South Texas ChapterTo the South Texas Chapter Master Naturalist Website!
The Texas Master Naturalist program develops local teams of “master volunteers” to provide educational and outreach services aimed at the better management of natural resources and natural areas within their communities. The Texas Master Naturalist program is a partnership between the Agrilife Extension and Texas Parks & Wildlife.
On this site you will find information on volunteering, advanced training, where we meet, our calendar of events, how to become a Texas Master Naturalist, and more!
Check out the Texas Master Naturalist 20th Anniversary Project!
The Texas Master Naturalist Program will be celebrating its 20th Anniversary in 2018. As we approach that milestone, we will be collecting stories and the history of our program through a number of different media types. We will use this page to share information requests with our TMN Chapters. More information and resources will be posted as they are developed.
Critter of the Month: Acacia Girdling Beetle
Acacia Girdling Beetle, Oncideres pustulata, is often observed by those of us conducting classes at the Nueces Delta Preserve, Welder and to alesser extent the Botanical Gardens. It is uniquely adapted to have its life cycle as part of the acacia (in this case Huische) and to a lesser extent Tejuape. While we only see them at a certain time, the evidence of them is observable year round. As one walks a trail of Huische in South Texas, it appears that someone came through and pruned the trail with a chain saw. However, this is usually not the case. In fact, the girdling beetle is responsible. There are many types of girdling beetles which are a long-horn beetle. During late Summer and early Fall, Girdling Beatles emerge, while mating is reserved for late Winter/Spring. The females bite holes in branches in order to deposit eggs into the distal end of the girdled branch. Observation of any fallen branch reveals tiny pin-head size holes all along the branch on the ground. There may be one to many females on the branch doing their business. The male is busy cutting a 1/2 centimeter ring around the living Huische branch. It gnaws through the bark through the xylem and phloem effectively killing the branch. Gravity, wind, or both ultimately topple the branch to the ground. It is the dead Huische that is now the home for the maturing larvae of the Girdling Beetle to eat within the branch until maturity. On calm, quiet days the gnawing sound of the adult male can be heard girdling the branch and often as one walks the trail in the Fall, branches will fall within earshot. It is this time of year that one can readily observe the male and female busy working. Maybe we will observe some on Training day at the Delta. The larvae within the bark becomes a favorite source of food for the Ladder-backed Woodpecker which will work the piles of fallen branches. As branches deteriorate, other critters fill the space between bark and pith. Ants, other beetles, spiders are commonly found. Collectively these critters are composting the tree.