> Their study should not have any question about lack of proper
> controls.

But there will be questions about the feasibility of designing a
practical field experiment that will address all the questions.

Field studies are necessarily short snapshots and limited in sample
size.  Moreover, confounding factors are present from the start and
increasingly intrude over time.  Even in one season sufficient noise
creeps in to make any signal extracted somewhat subjective.  By the
second season there is little left to study that is unaffected by random
factors and error.

             ***********************************************
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