Paul Kane on "Katchutequa"

[David D. Robertson]

In December of 1846 the artist Paul Kane came to Fort Vancouver, "the
Indian name of which is Katchutequa, or 'the Plain'," as he is quoted in
Diane Eaton & Sheila Urbanek's "Paul Kane's Great Nor-West" (Vancouver:
UBC Press, 1995, page 78).

This is the same as the Chinook Jargon word for Ft. V.:  Approximately
qitsutxwa or chutxwa.

By "Indian name", does Kane mean Jargon?  The word doesn't have any
meaning like "plain" or "prairie" in the varieties of Jargon I've seen.
Kinkade in his Upper Chehalis Salish dictionary terms it "from Chinook
Jargon", which begs the question of its source language.  The word must
come from a Native language where it meant "plain".  I don't find a
relevant root in Kinkade's dictionary.

Is it from Chinookan?

Incidentally, my search for an etymology for "katchutequa" led to a word
for "flat" in Upper Chehalis, cognate with CJ lhEq'Elh.  I hadn't been
conscious of that relationship.