Projectile point · Middle Archaic

Bitterroot

5500–2500 BCE, Desert Archaic, Plains Archaic

Bitterroot was defined by Swanson in 1962 from sites in the Bitterroot Valley of western Montana and the Salmon River country of Idaho, and it names the Middle Archaic side-notched horizon of the northern Rockies. It is closely related to Northern Side-notched and Mummy Cave. Local cherts, obsidian and quartzite are used.

ObjectProjectile point
Dates5500–2500 BCE
PeriodMiddle Archaic
CulturesDesert Archaic, Plains Archaic
RegionsNorth America — Great Basin & Plateau, North America — Great Plains

Diagnostic traits

Side-notched dart point with wide notches placed low, a straight to concave base that may form short ears, ground basal and lower lateral edges and a triangular blade.

Identification

Bitterroot's low notches separate it from Northern Side-notched, whose notches sit higher on the blade; Mummy Cave is the same idea on the Wyoming side and is separated mainly by region. Hawken has wider, shallower notches.

Reproductions and fakes

Not reproduced.

Cite this article

Stratum Study. "Bitterroot" (Artifact type). Stratum Study pack 2026.09, as of 2026-09-21. https://stratum.black/study/types/bitterroot. Accessed 2026-09-21.

@misc{stratum-bitterroot,
  title        = {Bitterroot},
  author       = {{Stratum Study}},
  howpublished = {\url{https://stratum.black/study/types/bitterroot}},
  year         = {2026},
  note         = {Artifact type article, Stratum Study pack 2026.09, as of 2026-09-21; sources: stratum. Accessed 2026-09-21.}
}

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Sources for this article: Stratum editorial (Stratum editorial). As of 2026-09-21; Study pack 2026.09. Data reproduced under the licences shown; text in Stratum's own words unless a section names its source.

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