In early spring, the foot of the outcrop is beautifully clothed in blue, yellow, and white.
The bright blue belongs to Lupinus subcarnosus, the Sandylands
Bluebonnet. This species prefers sandy soils. Note that the
older flowers have red "eyes" on their banner petals. Bees cannot
see red. It is believed that the white-on-blue of unpollinated
flowers attracts bees while the red-on-blue of older flowers encourages
them to pass those flowers by. If true, this is a good means of
having the bees spend their efforts on unpollinated flowers.
The more-familiar white-tipped L. texensis (Texas Bluebonnet) is more often found on clay soils. Both share the honor of being the State Flower of Texas. Lupinus subcarnosus has more inflated "wings" (the lateral petals) than L. texensis and in the latter the immature terminal flowers of the inflorescence are more white.
Spiderwort (Tradescantia hirsutiflora, etc.), while not as plentiful as the bluebonnets, is a very striking blue and beautiful in its own right. With the right film, it photographs splendidly.
Much of the striking chrome yellow is due to thousands of little Denseflower Bladderpod (Lesquerella densiflora) plants. Each bears dozens of cross-shaped blossoms which will produce round green fruits. The fruits have two valves which fall off at maturity, leaving the replum, a central partition to which the seeds are attached.
A second species of Bladderpod, L. gracilis, also grows on the outcrop. This plant is much more typical of the Edwards Plateau region of Texas. This Grimes Co. population is believed to represent the easternmost extent of its range.
Halfshrub Sundrops (Calylophus
) also has bright yellow flowers. The blossoms last only a day,
here always seem to be plenty. These plants have very narrow, finely
leaves and are quite inconspicuous when not in flower. In
idntifying species of Calylophus,
it's important to observe the position of anthers and stigma. In
this species, the stigma is borne at or beyond the level of the
anthers; in other species, the stigma is farther down in the flower's
Parks Nailwort (Paronychia virginica) has yellow
too, but they are not very showy. The plants are small, with narrow,
A little later on, Berlandier's Flax (Linum berlandieri) adds its golden yellow to the palette. The orange-eyed blossoms are nice to look at but drop their petals almost the moment they are picked.
Several plants contribute white to the landscape in early spring. None of them has very large flowers, but sheer numbers make a beautiful display. Pitcher Sandwort (Arenaria patula, (image not yet available) is very uncommon in the area, except in sandy, rocky places like this. Its star-shaped flowers closely resemble those of the Drummond Sandwort (A. drummondii) but are noticeably smaller. Drummond sandwort is exceedingly common on sandy soils in East Texas in the spring.
Least Daisy (Chaetopappa asteroides) is quite common on the outcrop. Its common name is well-deserved--the flowers look like miniature daisies and the plant as a whole is very humble in stature. The ray florets tend to curl under as the flowers age. (Chaetopappa is the very small daisy-like flower in this image.)
Virginia Peppergrass (Lepidium virginicum), though not abundant, adds to the white on the outcrop. A member of the Mustard Family, its golden seeds can be used as a peppery spice in soups, salads, stews, and so on.
As we climb the side, more interesting plants come into view. Several of them are members of the sunflower family, the Asteraceae. Manystem Evax or Rabbit-Tobacco (Evax verna) is a small, silvery-gray plant that likes full sun and well-drained sandy soil. Its flowers are almost totally obscured by the dense hair that covers much of the plant.
The foliage of Flattop Wooly-White or Old Plainsman (Hymenopappus scabiosaeus) is also covered with whitish hairs, but its flowers are much easier to see. They can be white or pale pink and are all of the disk floret type. The phyllaries or bracts subtending the head have broad, petal-like margins which make the inflorescence even showier.