Plant Conservation Biology

Distribution, Population Size, and Reproductive Status of Chamaesyce jejuna in Nolan, Mitchell, Pecos, and Terrell counties of Texas

This project is starting its second year of research in spring 2014 and is funded by a Horned Lizard License Plate Grant (HLLP), which is part of the Wildlife Diversity Program of Texas Parks &Wildlife Department (TPWD). Chamaesyce jejuna, commonly called Dwarf Sandmat, is a rare, endemic plant restricted to caliche uplands and limestone hills of the Great Plains and Chihuahuan Desert ecoregions of Texas.  This plant species is at risk for extirpation from its known range. In 2013 TPWD gave an HLLP Grant to conduct fieldwork to determine the distribution and status of known but not systematically surveyed populations in Nolan and Mitchell Counties and to attempt to relocate a historic population in Pecos County. Results of fieldwork during spring and summer of 2013 verified the persistence of the Nolan and Mitchell County populations and relocated the historic population in Pecos County. The existence of this population had not been confirmed since 1960.

Dwarf Sandmat
Dwarf Sandmat
Dwarf Sandmat distribution

Dwarf Sandmat (Chamaesyce jejuna)

Chamaesyce jejuna inflorescence

Distribution of Chamaesyce jenuna.
Counties in yellow indicate Texas counties where populations of Chamaesyce jejuna have been known to occur. The southernmost set of counties are historic populations and have not been verified in recent decades.

Spring 2014 Field Research:

My Hardin-Simmons University May Term course, BIOL 4411 Natural History of the Southwest, will be conducting an extensive field survey on the (former) historic population in Pecos County. In addition, we will conduct an extensive field survey to search for new populations in Terrell County based on verified herbarium record data. We will also conduct follow up surveys on known Nolan and Mitchell County populations.

Horned Lizard Licence Plate

Ecology Education and Pedagogy

I have been collaborating for the past year with colleagues at Texas A&M University and Penn State University in the area of inquiry-based learning. It may be especially beneficial in the context of ecological education given the field-observational and experimental orientations of the discipline. Field-based inquiries are often not feasible in large introductory ecology courses or classes with limited access to suitable field sites. Virtual learning environments can help overcome this difficulty. Virtual inquiries based on simulations can be attractive to today’s students who are familiar with electronic gaming. A virtual learning environment in Second Life, Virtual Ecological Inquiry (VEI), based on the ecology of Wolong Nature Reserve, has been developed and implemented in a large introductory ecology course at Texas A&M since 2011. In Fall 2013, the VEI inquiry project was implemented in four institutions of different types (a research university, a comprehensive university, a liberal arts college (Hardin-Simmons), and a Hispanic Serving Institution) to test the transferability of the VEI and explore institutional contexts and other factors affecting its implementation and effectiveness. A post-project survey was conducted for student self-assessment of their learning and feedback for the projects. My colleagues and I will be presenting a contributed poster based on our data at the 2014 Ecological Society of America annual meeting in Sacramento, CA in August. Below are some screenshots from the Second Life VEI application.

Ecologoy lobby
Setting a transect
Observing a transect

Second Life allows for real-time interaction and information distribution for a better learning experience.

Students will be able to model real life situations such as setting transect lines within the Second Life learning environment.

Second Life provides a distribution method to quickly analyze digital transect lines and gather information for experimentation.


Tropical Ecology in Costa Rica

I taught a tropical ecology course in Costa Rica during the May Term 2013 semester. Students who participated in this course will take part in field studies of primary succession in Arenal Volcano National Park. I plan to offer this course again for May Term 2015. Interested HSU students should contact me for more information. The first image below shows primary or virgin rainforest. The second image below shows the author and Arenal Volcano in the background.

Costa Rican rainforest
Arenal Volcano

Author standing in front of Arenal Volcano in Costa Rica

Primary Rainforest in Costa Rica

Waterfall in primary rainforest, Costa Rica


Recent Publications

Hammer, R.LHatch, S.L.,  Pepper, A.E., and Manhart, J.R. 2012. Concordance between Molecular and Morphological Evidence of Hybridization in the Dichanthelium acuminatum (Poaceae: Paniceae) Subspecies Complex. Description: full accessSouthwestern Naturalist, 57, 133-137.