Pretty accurate record of Epipactis gigantea. The colony I saw was actually from Santa Barbara County, not Los Angeles County.
I wouldn't doubt they'd be in LA County though, but not anywhere near the cities. They're most likely high up in the hills or in the mid-elevation mountain ranges.
The one I saw was growing next to a stream. Like the website says, it doesn't really matter what kind of forest it is, as long as it's cool and evenly moist, and there's a stream or river, they're most likely there in rather small numbers.
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Philip
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