How do Maximilian sunflowers differ from common sunflowers?

Yesterday’s picture of a Maximilian sunflower, Helianthus maximiliani, at the Elisabet Ney Museum on August 28th might have made you think the plant could just as well have been a common sunflower, Helianthus annuus. One difference, as you see here, is all the long, slender, and oh-so-gradually tapering bracts beneath the head of a Maximilian sunflower. In contrast, the common sunflower has wide, relatively flat bracts that suddenly narrow only near their tips, something you can confirm in a picture posted here last year.

The background in today’s picture looks dark because I set the camera’s aperture to be small enough (f/14, for good depth of field) and the shutter speed to be fast enough (1/400 sec., to stop movement) that even the clear blue sky wasn’t bright enough to register well on the camera’s sensor with those settings. The same would have been true for the sunflower but I illuminated it with a flash, which of course had no effect on the sky.

© 2014 Steven Schwartzman