Re: missouriensis

My assumptions about the range of *Iris missouriensis* is based on climatological studies from land-locked lakes in the Basin and Range province in Oregon and Nevada.  Pollens identified in mud layers in the lakes show a pattern of movement of ecosystems north to south and back several times over the past tens of thousands of years, not unexpectedly, considering the known glaciation patterns and retreat-advance expectations based on other research and similar studies in Labrador.  *I. missouriensis* would have been expected to migrate both northward and southward with the drift of ecozones back and forth.  Isolated colonies in very high mountain valleys in either of the Sierra ranges in east and western borders of the central Mexican plateau would not be surprising even as far south as central Mexico.  Likewise, seasonally wet, but otherwise dry (xerophytic) grasslands in south-eastern British Columbia north of Christy Hensler's area may have similar isolated colonies.
 
There are some ecological anomolies in Oregon where one would expect all sorts of things in elevation bands that are curiously absent.  Apparently the rapid rise of block-fault mountains such as Steen's Mountain in southern SE Oregon generally south of Burns, OR, coincides with the most recent rapid advance northward of ecosystem zones, so that only those things that could be carried by birds--or, in one case, by early human movements in the area some 10 to 20 thousand years ago--would account for the presence of the plants found, as the mountain runs from 4000 feet at its base to just under 10,000 at its summit.  Flying from San Francisco to Boise the route followed on some flights allow the passengers on the left side of the plane to look out across a vast sea of clouds pierced very prominantly by the long, slanting but very steep eastern front of the block.  The western slope is very gradual, not preventing a road built directly up the mountain.  A good ranch pickup or jeep can travel right along going straight up the mountain.  It is a shock to find some very minor glaciated stream traces at the top but not a single Ponderosa Pine anywhere on the slopes below.  Aspen, yes.  Pine, no. 
 
Until continental drift was understood was the anomaly of the Steen's Mountain ecology explained.  One of the species expected is *Iris missouriensis.*  I believe it is entirely missing, not being capable of wind transfer, and unattractive to other birds as a seed source for food. It is found on valley floors relatively few tens of miles to the north in areas similar to those farther west near Bend and Sun River at similar elevations.
 
Neil Mogensen   z  7   western NC  mountains.

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