Purple People Eater

Target Species: Purple Bladderwort (Utricularia purpurea)


Purple Bladderwort

This is one I have wanted to see for a long time.  Utricularia purpurea is an aquatic, carnivorous plant that inhabits much of the Eastern United States.  It barely enters Texas in the extreme southeast portion of the state, where it is rare.  I suspect that very few people have seen the Purple Bladderwort here, as the few known populations are not particularly easy to access.  Pursuing the photographs seen here was a true adventure, and the highlight of my 2017 quest for biodiversity thus far.


Purple Bladderwort

The Purple Bladderwort has a peculiar distribution, not unlike that of another species on my 2017 list, the Blue Lupine.  In the case of the bladderwort I suspect that its distribution can somewhat be explained by the presence of appropriate wetlands in the Gulf and Atlantic coastal plains, and in glacially formed depressions in the Northeast and Great Lakes regions.

Utricularia purpurea

County-level distribution of Utricularia purpurea from http://www.bonap.org.  Yellow counties indicate that the species is present but rare.

To see this rarity, I once again called on the good people of the Nature Conservancy of Texas.  Wendy Ledbetter, Forest Project Manager, told me that U. purpurea had been reported from a series of flatwood ponds on one of the properties they protect.  It was, in fact, very close to where I photographed Streptanthus hyacinthoides a few weeks ago.  She was kind enough to take time from her busy schedule to meet me one morning and show me the areas where it had been reported.  She brought me to two spectacular flatwoods ponds.  We were unsure if any of the elusive carnivores would be in bloom, but sure enough, after minimal effort I spotted one, then another, then another.


Purple Bladderwort

After showing me around for a couple of hours in the morning, Wendy had to leave to tend to other engagements.  I thanked her profusely, both for her time and consideration, and for the fine work that she and her colleagues at the Nature Conservancy have done to protect so much our great state’s incredible biodiversity.  After Wendy left I returned to the ponds to try to capture some unique images of this spectacular little plant.  I was trudging through water that was mostly between 1 and 3 feet deep.  To capture some of these images I had to sit, kneel, or completely submerge myself in the water, with just my hands and camera above the surface.


Purple Bladderwort

As previously mentioned, and eluded to in the title, Utricularia purpurea is a carnivorous plant.  It contains intricate leaves that float just below the water’s surface.  These leaves are loaded with small air-filled bladders that help keep the plant afloat.  Each bladder is equipped with a small, hair-like trigger. As tiny aquatic organisms swim by and brush against the trigger, the bladders instantly open, and as the water rushes in to occupy the vacant airspace, the organisms are sucked in.  The bladder then snaps shut, trapping them inside where they are slowly digested.  In the late spring through the summer the lavender flowers emerge from the depths.  U. purpurea is one of several species of Utricularia in Texas, but it is the only one with purple blooms.  The others are all yellow.


Purple Bladderwort.  If you look closely you can see some of the round bladders under the water.

The flatwood ponds in which I photographed the Purple Bladderwort that day were the finest I have ever seen.  These unique aquatic communities occur in clay-bottomed depressions where over the millennia water and organic material have accumulated.  Historically they were dominated by a variety of grasses and sedges, kept free from woody encroachment by regular wildfires.  In the modern era of development and fire suppression, however, high quality examples have all but disappeared.  They have persisted on this Nature Conservancy property, however, as a result of their excellent stewardship which includes frequent burns that penetrate into the ponds.  Scattered trees, mostly Swamp Tupelo (Nyssa biflora) exist on the margins, but the centers of the pond are open for acres.

Unfortunately I did not take any photos looking toward the center of the ponds, however I did capture the photo below looking back to the margins.  I found U. purpurea to be most common among the grasses and trees along the ponds’ margins.


Flatwoods pond margin

I spent what must have been at least 15-20 minutes lying on my belly, almost completely submerged in the water in order to get a low angle on a particularly attractive grouping of Purple Bladderworts.  After finishing I began to retrace my steps out of the pond.  As I did, I noticed something that was not there on my way in.  There was an 8-9 foot alligator laying on the bottom not 20 feet from where I was laying.  I suspect that its sudden presence was a coincidence, and that it hadn’t been slowly stalking me, but none-the-less it gave my heart a good jump.  Fortunately the water was shallow and clear, giving me a clear view of the magnificent creature, otherwise I was likely to have stepped on it.  I slowly made my way around it, and it never moved.  Though somewhat difficult to see, you can make out its head and part of its back in the photo below.


American Alligator

The Purple Bladderwort shared its ponds with its cousin, the Humped Bladderwort (Utricularia gibba).  Like Utricularia purpurea, it also relies on the bladders of its submerged leaves to obtain nutrients from animal prey.


Humped Bladderwort

There were several other interesting aquatic species in the flatwoods ponds, but the Floatinghearts (Nymphoides aquatica) really stood out.  It is also commonly known as the Banana Plant for its banana-shaped roots.





The flatwoods ponds were surrounded by a spectacular series of xeric sandhills occurring on ancient sand deposited by rivers as they changed course over time.  I spent some time exploring these beautiful communities, where I found a number of Eastern Prickly Pears in bloom.


Eastern Prickly Pear blooms in a xeric sandhill


Eastern Prickly Pear blooms in a xeric sandhill

I also took a moment to photograph the Pickering’s Dawnflower (Stylisma pickeringii), another species typical of deep sands, as it bloomed among the cacti.


Pickering’s Dawnflower

As if all of the above wasn’t enough, in the morning Wendy and I observed this Eastern Hognose Snake (Heterodon platirhinos) up to its anti-predator high jinks.  It spread the ribs of the anterior portion of its body creating a hood-like effect similar to that of a cobra.  This behavior has earned it the colloquial name of “spreading adder”.  Occasionally it would feign a strike, but never attempted to actually bite me.  Eastern Hognose Snakes feed primarily on toads, and have specially-adapted pointed fangs that can deflate toads that fill themselves with air in an attempt to make themselves larger to avoid being swallowed.  They also contain a mild venom that likely helps subdue their prey, though it is harmless to humans.


Eastern Hognose Snake


Eastern Hognose Snake


Eastern Hognose Snake

Seeing the Purple Bladderwort and exploring these incredible habitats is an experience I will never forget.  I can’t wait to return in the future to spend more time among the carnivores (large and small) of the Big Thicket.

Another Day, Another Sandhill

Target Species: Centerville Brazos Mint (Brazoria truncata var. pulcherrima)


Centerville Brazos Mint blooms among other rare plants in a high quality xeric sandhill

My pursuit of the Centerville Brazos Mint (Brazoria truncata var. pulcherrima brought me back to the xeric sandhills, the interesting community where I recently photographed the Smooth Jewelflower.  This time, instead of heading southeast to the Big Thicket, I traveled northeast to the transition zone between the Pineywoods and the Post Oak Savannah.  Here I found a community described by Texas Parks and Wildlife as “East-Central Texas Plains Xeric Sandyland.”

The Centerville Brazos Mint is rare.  The entirety of its range is confined to Texas, and it requires very specific conditions – deep sands with an open overstory.  These communities have declined dramatically since the colonization of Texas, and today very few high quality examples remain.  Fortunately I was able to visit some that likely appear as they did before Texas was settled.  Though they may be rare, where they occur, the Centerville Brazos Mint often thrives, forming carpets of pink over the sand.

Brazoria truncata var. pulcherrima is a member of the mint family (Lamiaceae) that is restricted to a handful of counties in East-Central Texas.  The genus Brazoria is named for the Brazos River, where it was first collected.  There are three species, all of which are endemic to Texas.


Centerville Brazos Mint

Where the Centerville Brazos Mint grows, other good things are sure to be found.  A suite of rare species occur in these sandhills.  Studies of these communities have found that they contain one of the highest levels of endemism in the Western Gulf Coastal Plain.  The day I visited I found another rare Texas endemic mint blooming in profusion – the Texas Sandmint (Rhododon ciliatus).


Texas Sandmint


Texas Sandmint


Texas Sandmint

I arrived early, and spent most of the day exploring the sandhills.  At around 4:30 pm I began to see flashes of deep pink.  I recognized them as the blooms of the Prairie Fameflower (Phemeranthus rugospermus).  Another rare species, it occurs in the Central U.S. from Minnesota to East-Central Texas.  It has succulent leaves, an adaptation for the drought-like conditions that occur in the deep sands that it prefers.


Prairie Fameflower

The Prairie Fameflower is so rare that it was once considered for listing under the Endangered Species Act.  It remains endangered on many state lists.  Most of the flowers I saw were a brilliant deep pink.


Prairie Fameflower

There were a few, however, that were a light, faded pink.  The flowers of Phemeranthus rugospermus open in the late afternoon, and only for a single day.


Prairie Fameflower

Portions of the sandhill were carpeted by the low, creeping forbs Yellow Stonecrop (Sedum nuttallianum) and Drummond’s Nailwort (Paronychia drummondii).  In some areas the two were growing together.


Yellow Stonecrop


Drummond’s Nailwort


Yellow Stonecrop

I also saw several Smooth Jewelflowers (Streptanthus hyacinthoides) in bloom.


Smooth Jewelflower

Prickly Pears were abundant in the deep sands.  The individuals here key to Opuntia cespitosa per the new treatment of the Opuntia humifusa complex by Majure, et al.


Prickly Pear


Prickly Pear

These sandhills occur in isolated pockets within a broader band of Post Oak Savannah uplands.  These savannahs were beautiful and diverse in their own right.  Though I didn’t have time to explore them properly during this visit, it gives me something to look forward to on my next visit.


Butterfly Weed (Asclepias tuberosa) blooms in a Post Oak Savannah


Jewel of the Sandhills

Target Species: Smooth Jewelflower (Streptanthus hyacinthoides)


Smooth Jewelflower

I have long admired the bizarre blooms of the Smooth Jewelflower, but had not previously sought it out.  Though it may be locally abundant, Streptanthus hyacinthoides is uncommon to rare in Texas.  A species of deep sands, it is most frequently encountered in the northern reaches of the Post Oak Savannah.  Globally it occurs from extreme southern Kansas and central Oklahoma through northeast Texas into northwestern Louisiana.  There are also a couple of disjunct populations in the Pineywoods: in the Big Thicket in Hardin and Newton Counties.


Smooth Jewelflower

It was here that I sought them out.  In the Pineywoods they occur in xeric sandhills.  In the literature, these unique communities are variably referred to as xeric sandhills, oak-farkleberry sandylands, xeric sandylands, sandhill pine forests, etc.  Here soil conditions inhibit the growth of many species.  The deep, coarse sands here ensure that even in times of high rainfall, the water percolates down through the soil very rapidly.  As a result, xeric sandhills exist with perpetual drought-like conditions, and only drought-adapted species persist.


Smooth Jewelflower

I was able to locate this population thanks to the help of my botanist friend Eric Keith, and Wendy Ledbetter, the Forest Program Manager of the Nature Conservancy in Texas.  Like so many more of our imperiled species, these rare jewels are protected by the Nature Conservancy.  I found them growing in a series of sandy clearings in a xeric sandhill dominated by Longleaf Pine (Pinus palustris) and Bluejack Oak (Quercus incana).


Smooth Jewelflower

I found the strange flowers somewhat difficult to capture.  I found them strikingly beautiful in their uniqueness.  Beyond habitat preference, I could find little on the life history of this species while researching my 2017 list.  It seems that there is still much to learn about this peculiar jewel of the sandhills.


Smooth Jewelflower

Xeric sandhills are also home to a variety of other unique and beautiful flowering plants.  Cacti and yucca, typically considered genera of the southwestern states, thrive here.  Traditionally the cactus species of this region was considered to be Opuntia humifusa, however recent work by Majure, et. al. is challenging that (More on that in a later blog post).  Using their new dichotomous key I keyed this species to Opuntia mesacantha.


Opuntia cf. humifusa

The beautiful Carolina Larkspur (Delphinium carolinianum) was also blooming in profusion.  I photographed the individual below from different angles, to see how the angle of light changed affected their color.


Carolina Larkspur


Carolina Larkspur

We also found the bizarre Large Clammyweed (Polanisia erosa) nearby.  I have heard the blooms described as miniature moose heads.  Large Clammyweed, like many species of xeric sandhills, is endemic to the West Gulf Coastal Plain.


Large Clammyweed

Butterfly Weed (Asclepias tuberosa) was also blooming in profusion.  This striking milkweed is common in sandy habitats throughout much of the United States.


Butterfly Weed


Butterfly Weed

Farkleberry (Vaccinium arboreum) is a conspicuous mid and understory component in xeric sandhills.  This blueberries produce edible fruits.  Though they are much smaller and less flavorful than what you might find in your grocery store, they still make for a refreshing treat while wandering across the parched sand.



Growing tangled among some of the numerous Farkleberries we found the twining stems of the Netleaf Leather Flower (Clematis reticulatus).


Netleaf Leather Flower

Xeric sandhills are certainly one of my favorite places to explore.  This post barely scratched the surface of the diverse flora that occurs here, and I didn’t even mention the many rare and interesting animal species that can be found in these deep sands, and I hope to revisit these special places in future blog posts.


Cacti bloom in a xeric sandhill