Flower watching: The ox-eye daisy
Worth a closer look
Leucanthemum vulgare is so common we tend to pass it by. A native of Asia, it spread across Europe and eventually North America, perhaps brought by early colonists as seed heads in hay. It tolerates a variety of soil types, can withstand the hooves of heavy livestock as well as repeated mowing or grazing, and is extremely tolerant of drought and frost. A real survivalist.
Daisy and daisy-like “flowers,” like Fleabane, are actually composed of many tiny flowers. A daisy has two types of flowers: one is the so-called petal or “ray flower” and the other is the “disk flower” which is located in the central yellow “eye” of the daisy.
If you pull off the ray flowers (what we commonly call the petals) and look at the base of them, you will see a small yellow “y.” This is the female part of the flower and contains the ovary. The ray flowers have only female parts.
All of the disk flowers, located in what the “eye” of the daisy, are yellow, and they have both male and female parts. If you watch these disk flowers closely, the sequence of their opening is quite interesting. First, a tube comes out. This is the male and female parts fused together. Inside the tube, male parts shed their pollen which is then pushed out by the elongating female part. In the last stage, the female part elongates further and opens into a “y” shape at its tip. It has stayed closed until this time to avoid self-pollinating.
You can see this with the naked eye, but a magnifying glass improves the view. In the center of the yellow “eye” are the unopened disk flowers. Farther towards the edges you will find a circle of yellow pollen from the disk flowers in the male stage. The outermost disk flowers will appear soft with the open female flowers sticking out like little snake tongues.
All this careful orchestration makes great sense from the perspective of the plant. When a pollinator lands on the flower head, it lands at the outer edge of the flower and walks over the female parts of the ray flowers (the petals), exposing them to pollen from the flowers it previously visited. As the insect spirals inward, collecting nectar from each disk flower in the center, it also picks up the pollen which is sticky and adheres to the legs and body of the insect. In this way, daisies maximize their chances of cross-pollination.
Flower watching can be most gratifying, and unlike bird watching, the flowers stay put for some period of time and so observing them change over time is relatively easy. Of course, like everything, they are ephemeral, so enjoy these blooming days!
Ox-eye daisies and red clover by Darryn Kaymen. Close up of flower by Massimo Finizio.