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ENVIRONMENTAL BACKGROUND

The Iranian season for the collection of seeds of wild forage
plants generally occurs between May 1 and October 1.  This is a 
natural consequence of the winter-spring precipitation regime followed
by dry summer.  The season and collecting opportunities differ according
to elevation and relative aridity, rather than to longitude. The
following account considers them according to seasonal development
sequence under three nominal areas of elevation with relevant descriptive
notes on physiography, climate, and vegetation.  As the winter
range was not observed remarks are applicable to the summer range
only.  The former, judging from limited observations and ICA reports,
is of considerably less importance as source for forage introductions.
Animal subsistance on the winter range is mainly supported by the
quick winter-spring lowland annuals, shrub browse, and the stubble
feeds of cultivated lands.

The Lowland Area

During May and June seed maturation is to be found in the arid
lowlands only.  The early desert ephemeral annuals are the first and 
are followed irregularly by the perennials, some of which bloom early,
other late.  Species with desirable characters for introduction are
rare.  Among the common genera are Aegylops, Festuca, Bromus, Hordeum,
and Medicago, many of which are desired for genes rather than as
potential cultivates.  The seeding season for the early desert annuals
is short and below 3,000 feet elevation is about done by June 30.
        