Western Subterranean Termite

Reticulitermes hesperus · Order: Blattodea · Family: Rhinotermitidae

Can damage your home. They can damage wooden parts of houses, leading to costly repairs.

Source: UC IPM

Western Subterranean Termite
Photo: unknown, CC0

Reproductive termites have wings and swarm in warm, rainy spring and fall days (1,7,8). Workers are wingless, soft, and light caramel colored (2). These termites live underground in moist environments and are a major house pest in California (4,5,11).

Source: Wikipedia, UC IPM

How to recognize it

Only the reproductive adults have functional wings (1). Reproductive adults have yellow-brown or black bodies (3).

Source: Wikipedia, UC IPM

Is it a pest in the house?

Thousands of California homes need treatment each year for these termites (11).

Source: UC IPM

How to get rid of it

DIY pesticides are usually ineffective against termites (15). Consider non-chemical methods like wood replacement, heat, electrocution, or desiccants first (16).

Source: UC IPM

Where it lives

They live underground like other subterranean termites (4,9). They prefer moist living environments (5).

Source: Wikipedia

When you see it

Swarming occurs on warm days in spring and fall after rain events (8).

Source: Wikipedia

Where it comes from

Native to the coast from British Columbia to Southern California (6).

Source: Wikipedia

Lookalikes

Reticulitermes tibialis looks similar but is more common inland (12). Winged termites can be mistaken for flying ants (13). Check antennae, wings, and waist shape to tell termites from ants (14).

Source: Wikipedia, UC IPM

Where it is found in the US

Recorded in 9 of 51 states and DC. Most records: California, Colorado, Oregon, Washington, Idaho, Utah, Kansas, New Mexico.

Darker = more records. Counts are museum and citizen-science records, not population size.

Source: GBIF

Status: native in North America; native in Canada. Source: iNaturalist

Months it is reported in the US

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Source: GBIF

More photos

Western Subterranean Termite photo 3
Photo: unknown, CC0
Western Subterranean Termite photo 4
Photo: Kylie Etter, CC BY
Western Subterranean Termite photo 5
Photo: Garth Harwood, CC BY
Western Subterranean Termite photo 6
Photo: Kyle Elshoff, CC BY

Questions people ask

How can I tell if I have termites or ants?

Look at the antennae, wing shape, and the narrow waist; termites have straight antennae and a broader waist than ants (13,14).

Source: UC IPM

Same family (Rhinotermitidae)

Eastern Subterranean TermiteEastern Subterranean TermiteReticulitermes flavipesCan damage your homeFormosan subterranean termiteFormosan subterranean termiteCoptotermes formosanusCan damage your homeAsian subterranean termiteAsian subterranean termiteCoptotermes gestroiCan damage your homeDesert Subterranean TermiteDesert Subterranean TermiteHeterotermes aureusCan damage your homeMediterranean TermiteMediterranean TermiteReticulitermes lucifugus

Sources

  • UC IPM: https://ipm.ucanr.edu/PMG/PESTNOTES/pn7415.html
  • Wikipedia: https://en.wikipedia.org/wiki/Reticulitermes_hesperus

Look it up elsewhere: GBIF · iNaturalist · BugGuide · ITIS · Wikipedia

Text written 2026-10-22 from the sources above and checked sentence by sentence against them. Data fetched 2026-10-22.

How this page works

This is one bug's fact sheet. The colored box at the top says whether it is dangerous. Sections below cover how to recognize it, whether it is a pest, and how to deal with it. The US map shows which states have records; tap a state to see other bugs there.

Every fact on Bug FAQ comes from a named source (university extension sites, government agencies, GBIF, iNaturalist, Wikipedia). The source is linked next to each section. If we have no source for something, we leave it out.