ANALYZING A PASSIONFLOWER BLOSSOM

As I was biking home a while ago I stopped to pick the blossom shown below from among roadside weeds. It's the flower of the weedy vine called Passionflower, Passiflora incarnata. This species is common from Florida and Texas north to Maryland, southern Ohio, southern Missouri and Oklahoma. It's a large flower, in real life about two-thirds the size of the picture, and in the wild it's even more spectacular than in the picture. So, how can you relate this exotic, frilly flower to the Standard Blossom?

In the picture above, do you see the three white things originating from the flower's very center? They are 3 spreading styles, each tipped with a pale yellow stigma. Remember that our Standard Blossom has 5 styles, not 3, so this is different. At the right is a cross-section view of the flower where you can see how the 3 styles arise from atop the egg-shaped ovary. In the picture at the right, below the ovary, the arching items are filaments, each filament attaching to the middle of a large anther. In the picture above you can see better how the filaments are speckled and come together like the arms of a star -- and there are 5 of them, just as in the Standard Blossom.

Now you have identified this blossom's sexual parts -- the stigmas, styles and ovary comprising the female pistil, and the filaments and anthers making up the male stamens.

You can plainly see in the cross-section that the Passionflower holds its male and female parts above the other parts, on a cylindrical tube surrounding a slender stalk below the ovary. This is something fairly special for the Passionflower family and certainly our Standard Blossom doesn't have it. In the large picture at the top of the page, it appears that the flower's corolla consists of ten petals. In reality, Passionflowers have only 5 petals. The five lobes not ending in green spike-like things are petals, but the five similar lobes that do end in green spikes are sepals comprising the calyx. This is a case where nature has made sepals look similar to the petals. If you could see the flower from behind, you'd observe that the backs of the petals are white, but the backs of the sepals are green. One point to notice is that despite the Passionflower's exotic appearance, it has five petals and five sepals, just like our Standard Blossom.

This leaves us with the very slender, hair-like items radiating from the flower's center, lending the flower much of its beauty. These are often called the "rays of the corona," and they are special growths our Standard Blossom simply doesn't have. Other flowers, such as Daffodils and Milkweeds, do have coronas arising between the calyx/corolla and sexual parts.

Having the sexual parts elevated above the calyx/corolla/corona, makes sense if you think in terms of the pollinator. In the cross-section picture, imagine a pollinator like a bee landing on the flower's "rays of the corona," then following the rays toward the nectar (here the rays serve as nectar guides). First the visitor deposits pollen on the overhanging stigmas, and after the visitor takes the nectar, as it leaves the flowers, it brushes against the overhanging stamens and gets dusted with more pollen, which it will carry to another flower.

ANALYZING A SILKTREE BLOSSOM

Now let's try matching the Standard Blossom with another flower, the one shown at the right. This is a branch off of a Silktree, sometimes called the Mimosa, Albizia julibrissin. This tree grows beside a road I bike down nearly every day.

First of all, with the above Passionflower we had no problems figuring out where the actual flower  was. With the Silktree, this question isn't immediately clear. You can guess that the broad pinkish area at the photo's left is the flower area, but not much here looks like our Standard Blossom. The trick is that the photograph shows several clusters of flowers. The first step with the Silktree, then, is to become clear what the actual flower is.

At the left you see a section of  a cluster of Silktree flowers shown above. At the top of the picture at the left, the fanlike thing occupying most of the picture is itself composed of several flowers. At the bottom left, one of the flowers has been removed, and in the pink-framed box at the bottom right you can see a separated flower's calyx and corolla. Now, what's in the box at least is beginning to look at least a little like our Standard Blossom!

The confusing and wonderful thing about Silktree flowers is that those long, slender, pinkish objects giving the flower clusters the appearance of being something like powder puffs, are stamens. Each flower bears 20 or more stamens, and each stamen is topped -- just as in our Standard Blossom --  by a tiny, yellow anther. The pistil's style is similarly very long and slender, and easy to confuse with the surrounding stamens.

So, all the parts of the Standard Blossom are present in a Silktree flower. It's just that the stamens are more numerous than usual, and the stamens and styles are much longer and more slender than usual.

Therefore... Wasn't it nice for a moment to have your mind thrust into the understuff of a Passionflower's blossom, and into the pink powder puff stuff of a Silktree's flower? And the main key you used to get to these fancy places was that of matching what you saw with the concepts embodied in the Standard Blossom.

That's how the Standard Blossom works, and why it's worth making the effort to use it.