I really believe the soapweed is a native plant in this area. at least I have never found any thing different. Folk lore sometimes says other plant were brought here by the trailed in longhorns from texas, but they were on the trail for about 3 months so most any seeds would have passed through their system long before they reached here.
Here is my comments on the soapweed for what it is worth:
Yucca or small soapweed:
this plant most commonly called soapweed in this area, is a perennial, evergreen, native,palm-like plant. It is frequently found on dry soil, in the Sandhills and on rocky and barren or exposed hillsides.
This course large plant has long, stiff waxy leaves that are smooth. A few thread-like marginal hairs may be found on the leaf margins. The leaves arise from the base of this plant and may be as long as two feet, or in a few instances longer, but are usually no wider then 1/2 inch.
Long stout flowering stalks grow from the center of this plant. In June, large greenish white flowers appear on 1 or 2 sides of this stalk. The flowers are bell shaped, are suspended from a short stem, droop, or hang in a downward position and do not appear to entirely open. The base of the blossom may br tinged, or lined with purple or red. This plant is so distinctive that it can be confused with no other. A yucca plant only produces blossoms every other year, however secondary plants, produced from a single parent plant may produce blossoms on alternate years.
It has an extensive root system roots are long and thick. They may be two or more inches in diameter. The roots are fibrous and porous.. Pieces of exposed root of soapweed are oftern found in sandhill blowouts. If you examine these roots you will get some idea of the makeup of this plants roots and the extent of it's root system. This plant is something of a succulent, and stores moisture in it's roots and the lower portion og it's leaves.
Reproduction of the yucca is by underground roots and by seed. It is common ti find several second generation plants connected to a common root system. all literature on the yucca plant makes mention on it's dependence of the pronuba moth for seed production. This is a small, silvery, night-flying moth. It gathers pollen and places in on the stigma, but also deposits eggs in the developing capsule. The larvae of this moth feed on some of the developing seeds. It is interesting to speculate on the special relationship between this moth and the yucca, as neither would survive without the other. People who have studied this special phenomenon have concluded that there is even a specific species of this moth for specific species of the yucca.
The seed calsule of the yucca is large, about 2 inches in diameter and about 3 inches long. The seed capsule is discribed as being 6 sided and has 3 cells. They contain many black flat seeds that are somewhat winged.
The roots of this plant were cut in small pieces, mashed and rubbed together in water. This produces a soaplike lather which leaves the skin soft and pliable. This was used by both the Indian and thhhhe white man. The American Indians used this soap to wash their hair as it is a vermin killer. A comercial soap (Aniole or Ammole) was made from yucca.Some Indian groups mixed soapweed with duck oil and used it to treat baldness. It's effectivness like that of many herbal remedies is questionable.
I have been told, after I wrote this, that some Native America tribes in the southwest used yucca in the bath water for the first bath of babies. There might have been some cerimonial significance for this as some still do that today.
While of limited value as a forage plant, few other native plants had as many uses as the yucca. The buds of the flower were eaten either raw or cooked. The petals can be used in salads, the stems of the young flower stalk could be pealed and roastd or boiled. The seed pods can be picked while green and roasted, they are said to taste something like sweet potatoes, and were sometimes baked in the ashes of a fire. The pulp of the fruit was boiled into a paste, then rolled into sheets and allowed to dry and used as a stoed food. The pulp of nearly ripened fruits were sliced and used to make a mock apple pie. The leaves were macerated and the strings and fibers used for thread, or were soaked in water and used to make cord. During World War II fibers from the yucca as a substute for jute for making rope, twine, and bagging. The leaves were also used by the early people for weaving baskets, sandals etc. The roots and dried stem were used at the hearth as (punk) for kindling fires. Dried leaves were also used as tinder. I have fought prairie fires on rangeland badly infested with soapweed. When fire reaches a soapweed plant with it's accumulation of dried leaves it will literally explode. This is much like pouring kerosene on the fire. The base of the plant and exposed roots will remain burnign and glow as coals for a long period of time.
Soapweed ha little value as a grazing plant. Cattle will eat the succulent young leavesto a small extent. Large wildlife like elk, may use it to some extent for forage. Cattle and horse relish the soapweed blossoms, and seed pods. Once accustomed to eating them, they will forage the entire pasture and eat off all of the blossoms. They eat the flower stalk to some extent. In the southwest the leaves and stem of the yucca were choped and fed along with cottonseed cake as an emergency feed.
There are about 30 species of yucca, mostly in the Southwest and in Mexico. The soap tree yucca has a trunk that will grow several feet in height, the leavs growing at it's top. When I was in the service, I had the occasion to be in the area where the bomb test were held. I rcall driving over a "yucca log". It was soft and porous and shatterd like a rotten log.
Othe common names for yucca are soapweed, Spanish Bayonet, Adams needle, Palnilla Bear Grass, Grass Cactus, or cowboy cactus. someone jokingly said that because of ot's sharp and pointed leaves it helped the cowboy get back up after being bucked off his horse.
The scientific name for the species that grows here is Yucca glauca. Yucca is said to be a Haitian name for s tropical food plant. A seventeenth botanist, John Gerard, is said to have applied the name to this plant. Glauca is said to be from the Greek and to mean grayish or blueish green. Yucca or soapweed belongs to the lilly family.