The Nature Writers of Texas

The best nature writing from the newspaper, magazine, blog and book authors of the Lone Star State . . .

Sunday, February 26, 2006

Blackbrush Acacia Is in Full Bloom
by Ro Wauer

Blackbrush acacia, sometimes called "Chaparro Prieto," is currently in full bloom throughout much of South Texas. This thorny little tree or shrub possess white to light-yellow flowers that appear in cylindrical spikes; they can be so abundant that they literally dominate the branch. The leaves are alternate and compound, with two to four (rarely five) pairs of leaflets, and they possess straight spines. Most people, as well as bees, appreciate these lovely shrubs when flowering; they make especially good honey. However, like the closely related huisache trees, with their bright yellow and scented flowers, they can take over a field and be a problem to ranchers.

Four additional species of acacias, beside blackbrush and huisache, occur within the Texas Coastal Bend region. Catclaw (Acacia greggii) also possesses creamy yellow flowers that appear in cylindrical spikes, although it normally blooms from April to October. And catclaw spines are decurved, not straight like blackbrush. Fern acacia (Acacia angustissima) and guajillo (Acacia berlandieri) possess white to cream flowers that are rounded instead of cylindrical. Guajillo can flower most of the year, from February to December, while fern acacia flowers from April to October. Finally, twisted acacia or huisachillo (Acacia schaffneri) flowers are orange-yellow in color, very much like huisache, and bloom from February to April. They can be most common after spring rains. This last acacia differs from huisache by its spreading growth (not tree-shaped) and narrower and longer seed pods.

Acacias, all members of the legume or pea family, are widely distributed in warm regions around the world, where there are about 600 species; 300 occur in Australia. Ten species are native to Texas, and all of the Texas acacias flower in the spring and occasionally in the summer following rain. The genus Acacia means hard, sharp point, in reference to the prominent spines. All are semi-hardy and most are evergreen.

The legume family, or Leguminosae, is extremely large, with many representatives worldwide. Others in Texas include mesquite, mimosa, redbud, senna, retama, mountain laurel, and even clover and bluebonnets. Acacias and mimosas are often so similar they are difficult to tell apart. But the key difference is in the flowers themselves: acacia flowers possess numerous (20-100) stamens, while mimosas possess 10 to fewer stamens per flower. And mimosa fruits (pods) are flattened and somewhat contorted.
All these shrubs and trees are lovely when in flower!

Sunday, February 19, 2006

Are You Ready for Purple Martins?
by Ro Wauer

So what else can be expected earlier than normal this year? The weather has already produced a variety of early sightings, and now they include purple martins. But most of us may not be ready for these marvelous birds. So if you enjoy purple martins, clean up your martin houses and get them out so they can be utilized. Cleaning your houses means getting rid of the spiderwebs and insects that may have taken over since the rightful tenants vacated in midsummer of last year. If your houses are faded and worn, you may also need to give them a fresh coat of white paint. The light color helps to reflect the hot Texas sun and also to highlight the entrance holes.

In case this is your first time at attracting martins, here are some easy rules to follow:
* Houses must contain apartments with at least a 6 x 6-inch floor space and an entrance hole 1 ¾ inch in diameter and 1 inch above the floor.
* Houses must be placed on poles 12 to 20 feet above the ground and should be 40 feet away from taller trees, poles, and other structures.
* House must be free of nesting materials and other debris that accumulated in the off-season.

Purple martins often are rather finicky at the start but seem to put up with shorter poles and poorly maintained structures once the colony is established. Most birds are repeats, but the majority of the first-year birds (usually last year’s youngsters) seek out new sites, usually in the general area of the natal homesite. This means that a new martin house, especially it is it in the proximity of an active martin house, is likely to be used early on. Distant houses are not as likely to be selected.

Another way to attract first-year martins is to play a tape or CD of their dawn chorus. Playing purple martin songs at a new martin house will certainly attract their attention. And if they like their new digs, they will probably remain and nest. If not, give it time, and sooner or later you will attract martins that will begin a new colony.

An established purple martin colony is likely to return year after year so long as you maintain the house and environment. They will consume millions of flying insects, including mosquitoes and gnats, the short time they are with us. And they will also provide us with their marvelous songs from long before dawn to throughout the day and evening. But by mid- to late July they will leave our neighborhoods and begin their 5,000-mile southward migration to their wintering grounds in South America.

But rather than think about their departure, think first about their arrival. It is time to prepare. Good luck!

Sunday, February 12, 2006

Two Very Early Spring Butterflies
by Ro Wauer

Watch carefully for two of our earliest spring butterflies! Both are hardly noticeable, as one is very small and the other blends in so well to the vegetation that it is seldom obvious; it takes a concerted effort to see either one very well. The two species are the falcate orangetip and Henry's elfin. Both fly only from early February through March, and they cannot be found during the remainder of the year.

Falcate orangetip is a gorgeous little creature with a wingspan only about one inch. The upperside of this miniature white is mostly all white except for orange wingtips on males and a central black dot on female, females lack the orange wingtips. The forewing is slightly hooked, thus the name falcate. The underside of both sexes is mottled silver and black. When perched they fold their wings so their underside is visible. Yet they seem to spend most of their time on the wing, flying about searching either for a mate, in the case of males, or for specific larval foodplants, including rock cress, bitter cress, and a few other mustards, on which the female can lay eggs. Their flight is swift and constant and usually very low to the ground, so following one in anticipation of it landing to allow for a good look is seldom worthwhile; most observations are the result of a serendipitous sighting.

The falcate orangetip is the only orangetip that occurs in the eastern half of Texas, although it occurs throughout much of the eastern United States. Two other orangetips occur in the United States, but both are western species, just barely reaching Texas in Far West Texas, such as in the El Paso area. These two western orangetips, the Sara and desert orangetips, also are springtime fliers only, and can be expected in Texas only from February through April.

Henry's elfin, unlike the constantly moving falcate orangetip, is far easier to see once it has been located. It usually spends much of its time nectaring on flowers where it can be found crawling from one flower to the next. The difficulty in observing Henry’s elfin is that it often is easily spooky, flying away when approached, and it blends in so well with the vegetation that it can be hard to find. It is, however, considerably larger than the orangetips.

Being a hairstreak, Henry's elfins perch with their wings closed so one rarely sees the upperside, which is nondescript brown. The underside is also brown with darker bands with a tiny white spot at each end. The outer half of the hindwing is pale, giving it a frosted appearance, while the wing base can be very dark, even black. And the margins of the hindwings are scalloped. And unlike most hairstreaks, it lacks a tail.

Like the falcate orangetip, Henry's elfin is an eastern species, although it does range westward across South Texas to eastern New Mexico. Larval foodplants can vary from redbud to Mexican buckeye, to Texas bluebonnet, viburnum and American holly. Two other elfins occur in Texas, the frosted and eastern pine elfins, both known only in East Texas in the pineywoods area.

Besides the fact that both these butterflies fly only in spring, there is another similarity. Their tiny caterpillars hibernate most of the year. Orangetip females lay a single egg on each hostplant; they are able to detect an egg already laid on the host. But elfins may lay several eggs on a single hostplant. And the tiny caterpillars feed on the hostplant's flowers and leaves before going into the hibernation stage. But by early spring they become active and are soon flying about to the delight of all us butterfly lovers.

Sunday, February 05, 2006

Flowering Huisache Trees Are Early This Year
by Ro Wauer

One more indication of an early spring is the early flowering of the huisache trees. Already these little acacia trees are blooming in deep South Texas. Their sweet aroma is beginning to permeate some areas. Unless we in the Gulf Coastal area get some colder temperatures, we should expect that our area will soon follow suit. For those of us that appreciate these little aromatic trees, it is a thing to look forward to each year. But for some other folks, especially those landowners that already have trouble clearing their land for browse, huisache trees are only a pain. They are one of earliest invaders, and they seldom are utilized by cattle.

On the other hand, landscapes filled with flowering huisache trees are truly impressive. They seem to bright up the fields and pastures earlier than any of our other native trees. And because they bloom in such abundance all at once, with their blooms lasting for several weeks, they can literally dominate the area with their sweet aroma. It is, in fact, that marvelous aroma that appealed to some of the historic visitors to Texas. Texas huisache trees were introduced to Europe in the 17th Century, and cultivated trees were utilized in France as the base for Grasse perfumes.

Huisache plantations were established for cassie, as it is known in France, and a local strain that produces two crops each year was developed. The odor is extracted from the flower oils and concocted into a pomade which goes into extracts of violet and aromatic vinegar to produce a very concentrated material known as quintessence of cassie. It is one of the most costly of all scents.

Huisache, pronounced "wee-sach" or "wee satch-eh," is a small tree or a large shrub, rarely more than 25 feet tall, with a spreading rounded or flattened crown. However, the national champion huisache, near Rio Grande Village in Big Bend National Park, measures 48 feet tall with a 60-foot crown spread and a 6.1-foot girth. Like all other legumes (members of the pea family), huisache trees sport sharp spines; they are paired, straight, 1-3 inches long, and appear at the base of each leaf. Also like most peas or legumes, woody pods appear in summer or early fall.

The dark brown to black pods are 1-2 inches long and contain two rows of shiny, hard, gray seeds. Unlike mesquite pods, they are rarely utilized for food. However, according to Paul Cox and Patty Leslie in Texas Trees: A Friendly Guide, the "pods were formerly made into ink, the juice was used as a glue for mending pottery, and the bark for drying skins." What's more, "decoctions from the green fruit serve as an astringent and the roots were made used as a treatment for tuberculosis. Wound dressings were made from the crushed leaves, and the flowers were used as an infusion for ingestion and as an ointment for curing headaches."

Today our lovely huisache trees, rarely used at home for their assortment of benefits, but so well known elsewhere in the world, are among the greatest joys of spring. They are marvelous harbingers of the new, fresh season.

Wednesday, February 01, 2006

Cross Timbers Wildlife News

Jim Dillard, Wildlife Biologist, Texas Parks & Wildlife Department , Mineral Wells

If you spend any time at all hunting, fishing or just messing around small ponds or large lakes here in Cross Timbers Country, sooner or later you’ll encounter a helldiver. Although they probably don’t dive deep enough to justify their moniker, these small waterbirds are the Houdini of the bird world. Get too close and they’ll literally vanish right before your very eyes, leaving only a “now you see me, now you don’t” ripple on the water. They’ll usually pop back up close by a few seconds later with just their head showing above the water to make sure the coast is clear. If not, they’ll slowly sink back below the surface like a submarine and swim underwater to a safer location.

Although grebes (a.k.a helldivers) are duck-like in appearance, ducks they’re not, rather small waterbirds in the Family Podicipedidae. They’re found on all continents except Antarctica. Of the 20 species worldwide, seven can be seen in Texas but only the pied-billed grebe (Podilymbus podiceps) is a common year round resident here in Cross Timbers Country. This species is the most widespread in North America. During the winter, northern pied-bills drift southward to open waters ahead of the snow and ice. Their migration is mostly at night. If you see a grebe here in Northcentral Texas, chances are it’s a pied-billed. Other common names include dabchick, water witch and didapper.

Pied-billed grebes are adapted to a life on and under the water. Anatomically speaking, they’re built for diving with legs positioned well to the rear of their body and contained within the body skin: podiceps means “rump footed.” On land they can barely get around. Widely lobed toes provide extra propulsion underwater. Dense feathers make them waterproof and are held tight to the body when swimming underwater. Highly sought after “grebe fur” feathers were once in demand for use in making women’s hats, muffs and handbags. Somehow, they’re able to regulate their buoyancy to slip below or rise to the surface whenever they take a notion.

The short white bill is chicken-like with a black stripe during most of the year (pied means multicolored and refers to the variegated coloration of the bill.) On profile view, their head is relatively large and the body stocky. Around each brown eye is a distinct white eye-ring. Overall feather coloration is brownish-gray. Their call is a loud cuck-cuck-cuck, cow-cow-cow, cow-ah-cow-ah which surely must mean something special but only to another helldiver. Males and females look alike and average weight is 15.6 ounces.

Other than to escape predators or long-legged wildlife biologists, pied-billed grebes dive underwater in search of small fish, crustaceans, tadpoles, leeches, mollusks and some aquatic plants. About half their diet is made up of aquatic insects. Other foods include salamanders, spiders and frogs.

Pied-billed grebes are solitary and don’t prefer the company of other helldivers except during the breeding season. Once a mate is located, they’ll assemble a floating pile of vegetation for a nest site where four to seven pale blue eggs are laid. The nest is usually constructed in water deep enough so that it can be approached from underwater by the adults. That way, they can come and go from their nest without arousing the attention of predators. Eggs often become stained brownish from the damp, decaying materials in the nest. When eggs are not being incubated, they’re covered with vegetation until the birds return. Both parents help incubate the eggs for about 23 days and then feed the young a diet of aquatic cuisine. Although the black and white striped babies can swim soon after hatching, they’ll often climb on mom’s back for a rumble-seat ride, even holding on during underwater dives. First flight is at 35-37 days. One or two broods per year may be raised.

Pied-billed grebes often eat their own feathers and also feed them to their young. Although it’s not known for sure why they do this, feathers are thought to help protect their stomach in the digestion of sharp fish bones or other hard to digest food items. I guess this is just another one of those questions we’ll have for the Man upstairs someday.

During World War II, several U.S. Navy squadrons flew the Curtis SB2C dive-bomber nicknamed the Helldiver. Some pilots called them The Beast, others the S.O.B Second Class because of the airplane’s poor handling, stability and overall performance. Over 7,000 were built and effectively used against enemy shipping and bases in the Pacific Theater of battle. Many of these planes and their pilots were lost during the war. Today, only one flying plane remains in the Confederate Air Force.

Fortunately, our Cross Timbers Country helldivers are flourishing due to Mother Nature’s perfect design. All we have to do is just provide their habitat by keeping water on the landscape. Until next time, I’ll see you down a Cross Timbers Country road and God Bless America!