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I'm not sure where he got that information, but I suspect that in most
cases flies are not as efficient as bees. However, if overall visitation
rates by flies are higher (sometimes much higher) than those of bees,
flies as a group can end up transferring more pollen than bees.
<br><br>
<font face="Times New Roman, Times">Kearns, C. A. and D. W. Inouye
(1994). "Fly pollination of <i>Linum lewisii</i> (Linaceae)."
<u>American Journal of Botany</u> <b>81</b>(9): 1091-1095.<br>
<dl>
<dd><x-tab> </x-tab>This
study examines the reproductive biology of Linum lewisii Pursh.
(Linaceae), a polyphilic species visited by small bees and generalist
flies in montane Colorado. L. lewisii plants growing at different sites
experience large temporal and spatial variations in pollinator visits.
Their ability to attract both dipteran and hymenopteran pollinators
allows pollination under varying conditions as pollinator pool
composition changes. Although L. lewisii is self-compatible,
hand-pollination studies indicate that insects are required for seed
production. The relative effectiveness of fly and bee pollinators is
assessed in terms of per-visit pollen deposition. Insect visitation
patterns are combined with per-visit effectiveness data to evaluate the
relative importance of different pollinator groups. Overall, bees tend to
be more effective than flies in depositing pollen. However, in many
instances flies appear to be responsible for more pollen deposition due
to their higher visitation rates.<br><br>
<br><br>
<br>
</font><blockquote type=cite class=cite cite="">
</dl>Invite bees in and don't kill them off, beekeeper advises <br><br>
By STEVE BROWN <br><br>
Capital Press <br><br>
CENTRALIA, Wash. -- Beekeeper Robert Harris grudgingly admits that bees
may not be the best pollinators. <br><br>
"The common housefly is the most efficient pollinator," he
said, "but who wants them around?" <br><br>
With about 80 percent of crops dependent on pollinators, protecting them
is paramount, he said. <br><br>
Pollinators need no other encouragement to do their work, he said.
<br><br>
"It's most likely just the unintended conseq ...<br><br>
<a href="http://www.capitalpress.com/content/SB-small-farm-bees-031811-art">
Click here to read the rest of the story.</a> </blockquote></body>
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