted Nuthatch House Wren Blue Jay House Finch Purple Finch Ruby-throated Hummingbird Carolina Wren Mourning Dove American Robin Dark-eyed Junco White-throated Sparrow Song Sparrow Chipping Sparrow Red-bellied Woodpecker Northern Flicker Pileated Woodpecker Red-headed Woodpecker Yellow-bellied Sapsucker Red-breasted Nuthatch Brown Creeper Common Grackle Red-winged Blackbird Baltimore Oriole Orchard Oriole Rose-breasted Grosbeak Evening Grosbeak Pine Siskin Common Redpoll Indigo Bunting Eastern Towhee Gray Catbird Northern Mockingbird Brown Thrasher Cedar Waxwing Barn Swallow Eastern Phoebe Chimney Swift Yellow-rumped Warbler Pine Warbler Eastern Screech-Owl Wood Thrush Great Crested Flycatcher Eastern Kingbird American Tree Sparrow House Sparrow European Starling Fox Sparrow

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.