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Oliver who writes:
>I've seen P besseae growing in Ecuador at ~6000 ft on a
northeast-facing granite cliff.
I am certain you have seen them there Oliver, this
sunny NE location is probably tolerated because enough water flows
past the roots. Most other species Phragmipedium that I have seen in Peru grow
in semi shade, usually on South facing slopes of valleys, or near rivers in the
shade of trees.
> I suspect that many species which are seen on cliffs not so much
from preference as that
> they are there because that is the only place that goats and other
browsers do not go.
This may be true in a specific habitat. If
indeed Phragmipedium species can have a preference, they are on certain
cliffs from the preference for water; the place where the Phragmipedium
seeds landed and were able to germinate due to the presence of
water.
Many cliff habitats of Phragmipedium species
have no goats grazing on the flats above the cliffs. Still, Phrags are only
found on the cliffs and not on the flats. They are on those
cliffs because of the abundance of water that comes tumbling down all
year. It creates a fog; high humidity and runs past the
Phragmipedium roots.
I have collected roots in those habitats, these are
usually very short and stubby for they do not have to search a large area for
nutrients.
The roots often showed an active symbiotic
relationship, for they contained live fungal coils in the act of forming new
pelotons. Thus it would appear that in addition to nutrients supplied by the
water, some nutrients are provided by the fungus.
peter
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