Steering Toward Summer

On May 1, a small clump of Coreopsis blooming at the edge of a Brazoria County ditch brought an immediate smile. The combination of flower and buds looked remarkably like a ship’s binnacle, with its compass in the middle and correcting balls at either side.

Binnacle on the 1885 cargo ship Wavertree ~ South Street Seaport Museum

Local distortions of the earth’s magnetic field can make a compass inaccurate for navigational use, but some of the distortions, particularly those caused by the ship itself, remain fairly constant. Those errors are corrected by using small adjuster magnets, iron rods, or compensating balls incorporated into the binnacle, like those shown above. While the devices themselves also distort the local magnetic field around the compass, they’re arranged in a way that corrects compass headings.

The process of correcting a compass using various devices, called ‘swinging the compass,’ is complex. Even after adjustments are made, residual errors exist. So-called ‘deviation cards’ record known compass errors for all headings of the ship, and help to make accurate navigation possible.

Given our current conditions, I’d say this Coreopsis compass was perfectly adjusted; we’re making way, and the shore of summer is in sight.

 

Comments always are welcome.

A Little Spot of Sunshine

During a visit to the Brazoria Wildlife Refuge on September 29, 2019, I noticed a ditch filled with pretty yellow flowers. The colony was perhaps twenty feet long, and the low-growing plants held one bloom per stem. Less than an inch across, the combination of tiny ray flowers and conical disk flowers was cute as could be; the disk flowers reminded me of the radar domes found on boats.

As sometimes happens, it took time to identify the plant. It wasn’t until this fall that I recognized it as Opposite-leaf Spotflower. First named Anthemis repens by Walter Thomas in Flora Caroliniana in 1788, today it’s listed as Acmella oppositifolia (Lam.) R.K. Jansen var. repens or more simply as Acmella repens.

In the southern United States, Opposite-Leaf Spotflower grows on river banks, along pond edges, and in wet ditches. Its ability to survive occasional saltwater inundation no doubt helps it to thrive in Brazoria County, where I’ve now discovered it in every refuge, as well as in occasional country ditches.

As for identification, it was technology to the rescue. The only one of my field guides that mentions the plant is Ajilvsgi’s Wildflowers of Texas — where it’s called Creeping Spotflower — but I missed finding it there, and various keyword searches online didn’t turn it up. I tucked its photo into the “Unidentified Plants” file on my computer, where it lingered for months.

Then, after downloading the app called Picture This to my first iPhone, I decided to try taking a photo of the flower: not from its natural location, but from my computer file. Within seconds I had a name, and in only a minute or two more I’d found its image and details on a multitude of sites. It was a delicious irony. My pretty yellow phone — which I’ve named ‘Sunshine’ — had allowed me to spot the pretty yellow Spotflower at last.

 

Comments always are welcome.

Autumn Snow

Snow-on-the-Prairie

As summer begins to ease its grip on Texas, a lovely floral ‘snow’ suggests the coming of autumn. In the western two-thirds of the state, Snow-on-the-Mountain (Euphorbia marginata) covers much of the land. In the Eastern third (and north into Oklahoma), Snow-on-the-Prairie (E. bicolor) holds sway.

Snow-on-the-Prairie can grow to a height of three or four feet, and often forms dense colonies. Its long green and white bracts, open and airy, offer a pleasing counterpoint to surrounding grasses and forbs.

The plant’s long, slender bracts sometimes are mistaken for petals, but they’re actually  modified leaves. The flowers of Snow-on-the-Prairie are quite small, and exceptionally interesting.

Plants in the genus Euphorbia possess a unique structure called a cyathium (plural, cyathia) which contains both male and female flowers, as well as small structures known as bractioles, and nectar glands. Surrounding the flowers, bractioles, and glands, small bracts called cyathophylls — which superficially resemble the petals of a flower — provide additional color.

Here, the white cyathophylls of E. bicolor add to the plant’s ‘snowy’ appearance. Since the snow is only metaphorical, the sight is entirely pleasurable; it’s possible to admire this plant on the prairie without getting frostbite.

 

Comments always are welcome.

The Road Warriors

One of our earliest-blooming wildflowers, pink evening primrose (Oenothera speciosa) often covers fields, highway verges, and vacant urban lots with a dazzling combination of pink and white blooms. Despite its common name, the flowers sometimes open in the morning, inviting insects such as this tumbling flower beetle (Mordella sp.) to visit.

Despite their drought tolerance, these primroses don’t flourish in the temperatures of late summer; as the heat rises, the flowers begin to disappear from the landscape.

That said, I had to smile when I found this isolated group blooming away in the middle of a caliche road. Undeterred by late July temperatures or their less than perfect soil, they clearly deserved to be honored as botanical road warriors.

 

Comments always are welcome.

No Brook, but a Brookweed

The distribution of this tiny flower  — Limewater Brookweed, known scientifically as Samolus ebracteatus — is interesting. It can be found in every Texas coastal county save one, but after skipping a good bit of territory, it also appears in central Texas and the hill country before making its way west into a bit of New Mexico, where it’s sometimes known as Mojave Water Pimpernel.

The plant’s willingness to grow near springs and intermittent rivers in desert areas, as well as in the wetlands and salt marshes of coastal Texas, makes clear that Brookweed doesn’t require a brook in order to thrive.

Its flowers, measuring no more than a quarter-inch to a half-inch wide, appear on short stalks arrayed along a long wand. They mature from the base upward; as the season progresses, the plant continues to produce new blooms while fruits mature from the older flowers and release seeds.

The flowers of this in the Primulaceae (the Primrose family) attract the Southern Carpenter Bee, hoverflies, and butterflies. When I found this example at the Kelly Hamby Nature Trail in Brazoria County, other Brookweeds were being visited by an assortment of Sulphurs.

 

Comments always are welcome.