Everyone knows the ox-eye daisy (Chrysanthemum leucanthemum). The flower’s bright yellow central disk is surrounded by white petals. It grows almost anywhere brightening hayfields, rural road sides, and even my gravel driveway. It’s almost as ubiquitous as dandelion.
Definition of summer
To me, ox-eye daisies are the wildflower that defines the beginning of summer. There are thousands of stems in my hayfield right now, and it blooms through September.
However, the ox-eye daisy is an invasive Old World exotic species. Normally, I wage war on exotics. I’ve battled multiflora rose, autumn olive, house sparrows, and starlings for decades.
But ox-eye daisy is just too beautiful to disparage. Its mere presence brightens the landscape, and it volunteers in even the most unforgiving soils. It has no detectable fragrance to my nose, so I just enjoy its visual appeal. Plus it’s a great cut flower so there are always at least a few fresh blooms in the vase on the dining room table.
Ox-eye daisies and relatives such as dandelions, asters, and sunflowers are just a few of more than 22,000 members of the family Asteraceae. Collectively they are often referred to as “composites.”
Curiously, a composite flower head, as the name suggests, is not a single flower. Composites are clusters of many small flowers. The yellow center is composed of many small disk flowers, each containing male and female reproductive parts.
That’s where the ox-eye’s seeds originate. The white outer petals are ray flowers and are usually sterile.
By observing ox-eyes, sunflowers or other composites over time, you can watch the individual disk flowers develop. The head matures over a period of days with the small disk flowers opening serially in an inward spiral. This insures that many different pollinators fertilize the disk flowers, which ultimately form seeds. This is how sunflower seeds are formed. That the Asteraceae is the largest family of flowering plants suggests that this is a very effective reproductive strategy.
Other familiar members of the Asteraceae include chicory, thistles, burdock, coneflower, Joe-pye-weed, hawkweed, colt’s foot, black-eyed Susans, goldenrods, and yarrow. Colt’s foot and dandelion are among the first blooms of spring. Many other composites are just beginning to flower.
Yarrow, for example, blooms all summer long. Yarrow is a dainty plant. The blossoms are small and lacy; the leaves are soft, feathery, and aromatic when crushed. The origin of yarrow’s scientific name, Achillea millefolium, requires some knowledge of history and Latin.
The generic epithet, Achillea, refers to the Greek hero Achilles. He reportedly used yarrow leaves to stop the bleeding of his soldiers’ wounds. The species name, millefolium, describes yarrow’s leaves. “Mille” and “folia” mean “thousand leaves” in Latin and refer to yarrow’s many finely divided leaves.
Thistles (genus Cirsium), by the way, are not the source of the “thistle” seed we buy to feed wild birds. Farmers loathe thistles, and consider it a noxious weed. Nyjer (Guizotia abyssinica), often erroneously called “thistle,” is actually a daisy-like composite grown commercially in Africa and Asia.
Like black-oil sunflower seeds, nyjer’s tiny black seeds are pressed for their oil for human use. And some goes to the bird seed market.
Of course, composites aren’t the only wildflowers blooming right now. Common milkweed (Asclepias syriaca) is an abundant roadside attraction. It is native, pleasantly aromatic, and an essential monarch butterfly host plant.
And butterfly milkweed (Asclepias tuberosa) started blooming few weeks ago. It is the most spectacular wildflower in my hayfield. Its brilliant orange blossoms breathe life into the field’s sea of green.
I’m always amazed at the variation in color from one plant to another. Some blooms are the brightest orange imaginable while others are almost an anemic yellow. Since such individuals grow side by side and are subject to the same soil conditions and rainfall, I suspect differences in flower color are genetic.
Freshly picked wildflowers make a great addition to any dining room table. A few butterfly milkweed and yarrow stems interspersed with a handful of ox-eye daisies can brighten the dullest room. Add a few common milkweed blooms for an intoxicating natural fragrance.