Texas sage is underutilized as a landscape plant

Q: I noticed several shrubs at the entrance to Carbide Park in La Marque that were loaded with lavender flowers last week.

What is the name of the shrub and would you recommend it for local landscapes?

A: I received several calls about this shrub commonly known as Texas Sage. The scientific name is Leucophyllum frutescens.

It also is known by several other common names including Purple Sage, Texas Ranger, Silverleaf, White Sage and Cenizo.

It sometimes is called “Barometer Bush” because flowering is triggered by high humidity or high soil moisture after a heavy rain.

Just a few days after the most recent rainfall in the area, Texas Sage lived up to its reputation — all four shrubs at the entrance to Carbide Park were a blaze of lavender-colored flowers.

Though underutilized as a landscape plant in our area, Texas Sage is one of our most outstanding native plants.

Texas sage is a native of the Chihuahuan desert in Texas, New Mexico and northern Mexico. It is a medium-sized shrub with a compact form and delicate silvery to gray-green leaves.

To thrive in the landscape, Texas Sage must have full sun and very well-drained soil.

Overwatering or poor drainage will quickly kill it, and shade will promote leggy growth and less flowering.

It is a low maintenance plant that will care for itself after it becomes established.

Texas Sage is one tough plant and it gets my 2011 Energizer Bunny Landscape Plant Award for its exceptional performance during our exceptionally dry spring season.

It can face droughts, freezes, high winds, salt spray and blazing heat and keep right on performing beautifully.

Q: Is it true that some caterpillars can sting you like a wasp?

If so, how do we know which ones to be on the lookout for?

A: Although many caterpillars have a threatening appearance, very few species are actually harmful to the touch.

The stinging caterpillars have stiff poisonous hairs or spines on their bodies that are connected to poison glands.

When a person comes into contact with the spines, they break and venom is released.

Reaction to this venom varies from mild to severe. Small children can have severe reactions.

Injury from these caterpillars is most common among children playing in yards and under low hanging tree limbs.

Fortunately, these caterpillars are around only in late summer and fall.

There are several to be on the look out for. The puss or asp caterpillar is the worst. The caterpillars grow to about 1 inch long and are furry in appearance, being completely covered by thick tan to grayish-white hairs.

You cannot see the eyes or the legs. This caterpillar is often abundant and may infest shade trees and shrubbery around homes, schools and in parks.

The saddleback caterpillar also is common. This one is very colorful and striking in appearance.

It grows to about 1 inch long and is pale green in color but with a purple or brown center that resembles a saddle on its back. Its sting is less severe than the puss or asp caterpillar.

The Io moth caterpillar also is around. Food plants range from grasses and herbs to foliage of some hardwood trees including apple, elm, hackberry, maple, oak, sycamore and willow. It grows to about 2 inches in length and pale green in color.

The Io moth caterpillar has a very striking set of stinging spines that would seem to say “Touch me and you’ll really regret it.” However, the sting is relatively mild.

Q: The entire trunk of my oak tree is covered with a silken, spider-like web. What’s wrong? What can I do to treat this?

A: The silken web is produced by barklice; and yes, they are insects but don’t get out the nuclear bug killer arsenal because barklice are very beneficial.

The trunk of a heavily webbed tree can sometimes look like it has a silk stocking on it. Sometimes only patches of the silken webs will be noticed.

This seems to be the season for barklice, judging from the numerous calls to the extension office regarding this creature.

Even though they are called barklice, they are not true lice and they are not parasites. They do not harm trees and, in fact, are quite beneficial.

Barklice occur on the trunks and primary branches of a number of trees where they feed on lichens and fungi growing on the bark.

While barklice occur most frequently on oak trees, they can occur on most types of landscape trees except for pines and other conifers.

If you have near 20/20 vision and look very closely at the webbing, you may be able to locate clusters of very small, brown-colored, soft-bodied insects.

Even though the webs may become unsightly, try to avoid using insecticides — barklice are of benefit to the tree. The silken webs will disappear by late summer or early fall.

Dr. William Johnson is a horticulturist with the Galveston County Office of Texas AgriLife Extension Service, The Texas A&M System. Visit his Website at http://aggie-horticulture.tamu.edu/galveston.