I keep looking for non-insect subjects for stack focused macro photos - they are surprisingly hard to find. I noticed the grey headed coneflowers (Ratibida pinnata) in my prairie plant garden have started budding - so study of the flower bud and its wonderful spiral pattern that suggests the Fibonacci sequence: 

That photo is at 4.5x lifesized magnification - here's the full flower at 1x lifesized: 

Both images are focused stacked - the top image is made from 60 images in two separate stacks, which were then combined. The bottom image is made from 95 stacked images - I did not expect to need to stack so much for such a low magnification photo, but sheer depth of the subject - roughly 15mm - meant that it took a lot of images to get from front to back.