Hermann Müller was
the first to discover, by following honey-bees daubed on the thorax
with colored paints, that constancy is maintained not only throughout
a given foraging flight but also over a period of days. He thus
observed one marked bee to return repeatedly during 11 consecutive
days, and another during ten days, to the same plant of
Salvia aethiopis in his garden. 

Minderhoud subsequently demonstrated, from observations
of marked honey-bees on local patches of Taraxacum offcinale,
Trifolium repens and Reseda odorata, that, given an abundant
supply of flowers of one species, the foraging bee instinctively visits
an area about ten meters square.

The experience of the British seed trade tends to confirm this
view. That trade, faced during World War II with the problem
of maintaining uncontaminated the pedigrees of different vegetable
plants--turnips, radishes, and the like--while producing them in
mass on a crowded island, turned to an experimental study of
intervarietal crossing by bees. Crane and Mather concluded
that if a large mass of flowers were available, bees would
confine their visits to a small area. When radishes are grown in
quantity, for example, an interval of 300 feet guards against contamination
by intervarietal crossing. The 300 feet in this case is a
conservative isolation distance. Bateman found that the first
50 feet reduced the contamination to 1%.

Grant, V. (1950). The flower constancy of bees. The Botanical Review, 16(7), 379-398.

             ***********************************************
The BEE-L mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software.  For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html