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Showing posts with label Mountain Pink. Show all posts
Showing posts with label Mountain Pink. Show all posts

Saturday, June 29, 2019

Some Like It Hot

Eastern Ringtails, a type of Clubtail, obelisking.
The dog days of summer are upon us, and a long stretch of sultry weather lies ahead.  It can be a challenging time for people and for wildlife, but for some, it is their chance to put on a show. 

Bouquets of Mountain Pinks
Mountain Pink close up
Mountain Pink (Zeltnera beyrichii), also called Meadow Pink, Catchfly, or Quinineweed, is an annual herb less than a foot tall and best described as a neat bouquet of small, pink flowers.  Blooming May through July, Mountain Pink sprouts up like an inverted cone 8 to 12 inches high, on hot, rocky hillsides, limestone outcrops, and along gravelly roadways.  Its leaves are threadlike and are held below the multiple 0.5 to 1.0 inch wide showy pink five-petaled blooms that provide nectar for moths, butterflies, bees, and other insects.

Woolly Ironweed
Woolly Ironweed (Vernonia lindheimeri) is a 10 to 30 inch high clumping perennial, with woolly gray stems and long, narrow leaves.  Its bright purple flowers lack true petals, but the disk flowers are arranged in showy, terminal clusters.  A well-behaved species that should be used more often in gardens and landscapes, Woolly Ironweed blooms from June to September, and prefers open hillsides, roadsides, and fields offering full sun.  It is a good nectar source for many species of butterflies during the heat of summer, and is highly deer-resistant.

Blue Dasher, a type of Skimmer, obelisking
To prevent overheating on hot, summer days, some dragonflies and damselflies assume a handstand-like position called ‘obelisking.’  They raise their abdomens until the tip points up toward the sun, which helps to minimize the surface area of their body that is exposed to solar radiation.  Both males and females of these species will raise their abdomens when the temperature is high, and lower them again if shaded. Laboratory experiments have shown that this behavior is effective in stopping or slowing the rise in their body temperature.  This method of thermoregulation is practiced by about 30 different species in the Skimmer, Clubtail, and Broadwing Damsel families.  All are considered ‘perchers’ or sit-and-wait predators that spend a considerable amount of time stationary.

A sure sign that we are in the midst of a hot summer is the sound of cicadas buzzing in the air.  For their size, cicadas make as much noise as a large animal, and can be heard up to a quarter of a mile away.  In fact, the word ‘cicada’ is a direct derivation from the Latin meaning ‘buzzer.’  Many common species of cicadas in North America are in the genus Megatibicen  and are generally called the annual or ‘dog-day’ cicadas because they emerge every year in July and August, the dog days of summer.

Resh Cicada, Megatibicen resh
Male cicadas have structures called ‘timbals’ on the sides of their abdomens, and it is with these structures that they create their buzzy songs.  Unlike grasshoppers or crickets that rub their wings or legs together to produce sound, cicadas vibrate these timbals against their hollow abdomens, which amplifies the resonance of the sounds. They can even modulate the sounds by wiggling their abdomens toward or away from the tree trunk on which they are perched.  Each species has its own distinctive sound, and they use different mating songs to attract the appropriate mate.

Even in the heat of a long Texas summer, nature is busy going about its mysterious ways, offering sights and sounds that can recalibrate our senses, and allow us to continue to appreciate all that it has to offer.

Friday, June 16, 2017

Common Centauries


Mountain Pink, Zeltnera beyrichii

As members of the Gentian Family, there are many species of Centaurium worldwide, and three of them are native right here in Central Texas.  The genus was named after the centaur Chiron, famed in Greek mythology for being a great healer through his skill in using medicinal herbs. Herbalists today still use the extract from certain species in this genus, commercially often called ‘stomach bitter’, to aid in the process of digestion.  More recently, molecular studies have reclassified the genus, and the species that belong to the ‘Texas group’ have been renamed Zeltnera.

Mountain Pink (Zeltnera beyrichii), also called Meadow Pink, Catchfly, or Quinineweed, is an annual herb less than a foot tall and best described as a neat bouquet of small, pink flowers. Blooming May through July, Mountain Pink sprouts up like an inverted cone 8 to 12 inches high, on rocky hillsides, limestone outcrops, and along gravelly roadways.  Its leaves are threadlike and are held below the multiple 0.5 to 1.0 inch wide showy pink five-petaled blooms that provide nectar for moths, butterflies, bees, and other insects.  Pioneers used this plant as a medicinal plant to help reduce fevers, which is the origin for one of its common names.

Lady Bird’s Centaury, Z. texensis

Lady Bird’s Centaury (Z. texensis) is named in honor of Lady Bird Johnson, and is a delicate plant 3 to 7 inches tall with an open, branched habit.  Found in dry, grassy areas of the Edwards Plateau and Blackland Prairies, its leaves are linear and shorten in length on the upper part of the plant. Smaller than the other Centaurium species, its light pink five-petaled flowers bloom June to August, and are only about 0.25 inches wide.

Rosita, Z. calycosum

Rosita (Z. calycosum), also called Shortflower Centaury, Buckley Centaury, or Arizona Centaury, prefers moist, open areas in otherwise dry habitat, along streams, on hillsides, and in prairies and meadows with intermittent drainages.  An erect, branching plant up to 18 inches tall, it has larger, oblong leaves at the base and smaller linear leaves on the uppermost stems. Blooming May to July, the rose-pink five-petaled flowers are 0.5 to 1.5 inches wide, occur in an open array along the stalks, and have distinct, spirally curved, yellow pollen-producing anthers.  Of all three species in our area, this one is a bit less common.

Long used in herbal medicine, today’s science has discovered another interesting pharmacological feature of plants such as Centaurium in the Gentian family.  They naturally produce organic substances called xanthones that exhibit antioxidant properties, which are thought to inhibit microbial infection, inflammation, proliferation of cancer cells, and the aggregation of platelets, among other benefits.  Not a bad resume for these common centauries!