Montane, subalpine.  Streamsides.  Spring, summer.
West Mancos Trail, June 26, 2004.

When it occurs singly, Oxypolis fendleri goes unnoticed because it is quite slender and because its flowers, like those of its Osmorhiza cousins, are such tiny sprays of white, no more than two inches across for the entire flower cluster.  But O. fendleri becomes very noticeable when it gets wet roots and densely carpets high mountain stream-sides turning them white with hundreds of plants bearing thousands of flowers.  Heartleaf Bittercress, about the same height as Cowbane, also loves streamsides and produces masses of plants with many, but larger, and whiter flowers.  Oxypolis fendleri can even more easily be confused with Conioselinum scopulorum but the latter grows to be a more robust plant with larger flower heads and finely cut leaves reminiscent of Carrot leaves.

"Oxys", Greek for sharp and "polios" "white", refer to the bracts and white petals.  Augustus Fendler, 1813-1883, for whom a number of plants in our area were named, was, for a short time, a botanical collector for the renowned Asa Gray and George Engelmann.  (More biographical information.)

Montane, subalpine.  Streamsides.  Spring, summer.
West Mancos Trail, June 26, 2004.

Basal leaves are pinnate and oval to lanceolate in shape with slight serrations.  Their shape is quite different from the stem leaves shown below.

Montane, subalpine.  Streamsides.  Spring, summer.
Calico Trail, August 19, 2009.

The photograph shows stem leaves from two different O. fendleri that were growing near each other.  Notice that the leaflets on the plant at right have smooth margins; the leaflets of the plant at left have slight serrations.  These are common leaflet variations. 

Stem leaflets are in several rows, opposite, narrow, sometimes slightly serrated, and with a single terminal leaflet.   Each leaflet in the photograph is only an inch or so long.  There are usually but one or two clusters of stem leaflets and these are so small and cling so closely to the stem so that the stem at first glance appears to be leafless.  The shape of these stem leaflets is the easiest character to look for when trying to distinguish Oxypolis fendleri from Conioselinum scopulorum.