This is Butterfly Weed, Asclepias tuberosa.
The group of milkweed plants is the only food for Monarch butterfly caterpillars.
I love these plants because they are drought tolerant and deer-resistant.
The umbels of flowers are an eye-catching orange.
My favorite feature is the symmetry of the bloom clusters along the stem.
The umbel in the center matures first. Then the adjacent clusters next and so on outwardly.
This symmetry keeps the entire stem balanced.

I find this fascinating.
Form Follows Function.
Flower
Hadn’t noticed before how they open. Cool.
LikeLiked by 1 person
You have really studied this
LikeLiked by 1 person
Once a biologist, always a biologist. Thanks Knight.
LikeLiked by 1 person
Plants are amazing.
LikeLiked by 1 person
Love these amazing tidbits of info about a little amazing plant.
LikeLiked by 1 person
I had not noticed this! I will have to be more observant. We have two clumps of it in our bed at the shed. One is a deeper color, which I have never seen before.
LikeLiked by 1 person
I saw on as I drove by. Lovely!
LikeLike