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Friday, May 15, 2020

Quercus with a Purpose

All oaks, like this Post Oak, are members of the genus Quercus.
Texas is home to dozens of native species of oaks, all of which are in the genus Quercus.  These trees provide humans with ample shade in the summer and beautiful color in the fall, and they sustain many mammals and birds with their acorn fruit.  But did you know that they are native host plants for dozens of butterflies and moth species, or the plants the female adults lay their eggs on for their caterpillars to eat?  In turn, the caterpillars of these butterfly and moth species provide a critical food source for almost all of the songbirds raising broods in the spring. Three of the most productive native oak species in central Texas are the Texas Live Oak (Quercus fusiformis), Post Oak (Quercus stellata), and Bur Oak (Quercus macrocarpa).

Texas Live Oak
The Texas Live Oak is also known as Escarpment Live Oak, Hill Country, and Plateau Live Oak.  Considered a semi-evergreen tree, the previous year’s leaves fall from the tree only when pushed out by newly emerging ones in early spring.  It has a stately mature form and unparalleled longevity, reaching to 40 feet in height with large limbs that over time spread an appreciable distance from the main trunk.  Firm textured leaves are oval to elliptical, 1 to 3 inches long, with young leaves having pointed lobes.  Its acorns are spindle-shaped or fusiform, narrowed at the base and ¾ to 1 inch long.  

Juvenal's Duskywing
Grote's Buckmoth
The Texas Live Oak is a host plant for Oak Hairstreak (Northern form), Juvenal’s Duskywing, and Meridian Duskywing butterflies, as well as Grote’s Buckmoth, Eastern Buckmoth, and Delilah Underwing moths.

Post Oak
Also known Iron Oak and Cross Oak, Post Oak is a deciduous oak to 50 feet, coarsely-branched with a dense, oval crown.  Its leaves are typically 3 to 5 inches long, with 4 pairs of lobes on each side, and the upper pair are often larger than the others, resembling a cross.  Acorns are ¾ to 1.25 inches long.  Post Oak is the most common oak throughout Texas, and its hard or iron wood is used for railroad ties as well as construction posts and timbers.  

'Northern' Oak Hairstreak
Polyphemus Moth
It is a host plant for the Oak Hairstreak (Northern form) and White M Hairstreak butterflies, and the Polyphemus, Eastern Buckmoth, Scarlet Underwing, and Little Nymph Underwing moths.

Bur Oak Acorn
Bur Oak is one of our largest oaks, also known as Savanna Oak, Overcup Oak, Prairie Oak, and Mossy-cup Oak.  A deciduous tree that can exceed 100 feet in height, its massive trunk supports heavy, horizontal limbs and lobed leaves up to 9 inches long.  Its acorns are the largest of all native oaks, up to 1.5 inches wide, with much of the acorn enclosed in a coarsely scaled cup with a heavily fringed margin. Sometimes spelled Burr Oak, it is the northern most oak in the New World, extending farther north than any other oak species.  

Banded Hairstreak 
Imperial Moth
Bur Oak is the host plant for the Banded Hairstreak and Juvenal’s Duskywing butterflies, in addition to the Ilia Underwing, Imperial, and Greater Oak Dagger moths.

While Texas is known for its oaks, care must be taken in identifying and maintaining oak trees.  Most all of the species can hybridize, occasionally making exact identification difficult,  and several of them are susceptible to oak wilt disease. However, they are worth the effort from a human and wildlife standpoint, as they are Quercus with a purpose!


Sunday, April 5, 2020

Blue Beauties

Blue Curls, Phacelia congesta
Spring brings a festival of color to our landscape in the form of wildflowers, mostly in shades of red, yellow, orange, purple, pink, and white.  But the most infrequent color of them all is blue.  There is no true blue pigment in plants, so they don’t have a direct way to produce blue color.  Plants have to perform a sort of trickery to produce blue blooms, using a common plant pigment called anthocyanin.  Plants have evolved to tweak their normally red to purple anthocyanin pigments by naturally modifying pH and then mixing those pigments, and combined with the way natural light reflects, these factors result in the creation of blue flowers.

Dayflower, Commelina erecta
Aside from the well-known bluebonnet, there are other blue beauties in bloom this time of year, including Dayflower (Commelina erecta), Blue Curls (Phacelia congesta), and Texas Bluestar (Amsonia ciliata).  Dayflower is a 3-foot high perennial with soft jointed stems that grow upright only if supported by other plants.  It blooms from May to October, but most frequently in spring or fall. The flowers are about 1 inch across, with two larger showy blue petals and one much smaller white petal.  Lasting only a day, several of these ephemeral blooms occur on one plant, generally one at a time, each opening 3 to 4 days apart.  Often found growing in dry scrub and partly shaded woods, its other common names include Widow’s Tears and White-mouth Dayflower.

Blue Curls, also known as Caterpillars, Fiddleneck, or Spike Phacelia, is a leafy annual or biennial that grows 1 to 3 feet tall in sandy or rocky soil.  Its periwinkle blue, bell-shaped flowers are ¼ inch long and occur in numerous slender, coiled clusters that uncurl as the buds develop, resembling the suckered underside of an octopus tentacle.  Its leaves are soft and deeply cut, often appearing ragged, borne on a brittle stem.  Blooming from March to May, Blue Curls is often found in large colonies in meadows and woodland edges.

Texas Bluestar, Amsonia ciliata
Growing up to 2 feet tall, Texas Bluestar blooms from March to June in dry open woods and on chalky hills.  Its narrow almost needle-like leaves occur singly but close together all long the stem up to the flower cluster.  Every cluster is made up of few to numerous pale blue flowers, each ½ inch long and wide, with a narrow tube opening into 5 petal-like lobes shaped like a star, with a ring of white at the center.  It is also known as Fringed Bluestar, referring to the fringe of small hairs found on the new leaves and plant stems. 

Less than 10 percent of the more than 280,000 species of flowering plants on Earth produce blue flowers.  Interestingly, while blue did not develop as a common color during the process of natural selection, plants that have blue blooms don’t seem to deter beneficial pollinators.  Both birds and insects can widely detect blue wavelengths, and blue flowers are just as capable of producing food as flowers of other colors. 


Friday, March 20, 2020

Risky Lilies


Death Camas amid the grasses
Primarily due to their inability to move around to escape danger, plants have developed an array of weapons to defend themselves against predators.  Some defenses are physical, such as thorns or stinging hairs, and others are chemical, mostly in the form of poisons or toxins.  After these harmful chemicals are produced by the plants, they are locked away in parts of the its cells called vacuoles, spaces within the cell that are enclosed by a membrane, protecting the plant from contamination.

The most common way that people or animals come in contact with poisonous plants is to accidentally eat them.  While we don’t normally eat the plants in our landscapes, widely planted ornamentals that are non-native and toxic include oleander, daffodil, elephant ear, iris, wisteria, and azalea.  Native plants can be toxic too, and there are two species in the Lily Family blooming this time of year that are fairly common but known to be toxic. They are Death Camas (Zigadenus nuttallii) and Crow Poison (Nothoscordum bivalve), and just their common names give them away!

The clustered flower head of Death Camas
Death Camas, also known as Nuttall’s Death Camas, Poison Camas, Poison-onion, and Poison Sego, is a perennial flower growing 1 to 2 feet tall, with narrow basal leaves up to 15 inches long.  A stout stem arises from a large, black-coated bulb, with a round-topped cluster of up to 60 cream-colored, 0.5 inch blooms growing around the top.  It blooms from February to April and is found in open prairies, woodland edges, and rocky hillsides in central and northeast Texas.  

Death Camas is a good early nectar source for butterflies
All parts of this plant are poisonous, even when dry.  While unpalatable, livestock has been known to eat it, but typically only in early spring when not much else is available.  While not in the same genus as edible Camas (Camassia sp.), humans have been poisoned, mistaking the bulbs for wild onion. 

Crow Poison is often mistaken for wild onion

Crow Poison, also known as Crowpoison and False Garlic, is one of the first flowers to appear in early spring throughout most of Texas.  Looking much like wild onion, it grows from a bulb but has fewer, larger white flowers about 0.5 inch across in loose clusters atop 8 to 16 inch stalks, and lacks the characteristic onion odor when crushed. Its basal leaves are narrow and 4 to 15 inches long, and it is found in lawns, open slopes, prairies, disturbed sites, open woodlands, and roadsides, where it often forms large colonies.  

Crow Poison blooms in loose clusters
When dug up, it will have a cluster of attached bulbs underground.  While this plant is minimally toxic to humans, it gets its common name from grain farmers’ past practice of crushing its bulbs and mixing them with a handful of grain to be left out for crows to eat.  In turn, the crows would get sick, with some dying, signaling the surviving crows to move on to other sources of grain. 

Now those are some pretty risky lilies!




Monday, March 2, 2020

Tree Serpents


Rough Greensnakes are excellent climbers.
One of the most beautiful and harmless snakes in Texas is the aptly named Rough Greensnake (Opheodrys aestivus).  Its genus is derived from the Greek ophios meaning ‘serpent’, and drys meaning ‘tree.’  It has a 22 to 32 inch long and slender bright green body, which fades to yellow or yellow-green on the sides near its abdomen.  Common to the eastern two-thirds of Texas, this snake is also colloquially called grass snake, green tree snake, and vine snake, but it gets its most recognized common name from its dorsal or topside scales, which are rough or ‘keeled’, having a ridge down the center rather than being smooth.

Primarily arboreal, the Rough Greensnake is found in open deciduous forest, pastures, and suburban gardens, most frequently those adjoining a watercourse such as a creek, stream, lake, river, or upland ravine.  It climbs into bushes, shrubs, and trees, favoring those with horizontal rather than vertical growth, both for protection and to forage for food.   It hunts crickets, grasshoppers, and spiders, as well as caterpillars of butterflies and moths.  Rough Greensnakes are diurnal, and they sleep at night coiled up on branches of vegetation.  Active most months of the year except for December through February, they take refuge in the cooler months hiding under rocks, logs, or debris.

Rough Greensnakes are also called 'grass snakes', due to their
bright green bodies that fade to yellow on their sides and abdomen.
One of the most curious facts about this snake, and others in this genus, is that they turn blue shortly after death.  Yellow pigment combines with blue pigment to give the snake its vibrant green color during life, but when it dies, the yellow pigment breaks down quickly and only the blue pigment remains.  Rough Greensnakes may be confused with Smooth Greensnakes (O. vernalis), but the latter, while similar in color, is shorter in length, has smooth dorsal scales, and occurs only as a relict population along the Gulf Coast of Texas.

While Rough Greensnakes become active as early as March, they mate in June and July, with females laying clutches of eggs in the second half of summer, typically in a depression under a flat rock.  Incubation is short – only 4 to 24 days – since embryonic development begins while the eggs are still in the female’s body.  These snakes can be most active in August or September, when the young emerge and are foraging for food, often in grassy lawns.  Be alert for these snakes when mowing grass at this time of year, as they are beautiful, harmless, and beneficial creatures!   

Saturday, February 8, 2020

Hardy Brushfoots

American Lady nectaring on Elbowbush
Winter is hardly a notable time for watching butterflies, except for those in the Nymphalidae family known as the brush-footed or brushfoots.  Most of these species are medium-sized to fairly large butterflies that hold their wings flat when resting and have a reduced pair of forelegs.  This group is also commonly called four-footed butterflies, because they are known to stand on only four legs while the reduced pair are held up against their mid-section or thorax. 

In some species, these shorter forelegs also have a brush-like set of soft hairs called setae, and it is unclear why these forelegs have become vestigial, or appearing to lose most of their ancestral function.  One theory is that these forelegs may be used to amplify the sense of smell (yes, many butterflies ‘taste’ with their feet!), while others believe they are used to improve signaling and communication between individuals of the same species, while standing on the other four.  The latter seems to be the leading theory so far, as that ability would prove most useful in terms of reproduction and the continuing overall health of the species.

More remarkably, brushfoots are experts at overwintering, or the process by which they pass through or wait out the winter season.  While many insects overwinter as eggs or pupae, brushfoots overwinter as adult butterflies.  They take cover in places such as building crevices, under loose bark, or beneath fallen leaves or other plant matter.  These places shield the brushfoots from the adverse conditions of winter, and their activity ceases until conditions become more favorable.  

Mexican Plum
Texas Redbud
On the occasional warm winter day in Central Texas, these butterflies often emerge to bask in the sun and feed on various nutritional sources such as tree sap, rotting fruit, or animal scat.  They are also found on early blooming native shrubs and trees, including Elbowbush (Forestiera pubescens), Mexican Plum (Prunus mexicana), and Texas Redbud (Cercis canadensis var. texensis), all of which are typically blooming in February.

A Red Admiral nectaring with its wings closed 
While many brushfoots are brightly colored on their upper sides, their undersides are largely dull and cryptic, mimicking dead leaves and bark, offering them additional protection in their chosen overwintering sites.  Examples of the most frequently encountered and easily recognizable brushfoots in our area include the Question Mark (Polygonia interrogationis), Red Admiral (Vanessa atalanta), Common Buckeye (Junonia coenia), and American Lady (Vanessa virginiensis).  

Question Mark
The Question Mark is fairly common in woodland openings, and is recognized by its deep orange wings spotted with brown and angled sharply at the edges.  Its cryptic underside is textured brown, resembling a dead leaf, and its hind wing is ‘punctuated’ by a curved silver line and dot also on the underside, which gives it its common name.  

A basking Red Admiral
Red Admirals are almost unmistakable, dark above with bright orange-red slashes and white dots on the outer part of the forewings, but intricately colored in mostly browns and blues below.  

A Common Buckeye warming in the winter sun
The Common Buckeye prefers open habitats, and can be identified by its overall golden brown color above, interrupted by large and striking multicolored eyespots.  

An American Lady resting on Elbowbush
Also preferring open or semi open habitats, American Ladies have an upper side with a mottled orange and brown pattern highlighted by white spots near the forewing tips, and the underside of the hind wings have two large eyespots in an olive background.  
The next time the weather is sunny and warmer, make a point to go outside and take a walk in the woods, a field or your garden, and see if you can find some of these hardy brushfoots!

Saturday, January 11, 2020

A Charm of Finches

Lesser Goldfinches feeding on sunflower seeds, one of their preferred foods.
At times, winter in Central Texas may seem a bit drab, colorless, and dreary, but the season is usually brightened by members of a beautiful and diverse group of birds called finches.  These small, seed-eating birds have an undulating flight, and flocks of them often roam south in the winter.

A male Lesser Goldfinch
Found primarily west of the Balcones escarpment, Lesser Goldfinches (Spinus psaltria) are present year-round, but are more likely to be seen at bird feeders in the colder months.  At 4.5 inches long, males have an entirely black crown and back, white wingbars, and are lemon yellow below, while females have olive backs, black wings with whitish wingbars, and duller yellow underparts.  They can gather in groups of up to several hundred at a time, and are most commonly found in Texas and California.

A male American Goldfinch
The American Goldfinch (Spinus tristis) is a slightly larger bird that is less common but typically present here from November to March. At 5 inches long, males have a bright yellow body, a black cap, and black wings with white wingbars.  Females are duller overall, with an olive body and black wings with prominent white wingbars. They are the only finch that molts its body feathers twice a year, in late summer and then again in late winter in preparation for breeding season.

A Pine Siskin
Most gregarious are the Pine Siskins (Spinus pinus), a 5 inch long finch with prominent brown streaking and yellow at the base of the tail and in flight feathers.  At first they may appear mostly grayish-brown, but they flash their yellow markings as they explode into flight or flutter while feeding.  Typically present from December through March, flocks of Pine Siskins may congregate at bird feeders one winter and be completely absent the next.  Their behavior is highly nomadic and their presence is erratic across North America in winter in response to available seed crops.  In fact, some individuals may stay near a dependable food source and breed far south of their normal breeding range, which is in Canada, the northern U.S., and higher elevations of the west.

While natural food sources are low in winter, these finches are most often seen at bird feeders that offer nyjer thistle and sunflower seeds.  Their conical bills are specifically adapted to pry open the outer covering of seeds, after which they shake their heads to loosen the husk, and then swallow the seed.  If you want to see these bright little birds at your feeders this winter, charm them by offering their favorite foods!

Saturday, January 4, 2020

Help Find Coco - Missing African Grey Parrot

REWARD:  Missing African Grey Parrot in NW Austin


While this is not a typical post for this blog, we feel we’d be remiss in not trying to get the word out on Coco, an African Grey parrot missing in Northwest Austin since November 24th.  Please read this post and keep a look out for Coco.  If you have any information that would be helpful in locating Coco, please contact her owner directly (contact information at the end of this post).


Coco, an African Grey parrot, is a silvery grey bird with red tail feathers.
She is about 13 inches long, with a wingspan of 18 to 20 inches.

Coco’s natural diet consists of fruit, vegetables, nuts, and seeds.
These parrots can live 40 to 60 years in captivity.  They are
companion birds that are prized for their intelligence and ability
to mimic human speech.

A flyer distributed around town describes Coco.  She is tame and
may be enticed by a grape and a bit of cheese. 

From Coco's Owner:


Coco has been missing since Nov. 24, 2019 in Austin, TX in the area TX Hwy 360 and Spicewood Springs Rd. Two weeks after her missing date she was seen twice on Courtyard Drive behind the Tennis courts and Scout Island drive, which is about 2 miles away from where she flew away.  Then, a few days later, an African Grey was spotted flying with a flock of Quaker Parrots in the 360/183 area - I am positive this was Coco.  When the temperatures drop at night, she will seek warmth. She may fly also into any openings like garages or porches, so please watch out for her. She may sit on fences, birdbaths, high branches, but maybe even around garbage cans seeking food.  If you find her, please approach her slowly. A piece of cheese, meat or fruit will entice her for sure. Speak to her softly, calling her name and SLOWLY approach your forearm to her. She will step up onto your arm and just look at you. Please avoid any sudden movements. That would startle her and make her take off again. Coco is not sexed, but I wanted her to be a girl, therefore "she".  She is a pretty healthy strong parrot with a decent vocabulary for a 10-year-old birdie.

I am offering a generous reward to the person who finds her and gives her back to me. I am still crying my eyes out, blaming myself endlessly... Thank you all for your generous support in helping me find Coco!!!

Sibyllehohendorf-shoemaker@hotmail.com
512-968-7587