Phenomenal Phenology

 

The color-changing and dropping of leaves is a seasonal process.

Defined as the study of cyclic and seasonal natural phenomena, phenology is critically important in relation to climate and both plant and animal life.  The timing of biological events can be shifted earlier or later by climate variations in temperature, precipitation, and sunlight. Events such as migration, egg laying, flowering, and hibernation are all influenced by these climatic factors.  

Early blooming plants support early spring-emerging insects.

While ecosystems are resilient enough for normal phenological variations, major shifts may indicate a change in normal climate patterns.  These shifts can give rise to larger problems, since all life is interconnected.  In many areas of the world spring events are occurring earlier and fall events are occurring later than they have in the past. But since not all species are changing at the same rate or direction, mismatches are bound to occur.  

Nectar-producing flowers need to bloom in time for migrating hummingbirds.

Flowers that bloom too early leave fewer nectar sources for migrating hummingbirds.  Early flowering also leads to earlier fruiting, which typically yields lower quality fruit for fruit-eating migrating birds.  Many bird species time their nesting and egg-laying efforts so their eggs hatch when insects are available.  The emergence of insects depends on leaf out of their host plants.  One seemingly subtle shift in plant phenology can change entire food webs.  

Nesting and egg-laying are timed to coincide with insect emergence.

Some examples of phenology studies that are easy to perform include the date of emergence of flowers and leaves, the first appearance of migrating birds, the first flight of butterflies, the dates of egg-laying of birds and amphibians, and the date of leaf color changes and dropping in deciduous trees.  Studies can be formal or informal, and while many citizen scientists note these kinds of changes over the years, imagine if hundreds of thousands of them standardize their recording techniques and enter their data into a database that anyone can access.  This describes Nature’s Notebook, a web-based monitoring program of the USA National Phenology Network (www.usanpn.org). 

Anyone can contribute to the USA National Phenology Network's database.

Nature’s Notebook’s vision is to “provide data and information on the timing of seasonal events in plants and animals to ensure the well-being of humans, ecosystems, and natural resources.”  Its mission is to “collect, organize, and share phenological data and information to aid decision-making, scientific discovery, and a broader understanding of phenology from a diversity of perspectives.” Scientists use phenological data for critical applications such as understanding the timing of ecosystem processes like carbon cycling, assessment of vulnerable species and ecological communities, and invasive species and forest pest management.  Phenological data are immensely useful indicators of change, so considering joining the movement to document the changes you see in nature’s calendar, and watch what happens!

Preparing for a Winter Feast

 

Pine Siskin feeding on Thistle

Gardens can be a source of delight even during the winter months, if created with native plants for wildlife in mind. As the weather turns cold and foraging becomes more challenging, home gardens can be a critical resource for many different species.  Planting layers of vegetation, from ground covers to trees, provides the food and shelter necessary to sustain wildlife. 

Since different species utilize different types of food, it is important to consider the fructivores, nut eaters, granivores, and insectivores.   Native berry producing trees and shrubs that persist into winter are numerous and include yaupon, possumhaw, southern wax myrtle, American beautyberry, flameleaf sumac, roughleaf dogwood, Virginia creeper, Texas persimmon, and rusty blackhaw viburnum.  Trees such as the native Texas Red Oak, Live Oak, Post Oak, pecan, and Arizona walnut provide highly desirable nuts.  

Southern Wax Myrtle Berries

Rusty Blackhaw Viburnum Fruit

Post Oak Acorns

Another valuable practice is to create areas that mimic the forest floor by leaving leaves, which allows animals places to forage for overwintering insects.  Raking, mowing, and blowing is detrimental to many species of moths, butterflies, snails, spiders, beetles, and dozens of arthropods (such as millipedes).  Many moths and butterflies overwinter in the egg, caterpillar, or chrysalis/cocoon stage and use leaf litter as winter cover.  If you must keep your non-native lawn free of leaves, carefully rake them into a pile in the corner or spread them underneath trees and shrubs as a natural mulch.

Just as important is the practice of leaving seedheads and not cutting or pruning back perennials until they begin to break dormancy in late February or early March.  Birds can pluck seeds from spent flowerheads, hollow stems can become nests for solitary bees, and overripe fruits can be left to fall to the ground for animals to find.  Several native plant species that should be left standing throughout the winter include purple coneflower, blazing star, fall aster, common sunflower, tall goldenrod, western ironweed, frostweed, Texas thistle, Turk’s cap, blue mistflower, chile pequin, pigeonberry, and white boneset. 

Tall Goldenrod Seedhead

White Boneset Seedhead

Native grasses left to seed are also very beneficial, with clump-like vegetation at the base providing shelter from the cold and seedheads supplying food.  In early spring, the previous year’s leaf blades also provide necessary nesting material for many birds and small mammals.  The grass species to consider include inland sea oats, sideoats grama, switchgrass, big muhly, big bluestem, little bluestem, bushy bluestem, and indian grass.

Inland Sea-Oats Seeds

The colder months of the year are a good time to evaluate how well your garden provides a winter feast and haven for wildlife.  Helping our native animal species during the more barren months of the year by providing naturally occurring food and shelter helps to prepare them for a healthy and productive spring breeding season.

An Abundance of Acorns

Texas Red Oak displaying fall color.

Texas is famous for its oak trees, with over 50 different species found in the Lone Star State.  Each of these oak species produce acorns, also called oaknuts or mast, which is a collective term for fruits or nuts.  The word acorn is related to Gothic term akran which has been interpreted to mean ‘the fruit of the unenclosed land.’  When oaks are dominant in the landscape, as they are here in central Texas, they play an important role in the ecology of the forest.

Acorns usually contain one seed enclosed in a tough, leathery shell, and have a cup-shaped cap or cupule. Depending on the oak species, acorns can take from 5 to 24 months to mature.  As a general rule, acorns mature in late summer, turning green to brown, and start falling from oak trees in September and October.  Acorns produced by trees in the red oak family (such as Texas Red Oak, Quercus buckleyi) take two years to mature, while acorns produced by trees in the white oak family (such as Bur Oak, Quercus macrocarpa) only take one year. 

Texas Red Oak Acorns

Some years, known as mast years, trees produce copious amounts of acorns with smaller crops in the years between.  Scientists have proposed a range of explanations for the mystery of what might trigger a mast year, but they do know that it is not resource-driven as annual rainfall and temperature fluctuations are generally much smaller in magnitude than the variation in the crop sizes of acorns.  Some scientists hypothesize that masting trees are trying to maximize pollination efficiency.  If these trees flower and release pollen at the same time in order to increase their chances of reproduction, since large amounts of pollen correlate with larger amounts of germination, they ultimately produce more acorns.  Large, occasional outputs of seeds like acorns appears to be more favorable than frequent, smaller outputs.

Bur Oak acorns are our largest acorns.

Boom and bust years of acorn production actually benefit oak trees from an evolutionary perspective, because acorns are an important, highly nutritious food source for many animals including squirrels, mice, turkeys, blue jays, pigeons, ducks, deer, and bears.  In a mast year, these animals can’t consume all of the acorns produced, so some are left to germinate and grow into future oak trees.  In leaner years, animal populations are kept in check so there are fewer animals to eat the acorns in the mast years.  Over time, a higher proportion of acorns survive to become oak trees.

Copious amounts of acorns are produced in a mast year.

Too heavy for wind dispersal, acorns need other ways to spread beyond the mother tree into a suitable area for germination.  Jays, squirrels, and some woodpeckers serve as the main dispersal agents, as they gather and hoard acorns in caches.  While they are remarkable in creating mental maps of their cache locations, these animals rarely eat every single acorn, so a small number manage to germinate and produce the next generation of oaks.

The Blue Jay is one of many species that cache acorns.

As autumn arrives and acorns mature and fall from our oak trees, think of the potential in the abundance of acorns produced.  As Henry David Thoreau once wrote, “Every oak tree started out as a couple of nuts who stood their ground.”  

Cooling Conduct

Eastern Ringtail dragonflies obelisking

The unrelenting heat this summer has affected all living creatures, and while humans can escape into air-conditioned spaces, wildlife needs to rely on other ways to regulate their body temperature.  Often this is accomplished through different types of behavioral strategies acquired through adaptation, and some may seem quite odd until you understand the dynamics at work.

One of the most obvious behaviors (for humans at least), is sweating.  But many creatures don’t have sweat glands, or only sweat from their feet (like some canines), so they rely on panting instead.  In panting, animals breathe rapidly and shallowly with their mouths open, thereby increasing evaporation from the surfaces of their mouths.  This evaporation removes heat and acts as a cooling mechanism.  Panting is used by most mammals (like dogs) and many species of birds. While panting is effective at removing heat, dehydration is a risk so a nearby water source is important.  Birds may also spread their wings and body feathers to allow heat to dispel, and they have an elaborate breathing system that includes air sacs (in addition to lungs) to help them get rid of excess heat through panting.

A molting Northern Cardinal, panting and spreading its wings to cool down

Some birds, such as some species of vultures and storks, will voluntarily defecate on their legs to cool down.  Since bird poop is mostly liquid, it works by having an evaporative cooling effect, much like sweating.  As the poop dries on the bird’s legs, the heat is carried away and it brings down their body temperature.  Pelicans, herons, doves, owls, quail, and nighthawks, can employ gular fluttering, vibrating the muscles and bones in the throat and exposing moist throat membranes to the air, which helps regulate temperature by increasing evaporation.

Insects, like most all creatures, can also maintain a stable body temperature in at least a portion of their bodies through some interesting behavioral means.  While many insects need some heat to warm up their flying muscles, many will adjust/reduce their activity levels or seek out shady spots to handle extreme heat.  Dragonflies, for example, will often obelisk while perched in the midday hot sun, or point the tip of their abdomen directly up at the sun.  It is believed that this behavior reduces the heating effect by reducing the amount of surface area exposed directly to the sun’s rays.

Checkered Setwing exhibiting obelisking as a cooling behavior

When temperatures soar, four-legged animals such as squirrels, marmots, rabbits, bears, and even dogs and cats will lie flat on their stomachs on a cooler surface with their arms and legs stretched out from their bodies.  This behavior is called splooting, and it is thought that since their bellies have less fur and lots of blood vessels, they can dissipate the heat and absorb some of the coolness from the surface.  Also known as frogging or pancaking, splooting can take on various forms: the full sploot (all four legs out), the classic sploot (one leg tucked underneath the body while the other is kicked back), the side sploot (one leg tucked under the body and the other kicked out to the side), and the reverse sploot or toolps (when the animal lays on its back with its legs in the air)!

Fox Squirrel in a full sploot on our back porch

Regardless of the method, we all have to find some form of cooling conduct that allows us to survive until temperatures fall and (hopefully) the rains begin once again.

 

Black and White All Over

 

The white patches on the black body of this Cottonwood Borer
are actually areas of pubescence or short, dense hairs.

Colorful things typically catch our eye, but the patterns formed by black and white can often be the most striking.  In nature, these patterns can be achieved through contrasting chemical pigments or structural elements such as scales or pubescence (or hairs).  While somewhat rare but not uncommon, these distinct black and white combinations are particularly striking in three native beetles, the Cottonwood Borer (Plectrodera scalator), the Texas Click Beetle (Alaus lusciosus), and the Texas Ironclad Beetle (Zopherus nodulosus haldemani).

The Cottonwood Borer is an unmistakeable, robust, elongate beetle with a shiny black body up to 1.6 inches long, and irregular, contrasting markings of white pubescence.  It has long, black antennae and prominent spines on the side of the pronotum, or the plate-like structure that covers all or part of the thorax. As an adult it is most active in summer, feeding on leaf petioles (stalks) of cottonwoods, willows, and sycamores, and is often found near the base of these trees.  Its' larvae bore into the base of the tree, living under the bark, and require 2 to 3 years to reach maturity.

Cottonwood Borer, from above

Present in Central, South, and East Texas, the Texas Click Beetle, up to 2 inches long, has distinctive, large, round black eyespots its pronotum, usually encircled in white.  White markings made of scales on its black body are clumped and patchy rather than evenly dispersed, and can sometimes look faintly yellowish.  Its common name comes from the fact that they possess an unusual clicking mechanism, whereby a spine on the prosternum (the underside of the thorax) can be snapped into a corresponding notch that produces a violent click that bounces the beetle into the air.  It is mainly used to avoid predation but can be useful when it needs to right itself.  Its species name means ‘dim-sighted’, and it can be found under loose tree bark.

Texas Click Beetle

The Texas Ironclad Beetle, a nocturnal beetle up to 1.5 inches long, has a distinctively round pronotum and raised black bumps or knobs on a white body.  It has a phenomenally strong exoskeleton, very thick and hard, in part due to its interlocking elytra or wing covers.  As such, it cannot fly but will play dead for long periods of time if touched or disturbed.  Also called Haldeman’s or Southwestern Ironclad Beetle, the Texas Ironclad Beetle is endemic to East and Central Texas, and it is active as early as March and into late October.  It has been associated with dead or dying pecan, oak, and elm trees, and has been found feeding on lichen.  Each part of its scientific name has relevance; zopher comes from Greek and means ‘dark' or 'dusky’, nodulus comes from Latin and means ‘little knot' or 'knob’, and haldemani refers to Horace Haldeman (1820-1883), one of the first to concentrate on collecting insects in Texas.

Texas Ironclad Beetle

The next time you see a beetle that is black and white all over, take a closer look at these fascinating creatures.  You just might find them to be as interesting as their more colorful cousins!

Unfamiliar Passionvines

 

Birdwing Passionvine

While many flower and butterfly gardeners are familiar with the more common Passiflora species, namely Purple (P. incarnata), Yellow (P. lutea), and Stinking Passionvines (P. foetida), they are not the only species in this genus native to Texas.  Some of the unfamiliar native species include Bracted Passionvine (P. affinis), Corkystem Passionvine (previously P. suberosa now P. pallida), and Birdwing or Slender-lobe Passionvine (P. tenuiloba). 

The Bracted Passionflower is a climbing vine to 15 feet in length, with alternate, three-lobed leaves that is found growing in riparian to dry limestone areas of the Edwards Plateau.  The leaves are often appropriately shaped somewhat like cowboy hats. While similar to Yellow Passionvine, it is distinguished by having tiny nectaries on the underside of the leaves and small bracts or leaflike structures at the base of each flower. Each of these intricate flowers are pale yellowish-green to white and about 1 inch across with yellow fringelike segments purple at the base, and they can appear from May through October.  They produce small round berries 0.4 inches across that are green at first, but turn purple-black as they ripen.

Bracted Passionvine

Tiny dots on the surface of Bracted Passionflower 

leaves indicate the nectaries below, 

differentiating it from Yellow Passionvine

With stems up to 20 feet long, Corkystem Passionvine is naturally found in a few counties in South Texas, preferring subtropical woodlands and shrublands with rocky, sandy, and often calcareous soil.  Its common name comes from the corky bark it develops at the base of older stems. Alternate, three-lobed leaves are 1 to 4 inches long, somewhat glossy, and dark green.  Its 1-inch, complex blooms can be white, yellow, or green with a tinge of reddish-purple at the base of the yellow fringelike segments.  Blooming can occur any month of the year, eventually yielding bluish-black, slightly egg-shaped berries up to about 0.25 inches in diameter.

Corkystem Passionvine

The hardest-to-find small Passiflora vine is the Birdwing or Slender-lobe Passionflower (Passiflora tenuiloba). Growing on open limestone areas with dry, caliche soils, often over boulders or tree stumps mainly in the Edwards Plateau to South and West Texas, this vine can display quite a wide variety of leaf forms (compare the leaf shape the photo below with the one in the banner at the top of the post, for example).  While roughly symmetric, the alternate leaves are typically as wide as to usually wider than long, 3 to 9 lobed, and resemble the outline of a bird with spread wings. Its small, intricate blooms are 0.75 inches across, greenish-yellow with yellow fringelike segments that can be purple at the base.  Flowers can appear from April to December, turning into 0.35 inch wide dark blue to black berries.

Birdwing Passionvine

Birdwing Passionvine Leaf Variation 
©Doug Goldman, 2001, Cornell University

Most Passiflora species are host plants for longwing and fritillary (Heliconian) butterflies, such as the more common Gulf Fritillary and Variegated Fritillary, as well as the less common Zebra Heliconian and Julia Heliconian.  The larvae of these species feed on passionvines, and chemicals from these plants make the adults noxious to predators. 

The naming of the Passiflora genus of plants comes from the description of their intricate flower parts in the early 17thcentury by Spanish priests.  Known by the Spanish as La Flor de las Cincos Llagas or ‘The Flower with Five Wounds’, the passion flower refers to Christ’s suffering and its parts represent various elements of the crucifixion. The five petals and five sepals are the ten disciples less Judas and Peter, the corona filaments are the crown of thorns, the five stamens with anthers are the five sacred wounds, and the three stigmas are the nails by which Christ was bound to the cross.  While this symbolism is not universal, it is still an important reminder today in Christian societies throughout the world.

A Lady by Many Names

 

Lady Beetle Aggregation

Lady beetles, also known as ladybugs or ladybirds, are familiar insects that are part of the Coccinellidae family, which comes from the Latin coccineus meaning ‘scarlet’ and refers to their bright color.  The origin of their common names traces back to a European legend when farmers were said to pray to the Virgin Mary to prevent their crops from being destroyed by agricultural pests.  Commonly red or orange with black spots on their elytra or wing covers, their coloring serves as a warning to predators that they are not good to eat.

Lady beetles have a lifecycle that begins as an egg and hatches into a larva after 4 to 10 days.  The larvae are quite small, generally dark and alligator-like with three pairs of prominent legs.  They typically spend 20 to 30 days eating and growing until they pupate and then emerge as adults. Most lady beetles are active spring and fall, but can be encountered at any time of year.  During the winter, they gather in large groups called aggregations, to mate and protect each other from the cold during their hibernation period, as some can live as adults for more than a year. 

Lady Beetle Larva

There are more than 5,000 species of lady beetles worldwide, with many species imported from other countries.  This practice started in the late 1800s when an Australian species was imported to California for a pest control experiment which helped to triple the orange crop, so efforts were soon put in place to breed them.  Lady beetles typically eat several types of small, soft-bodied insects that are usually described as garden pests, such as aphids, whiteflies, scale insects, mealybugs, and spider mites. In Central Texas, the lady beetle species most commonly encountered are the Seven-spotted (Coccinella septempunctata), Spotless (Cycloneda sanguinea), Convergent (Hippodamia convergens), Ashy Gray (Olla v-nigrum), and Asian (Harmonia axyridis) Lady Beetles. 

Seven-spotted Lady Beetle

With a total of seven black spots on the red elytra and a black head with two white spots, the Seven-spotted is native to Asia and Europe, and was introduced specifically to control aphids.  Having no spots on bright red to orange elytra, and also called the Blood-Red Ladybird Beetle, the Spotless can often be found on milkweed species searching for aphids.  The Convergent has up to six small black spots on its red to orange-red elytra, white lines that converge behind the head, and are often found in aggregations.  The Ashy Gray comes in two color forms; the light form with ashy yellowish-gray elytra and few to numerous black spots, and the dark form with black elytra and two large red to yellow spots.  It feeds on aphids and jumping plant lice.  

Convergent Lady Beetle

Spotless Lady Beetle

The Asian Lady Beetle is highly variable in color and pattern, but typically has a marking that looks like a W or an M behind its head.  This lady beetle is sometimes called the Halloween Beetle, as it often invades homes to overwinter when the weather starts to cool in October.  Native to Asia, it is the most common and widespread lady beetle in North America, and is universally sold in the nursery trade for aphid control.

Asian Lady Beetle

Breeding Beauties

White-eyed Vireo nest, a sign of spring

As the fickle winds of  spring come in from  the south, they usher in several  species of birds  that spend the warmer months  in Central Texas.  Most of these species overwinter in Mexico, Central America, or South America, and their arrival in  our  area  signals  the start of the  breeding season.  Most notable  are the  Summer Tanager,  White-eyed Vireo,  Western Kingbird, and Scissor-tailed Flycatcher.

Summer Tanagers (Piranga rubra) are medium-sized, chunky songbirds with big bodies, large heads, and thick, pale, blunt-tipped bills.  Mature males are the only birds in North America that are completely red.  The female and immature males are bright yellow-green, which makes them harder to spot in the forest canopy. These birds prefer to stay fairly high in the trees, often in willows, cottonwoods, and mesquite along creeks and streams.  They prefer to sit still then fly out to catch insects in midair.  They are especially fond of bees and wasps, beating them against a branch once they are caught, but they may also forage on berries and fruits near their forest habitat.  Males have a sweet, whistling song, much like an American Robin.

Summer Tanager, male

Like most vireos, White-eyed Vireos (Vireo griseus) are small songbirds with compact bodies and thick, slightly hooked bills.  They have yellow spectacles around their white eyes, yellow-washed sides, gray head, white throat, and two white wingbars.  They prefer areas that are scrubby and thick with vines and other vegetation, staying hidden in the understory where they glean caterpillars and other insects. Their song is distinctive, rapid and harsh, sounding like ‘Spit. And see if I care. Spit.’ While only the males sing on their breeding grounds, both males and females have been found to sing on their wintering grounds.  They bathe by rubbing their bodies against dewy foliage in the early morning, or by quickly dipping their backsides in a pool of water.

White-eyed Vireo

Oddly often found in parking lots with Live Oak trees, Western Kingbirds (Tyrannus verticalis) are fairly large flycatchers with gray heads, broad shoulders, whitish chest, lemon yellow bellies, heavy straight black bills, and medium-length black tails with white outer tail feathers.  They prefer open habitats, often perching on power lines, fences, and in trees, waiting to hawk insects from the air.  In fact, their breeding range has been expanding as an unplanned result of humans planting trees and installing utility poles in open areas.  Their territory defenses include lots of wing-fluttering and a long series of squeaky, bubbling calls.  Paired males and females work together to defend their territory, which shrinks as the breeding season progresses.

Western Kingbird

Few birds are as graceful to watch as Scissor-tailed Flycatchers (Tyrannus fortificatus).  These elegant, slender birds are gray overall with salmon-pink flanks and underbellies, stout black bills, blackish wings, and long, forked tails they use to sharply twist and turn midair to catch insects.  Interestingly, Scissor-tails are known to use many human-made products in their nests, including pieces of cloth, paper, string, and even carpet fuzz and cigarette filters.  These items can account for up to 30% of the weight of the nests.  In late summer and early fall, these flycatchers gather to form large, bickering flocks and migrate together back to their wintering grounds.

Scissor-tailed Flycatcher

Scissor-tailed Flycatcher, showing its' namesake tail

The Real Rocky the Squirrel

 

Telltale signs of a Rock Squirrel Den

The squirrel family includes several different species that are grouped into tree squirrels, ground squirrels, and flying squirrels.  In central Texas, most are familiar with the Eastern Fox Squirrel (Sciurus niger) and the Eastern Gray Squirrel (Sciurus carolinensis), both of which are tree squirrels, meaning their habit is to live mostly among trees. The Southern Flying Squirrel (Glaucomys volans) occurs rarely in the eastern most portion of our area, and is named for the special flaps of skin on the sides of its body which allows for gliding flight.  But it is the Rock Squirrel (Spermophilus variegatus), which generally lives on or in the ground rather than in trees, that is our most notable ground squirrel.

Rock squirrels are stout, moderately bushy-tailed mammals, with mottled grayish-brown upperparts, a more brownish hind back and rump, buffy underparts, and a tail mixed with buff and brown and whitish tips.  The head and upper back are often distinctively blackish, and they have a light-colored ring around each eye. Adults are typically about 18 to 20 inches long, including the tail, and are found from central Texas westward into the Trans-Pecos region of west Texas.

Adult Rock Squirrel

As their common name implies, rock squirrels nearly always inhabit rocky areas such as cliffs, canyon walls, cervices, and rock piles, and even man-made areas like fills along highways and retaining walls.  These areas are where they seek refuge and create their dens.  Although they are typical ground squirrels, they can climb trees nearly as well as tree squirrels, where they can forage for berries and seeds, and they can scale rock walls with ease.  Their diet consists of a variety of plant materials, along with many types of insects.  Unlike many other squirrels, they are fond of flesh and can catch and eat small birds. They can survive long periods without water, some even up to 100 days.

Rock squirrels are facultative hibernators meaning they enter hibernation only when either cold-stressed, food-deprived, or both.   In central Texas they generally hibernate from November to February or March, often coming out to sun during warmer winter days.  Their populations tend to be colonial, each consisting of multiple breeding females and a dominant male.   Home ranges can be fairly large and include several different dens, and the males are thought to be polygamous.  Breeding occurs in March and April with an average litter of 4 young that emerge from the den in late spring.

A litter of 5 young Rock Squirrels

Most active in early morning and late afternoon, rock squirrels are rather shy and difficult to observe at close range. Like other ground squirrels, they are known for their tendency to rise up on their hind legs whenever they need to see over tall vegetation or when they sense nearby danger.  They then curl their front paws flat against their chests and send out a sharp, clear whistle to warn other family members if they sense the presence of predators.  Now you know more about Texas’ very own real-life version of Rocky the Squirrel!

Cool As A Cucumber

 

Another common name for Cucumber Weed is Pennsylvania Pellitory

In the middle of our Central Texas winter, one does not normally think of plants emerging from their cold weather slumber.  But one plant starts to appears in the cooler days of late fall through early spring, and it is appropriately named Cucumber Weed (Parietaria pensylvanica).

While native throughout much of the US and into Mexico, Cucumber Weed, also called Pennsylvania Pellitory, is generally considered an urban weed.  It grows in light shade with moist to slightly dry soil, mostly in disturbed areas along the sides of buildings, in suburban yards and gardens, and in woods and thickets. In fact, its’ genus name is derived from the Latin paries which means ‘wall’, which is where the plant likes to grow, presumably due to its affinity for alkaline soils. It is a member of the nettle family, but lacks the stinging hairs of most nettles and is considered unarmed.

The typical upright habit of Cucumber Weed

Cucumber Weed is 0.5 to 1.5 feet tall, typically erect and unbranched, and has a green, 4-angled, hairy stem.  Its alternate, simple, thin green leaves are lance-shaped, up to 3.5 inches long and 0.75 inches wide with smooth margins, although they are smaller on younger plants.  

The leaves of Cucumber Weed are hairy and have smooth margins

Small clusters of bracts and flowers appear at the axils of the middle and upper leaves.  Each tiny, almost indistinct, greenish-white flower is surrounded by longer green bracts, and the bloom period lasts from April to November. Flowers can be staminate (male), pistillate (female), or perfect (male & female), and these different flowers kinds of flowers can appear together in the same cluster. Cross-pollination occurs by the wind, and the plant reproduces by reseeding itself.  It frequently forms colonies and while it is a persistent plant, it is not aggressive like most invasive species.

Cucumber Weed's tiny flowers are surrounded by long green bracts

Often considered a medicinal herb for its diuretic ability reportedly used to help flush out kidney stones, Cucumber Weed is also high in potassium and edible, although caution must be taken as a small percentage of people may be allergic to it.  The early leaves of young seedlings offer the strongest cucumber taste, while leaves from older plants seem to lose some of their flavor.  Some use the raw leaves in salads or smoothies, or steamed and mixed with pasta. In an online database of indigenous plants of Mexico, Cucumber Weed is called Hierba del Rayo or ‘Lightning Herb’, as it was said that a poultice of this plant applied to your forehead overnight would relieve the chills, fevers, headache, and nosebleed resulting from a nearby lightning strike.

Red Admiral

Care should be taken not to completely remove Cucumber Weed from your yard or garden as it also has value to several types of wildlife.  It is a host plant for the Red Admiral Butterfly, whose caterpillars eat the soft leaves and create shelters from predators by tying up leaves at the end of a shoot or by folding over a larger leaf.  

Lincoln's Sparrow

Cucumber Weed is a source of seed for Lincoln’s Sparrows during fall migration, and there is evidence that White-tailed Deer like to browse the foliage.  Try to stay cool as a cucumber and resist the temptation to pull up Cucumber Weed, as this is one ‘weed’ that is useful to humans and wildlife alike!