By Jake Landers
Published November 2012
Two woody plants of our area are seldom noticed by ranchers because they are rare on our rangeland, and because they have little impact on livestock or wildlife anyway. But, maybe they are beginning to get a little attention from our city cousins concerned about water conservation and landscaping with adapted species.
I’m referring to Kidneywood and Mexican Elderberry—large bushes or small trees that grow in a few scattered locations in the southern half of Texas and Mexico. Kidneywood prefers rocky calcareous outcrops and Mexican elderberry stays on the edge of streams or river banks where it can benefit from the extra water. Both species have received attention from the landscaping trade because of their drought resistance and ability to grow when water is available into small attractive trees. Both become small trees with pruning and good growing conditions. If planted north of halfway in Texas, they may suffer some frost injury.
The wood of Kidneywood has the unique property of producing blue phosphorescence when placed in water, perhaps the reason it was once thought the plant has medicinal value. Its leaves when crushed smell like tangerine peels, another reason that it may have attracted medical attention. Its scientific name is Eysenhardtia texana. Another common name is Vara dulce. With abundant summer moisture it blooms with a glut of tiny white to yellow-white, sweet smelling flowers that are attractive to many butterflies and bees. Pods are one seeded and as small as an inch of scoring pencil for bridge or golf.
Kidneywood can be browsed by goats and deer to the point of gnarled stubby branches. I have found no reference as to the origin of “kidney” in its common name; perhaps its leaves smell strong enough to be of some benefit as a placebo in our numerous complaints of kidney problems in old age.
Mexican elderberry has the ability to sprout from a piece of freshly cut wood, a very unique property among woody plants that is beneficial in landscape propagation. A very large pith is common in all the Elderberry species, and many times I have used it to embed biological specimens, slicing off thin sections for microscopic examination. Its scientific name is Sambucus mexicana with other common names of Tapiro, Sauco, and Azumiatl. Flat-topped clusters of white flowers become, at the end of spring, clusters of purple berries which have the reputation, at least, of producing some Elderberry wine.
I don’t know of Mexican elderberry’s value as browse. Its local elderberry cousin is not browsed by deer while nearby Pecan sprouts are kept bare of leaves as high as they can reach. The pith is poisonous, as we were told in botany classes, and I presume that other parts of the plant are also suspect. The berries on the other hand are safe enough to eat or to use in making wine or jelly. Chances are there is some toxicity in the leafy parts to reduce browsing, but the seeds are probably transported by birds and other wildlife eating the berries, and it would be self defeating to do harm to the seed carrier.
Reading The Landscape
Can you identify this plant that is common in roadsides and pasture this month in central Texas where moderate amounts of rainfall have been received in late summer? Is it of value to the rancher? Would you consider it detrimental or beneficial for the land? —JL
|See below for Jake's answer|
Jake’s summary: The plant is Dove weed, also called Croton, which comes up only from seed when summer moisture is adequate and there is little competition from dense grass cover. The seeds are relished by Dove and Quail and other seed-eating birds. A strong croton oil odor is produced when the leaves are crushed making it completely unpalatable for most grazing animals. A very dense stand may suppress the recovery of desirable range grasses. The scientific name is Croton monanthogynus. —JL