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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!