The Plant Press

From The Plant Press, Vol. 26, No. 1, January 2023.

Amigos de las Gramíneas en México

By Paul M. Peterson and Konstantin Romaschenko

Paul Peterson, Research Botanist and Curator, has been collaborating with botanists in México for more than 37 years on taxonomic, biogeographic, and evolutionary studies of the grasses. This past fall, from 15 October to 16 November 2022, Peterson and Konstantin (Kostya) Romaschenko, Research Associate, traveled to Central México to collect specimens for numerous ongoing projects principally involving Dr. Yolanda Herrera Arrieta at Instituto Politécnico Nacional, CIIDIR Unidad Durango-COFAA in Durango and Dr. Jesus Valdés Reyna at the Universidad Autónoma Agraria Antonio Narro in Saltillo.

The flora of México is extremely diverse, and the country ranks fourth in the world with more than 30,000 different species of flowering plants, compared to only 18,000 in the USA and 12,000 in all of Europe. The Poaceae or Gramineae are also diverse in México with more than 1,300 species. Peterson has traveled and collected more than 13,500 numbers in México on 28 expeditions, beginning in 1983 and 1984 with Robert F. Thorne and Carol Annable to the Sierra Juarez and Sierra de San Pedro Mártir in Baja California, and then throughout México in 1985 and 1986 to gather material of the annual species of Muhlenbergia in the tribe Cynodonteae for his PhD studies. If you want to work on grasses Muhlenbergia is a good choice because it is the most speciose genus in México with 130 species. The National Museum of Natural History’s previous Curator of grasses, Thomas Soderstrom worked on the tall perennial species of Muhlenbergia (subg. Trichochloa) for his PhD studies.

Peterson and Romaschenko collected a total of 311 numbers in eight estados (states) beginning in Zacatecas (with Y. Herrera Arrieta), Durango, and Sinaloa; then heading north to Saltillo to collect in Coahuila (with J. Valdés Reyna and Jaime Flores Gaoña), Nuevo León, and Tamaulipas; and finally returning to Hidalgo and Querétaro in Central México. The principal objectives of this trip were to collect material in silica for DNA sequence studies to investigate the phylogeny of the tribe Stipeae, especially Pseudoeriocoma and Eriocoma, in collaboration with Valdés Reyna, and Muhlenbergia for revisions in Central America and México, both in collaboration with Herrera Arrieta. Even though the Stipeae are cool-season C₃ grasses and the Cynodonteae are warm-season C₄ grasses, both tribes include species that are well adapted to the xeric conditions that predominate in most habitats throughout México. Hence, Romaschenko and Peterson have ample opportunities to gather material they specialize in.

While in Nuevo León after collecting in Coahuila for three days with Valdés Reyna, the team stopped at Rancho Aguililla near Galeana to visit George Sebastian Hinton who lives and maintains a private herbarium with specimens collected by him, his father (James or Jaime), and his grandfather (George Boole Hinton, 1882‒1943). The three generations of Hinton’s have contributed to the description of six new genera and 621 new species found in 13 Mexican states (see Hinton et al. 2019, https://doi.org/10.17129/botsci.2210). George S. began collecting on his own in 1984 and has accompanied Peterson and Romaschenko in the field numerous times. On this trip the team made a short visit to inquire about collecting in Tamaulipas. George S. telephoned a colleague who indicated it would probably be safe to be out and about during daylight hours in the western portion near the border of Nuevo León. In 1999, Peterson and Valdés Reyna described a new speciesendemic to Nuevo León, Muhlenbergia jaime-hintonii, incorrectly attributing the epithet to James rather than George S., the first collector.

Several areas of México are not safe to travel and camp, including Tamaulipas, but the team was determined to gather material of Pseudoericoma editorum as close to the type locality (W.F. von Karwinsky 1009c collected in La Noria del Viejo et la Miquihuana, Tamaulipas in 1841 or 1842) as possible since they detected two putative species of P. editorum appearing in separate clades in their molecular phylogeny. So, the pair made a one-day dash to Miquihuana entering Tamaulipas on a small road from the town of Doctor Arroyo in Nuevo León that was headed towards Ciudad Victoria where most of the recent terrorist activity has occurred. Once in the tiny Puebla of Miquihuana they ate lunch at a small restaurant and struck up a conversation with some locals and inquired if they might know where Noria del Viejo (old man’s well) was located. The locals suggested looking just north of the town where an old rancho once existed and perhaps in 1841 it was the only place where water could be obtained. The team then drove along the northeast perimeter of Miquihuana, and this road eventually led to a small path up a steep slope composed of calcareous rocks where they could see in the distance a monumento del Cristo (monument of Christ). They walked up the path about 600 meters and just below the monument they encountered specimens of P. editorum growing among the protection of Agave, Opuntia, and Vachellia (newer name for Acacia). This grass is highly selected for by livestock.

Having concluded their forays in northeastern México Romaschenko and Peterson headed south to Hidalgo and Querétaro. In Hidalgo they returned to Rancho Viejo where, while collecting in 2018, 2019, and 2022, the duo camped under a large avocado tree near a small farm managed by Arturo, their amigo. Above Arturo’s casa along the ridge and into a cloud the group found the pastures primarily composed of European and African grasses, such as Cenchrus clandestinus, no doubt maintained by heavy grazing of livestock.

They returned to a Juniperus‒Quercus woodland near La Nueva Griega, Querétaro, and camped (same location in 2016, 2018, and 2019) on land owned by Marcos Laredo, another amigo, who enthusiastically greeted them and immediately returned with tacos prepared by his wife for their cena (dinner). He had many stories to share with the group including an unusual story of his problems managing his cattle—someone had killed one of his cows with an arrow but did not remove the dead animal or any of the meat. Peterson recalls camping at this location in Querétaro three times over the past six years and having gathered at this site a diverse array of indigenous grasses. In 2022 there was only a few of these grasses left and now replaced with many introduced grasses, again indicating a loss of habitat due, in part, from intensive grazing and soil compaction from hooved animals.

Duplicates from their collections will be deposited in the CIIDIR Herbarium in Durango, and Romaschenko and Peterson will cite and include distribution and habitat information in their upcoming phylogenies and revisions of Eriocoma, Muhlenbergia, and Pseudoeriocoma.