Finally, here is the number of bracts per raceme, which showed an almost
linear decline over time. The number of bracts is a measure of total flower
production on the raceme. Open flowers per raceme declines much more rapidly
than bracts per raceme. Thus, the decline in open flowers was caused partly
by a reduction in available flowers., and partly by the shortened longevity
of flowers after they are pollinated.
Strickler, K. and S. Freitas. 1999. Interactions between floral resources
and bees in commercial alfalfa seed fields. Environ. Entomol. 28(2):
178-187. Fig. 1B
