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Tuesday, March 31, 2015

Lovely Lupines


Texas Blubonnets, Lupinus texensis

Bluebonnets are often thought of as the ‘floral trademark of Texas’, akin to the shamrocks of Ireland, the cherry blossoms of Japan, the roses of England, and the tulips of Holland.  Loved for centuries, bluebonnets were described by early explorers as they roamed the vast prairies of Texas, planting them around the Spanish missions by early-day priests, and making them the subject of several Native American folk tales.  Technically known as ‘lupines’ or ‘lupins’, bluebonnets received their present-day common name due to the shape of the flower petals, which resembled the bonnets worn by pioneer women to shield their faces from the sun.

Bluebonnets are part of the legume or bean family, and like other members of this family they offer nitrogen-fixation through their root system’s symbiotic relationship with Rhizobia bacteria.  This gives them the useful ability to grow in poor, disturbed soils, and bring much-needed nitrogen back to these soils as they decompose.  Ironically, bluebonnets are all in the genus Lupinus, which is Latin for ‘wolf-like’, from the original but erroneous belief that these plants ravenously exhausted the soil.

In our area, bluebonnets normally bloom between March and April, but the timing and extent of the blooms depends on the amount of rain received the previous fall and winter.  The flower is purple to blue in color, about half an inch long, with a white spot on the upper petal or banner.  This banner spot acts as a target to attract the bumblebees and honeybees that pollinate the flower. When the pollen is fresh and sticky, the banner spot is white, and is seen by the bees as reflected ultraviolet light and appears to them as a good landing spot.  But as the flower and its pollen age, the banner spot turns yellow and then reddish-magenta, and is ignored by the bees, whose vision cannot see red.  The decline in bee populations has a direct effect on how many seeds a bluebonnet can produce, because bluebonnets cannot self-fertilize.  Each plant has the potential to produce hundreds of seeds, but often only a small number result, due to the recent decline in the number of bee pollinators.

A rare pink Texas Bluebonnet

Infrequently, both white, and more rarely, pink bluebonnets can occur naturally.  In fact, there is a legend associated with how the pink bluebonnet came to be.  Many years ago, in a spring wildflower field near San Antonio, children came across a pink bluebonnet on their way to Lenten devotion at the mission church.  Their grandmother told them the story of Texas, when it was a remote province of Mexico.  After a terrible Mexican dictator overthrew their Constitution, a war broke out between the brave new Texans and the Mexican troops.  The troops eventually overwhelmed the Texans, and much blood was shed and lives lost.  Several years later, the grandmother saw her mother place a pink bluebonnet in a vase by the statue of the Virgin Mary. She said she found it by the river, where “it had once been white, but so much blood had been shed, it had taken a tint of it.”  Interestingly, the only place in the state where the original native pink bluebonnets were found was along the side of a San Antonio road not far from the original mission. 

Big Bend Bluebonnet

Texas has 6 state flowers, more or less, and they are all bluebonnets.  In the spring of 1901, the Texas Legislature selected a state floral emblem after much debate and consternation.  Both the cotton boll and prickly pear cactus were hardy contenders, but the National Society of Colonial Dames of America won the day, and the Sandyland Bluebonnet (Lupinus subcarnosus) was selected and passed into law on March 7th.  And that’s when the bluebonnet war started.  The Sandyland Bluebonnet is a dainty little plant growing in the sandy hills of coastal and southern Texas, and many thought it was the least attractive of all the bluebonnets.  They wanted the Texas Bluebonnet (Lupinus texensis), which was a showier, bolder bloomer.  For the next 70 years, the Legislature was encouraged to correct its oversight, not wanting to get caught in another botanical trap or offend any supporters.  As politicians often do, they solved the problem with clever maneuvering by creating an umbrella clause, and in 1971 added the two species together, plus “any other variety of bluebonnet not heretofore recorded” (including potential species not yet discovered), and lumped them all into one state flower.

Long before the bluebonnet became the Texas state flower, many stories existed about its origins. Some believed it was a gift from the Great Spirit, and that it arrived with rain after a young, orphaned girl sacrificed her precious doll in the hopes of bringing a terrible drought to an end. Whatever you believe, look for these lovely lupines during our central Texas spring!    





Wednesday, March 25, 2015

The Buzz about Bees


There are over 1000 species of bees native to Texas, and this remarkable diversity is attributed to the high number of flowering plant species found in a multitude of habitats throughout the state.  Central Texas is home to at least 185 of these species, many of which inhabit our yards, gardens, and public green spaces.  Bees often get confused with other flying insects, mainly flies, wasps, and sometimes hawk moths.  Flies and wasps, in particular, have similar sizes, colors, and even stripes.  How can you begin to tell the difference?  


In general, bees have longer, thinner antennae, large eyes on the side of the head, four wings (although all four can be hard to see), at least partially fuzzy bodies, and can carry loads of moist pollen on their legs or abdomens.  Flies, on the other hand, have short, thick antennae, large eyes in front of the head, two wings, minute body hairs, and while pollen can stick to their bodies they don’t carry loads.  Finally, wasps have narrow bodies often with a pinched abdomen, very few body hairs, little to no patterns or designs in their exoskeleton, and like flies, don’t carry pollen loads.


Groups of bees that you will commonly see include metallic green bees, honey bees, bumble bees, and carpenter bees. Metallic green bees have an obvious metallic green exoskeleton, but care must be taken to use other methods of identification, as there are also metallic green flies and wasps.  Honey bees buzz as they fly from flower to flower, with a fuzzy thorax and striped abdomen, but while quite common and numerous, are a non-native bee imported from Europe.  


Our biggest native bees are the bumble bee and the carpenter bee.  Bumble bees have a robust body size and shape, mostly black with some yellow or white stripes.  Their entire body is fuzzy, and they fly around in a ‘bumbling’ pattern, making a low buzzing sound.  When landed, they fold their wings neatly over their abdomen.  Carpenter bees are mostly all black, some with a little gold or brown, and the top of their abdomen lacking hairs.  They are fast fliers, sometimes hovering like flies, and make a fairly loud buzz.  Upon landing, they keep their wings splayed apart.




Native bees could fill the important pollinator role currently held by the declining population of non-native European honey bees.  While there is still some debate as to the cause of this decline, there is no debate about the heavy reliance we have on bees pollinating many of our food crops.  Native bees offer an efficient alternative because they are resistant to the mites thought to be harming the honey bees, and because they do not live in collective hives but live singly in nest holes and tunnels, which are not at risk of being overcome by Africanized bees.  Further, native bees and their behavior have evolved so that their actions on a flower actually trigger pollination, so it is possible to find a native bee species that is evolutionally ‘tailored’ to assist a specific crop.  Now that’s something worth buzzing about!

Sunday, March 1, 2015

Spring Heralds


Texas Redbud, Cercis Canadensis var. texensis

Nature has a way of letting us know when spring has arrived in the hill country of central Texas.  In addition to increasing temperatures, the awakening of birds, butterflies, and native plants are among the harbingers that mark the arrival of the season.

More than half of the birds recorded in Texas are migrants.  Returning north in the spring to exploit the more productive temperate regions, they come in search of abundant food supplies, longer daylight hours, and less competition for nesting space. Texans have the advantage of being situated in the path of two flyways or principal routes used by North American birds – the Mississippi Flyway and the Central Flyway – and of the 338 species of North American species listed as Neotropical migrants, 333 are documented for Texas.

Chuck-will's-widows, Caprimulgus carolinensis, lay their eggs on the ground in the spring

Listen for the song of the Chuck-will’s-widow (Caprimulgus carolinensis), which sounds just like its name, rising up from the canyons in the twilight and pre-dawn hours.  Delight in the acrobatic flight of a Scissor-tailed Flycatcher (Tyrannus forficatus), a pearl gray and white bird with salmon-pink underwings and very long outer tail feathers, whose return coincides with the leafing out of the native Honey Mesquite (Prosopis glandulosa var. glandulosa) trees. Marvel at the nest-building skills of the Cliff Swallows (Petrochelidon pyrrhonota), who zoom down to creek beds gathering mud to build colonies of gourd-shaped nests under our bridges and overpasses.  And watch for the Western Kingbird (Tyrannus verticalis), a gray bird with a pale breast and yellow belly, whose raucous calls are heard in between bouts of insect-chasing from perches high in our neighborhood trees.

Scissor-tailed Flycatcher, Tyrannus forficatus

The sweet scents of early-blooming native plants catch our attention and the attention of many pollinating insects.  Some of the most fragrant include the Texas Mountain Laurel (Sophora secundiflora), whose glossy, evergreen leaves form the perfect backdrop for huge clusters of deep purple to whitish flowers, up to ten inches long, that smell like grape Kool-Aid.  Or the less common Mexican Plum (Prunus mexicana), a beautiful small tree identified by its numerous and intensely fragrant white blossoms, which like the pink blossoms of the Mexican Buckeye (Ungnadia speciosa) and the Texas Redbud (Cercis Canadensis var. texensis) and the yellow blossoms of the Elbowbush (Forestiera pubescens), appear on the tree before the leaves begin to emerge.  

Mexican Plum, Prunus mexicana
Elbowbush, Forestiera pubescens

Many of these native plants provide nectar for several species of bees, and are nectar and/or larval food sources for spectacular butterflies such as the Giant Swallowtail (Papilio cresphontes), Two-tailed Swallowtail (Papilio multicaudata), Great Purple Hairstreak (Atlides halesus), Juniper Hairstreak (Callophrys gryneus), Long-tailed Skipper (Urbanus proteus), and Henry’s Elfin (Callophrys henrici).

Henry's Elfin, Callophrys henrici
Juniper Hairstreak, Callophrys gryneus

Wildflowers will soon begin to grace our fields and roadsides, starting with the famous Texas Bluebonnet (Lupinus texensis), intermingled with Indian Paintbrush (Castilleja indivisa), pink Evening Primrose (Oenothera speciosa), Winecup (Callirhoe involucrata), and Indian Blanket or Firewheel (Gaillardia pulchella), to name a few.   These swaths of multi-colored gems not only delight the eye and provide the perfect setting for those upcoming Easter family photos, but they are a key element of the hill country ecosystem, and should be protected and propagated for the visual enjoyment and habitat value they provide all living things.          

Prairie Paintbrush, Castilleja purpurea var lindheimeri

As the weather warms, take the time to go outside and discover for yourself the distinctive essence of a central Texas spring.  As Lyndon Baines Johnson, one of our more famous Texans said, “The beauty of our land is a natural resource.  Its preservation is linked to the inner prosperity of the human spirit.”  Celebrate it!