Arboretum Newsletter Number 9 (April 10, 2015)
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Deergrass: A Native Bunchgrass Planted At Palomar College
by W.P. Armstrong
Reprinted from Arboretum Newsletter Number 9 (April 10, 2015)
One of the most conspicuous plants of mountain meadows in San Diego County is deergrass (Muhlenbergia rigens), a tall, perennial bunchgrass. It forms dense clumps up to four feet tall in Doane Valley, Palomar Mountain, and across meadows of the Cuyamaca and Laguna Mountains and Pine Valley. It also grows in moist canyons on the coastal and desert sides of the mountains, including Borrego Palm Canyon, Gopher Canyon and tributaries of the San Dieguito River. There are 17 additional species of Muhlenbergia native to California, generally smaller grasses often referred to as “muhlys.” They belong to the large grass tribe Agrostidae, along with bentgrass (Agrostis), three-awn (Aristida), needlegrass (Stipa), and reedgrass (Calamagrostis). Recent DNA analyses place Muhlenbergia in the subfamily (DNA clade) Chloridoideae, tribe Eragrostidae.

Deergrass (Muhlenbergia rigens) in a meadow at Cuyamaca State Park.

Grounds supervisor and horticulturist Tony Rangel planted deergrass on the campus of Palomar College at the west end of the TLC Building (Teaching Learning Center). Deergrass is drought tolerant, has few insect pests, and is relatively low maintenance. The following comment is from the Dave’s Garden on-line page: “Fast growing California bunch grass. It gets about 2 feet tall and the plumes are another two feet above that. It is quite spectacular. Can be grown as a specimen or multiples. Very low maintenance, only need to cut it back once a year before the new growth starts. Does not seem to be as demanding with respect to drainage as many other natives. Water efficient. This is a very good grass.”

Deergrass planted at west end of the TLC Building (Teaching Learning Center)

Deergrasss: An Important Plant In Cahuilla Culture
Deergrass was very important in the lives of Cahuilla people because of its use as foundation bundles in baskets. It was also used for the foundation in Kumeyaay baskets. The following information about Cahuilla basketry is from Dr. Deborah Dozier of the Palomar College American Indian Studies Department: The patterned surfaces are all made by wrapping a foundation bundle of cleaned and sized deergrass stems in paper thin strips of basket sumac (Rhus trilobata) and more typically basket rush (Juncus textilis). The sumac is left untreated and is valued for its pure white color. Juncus is valued for the distal end that is buried in the soil and turns a mahogany red, as well as the golden tan color that most of the rush takes when properly dried. Sometimes the Juncus is dyed black using the leaves of elderberry (Sambucus mexicana) mixed with emptied hulls of acorns, mostly black oak (Quercus kelloggii). When the basket is finished, no trace of the deergrass foundation is visible.

Cahuilla baskets and expert basketmaker Dolores Patencio circa 1910-1920. She is working with a bundle of deergrass stems (hanging down to her right).

To create a basket 14 inches in diameter and 4 inches deep takes about 1,500 stalks (culms) of deergrass. The pattern of the stitching in a top-notch basket is remarkable in that it expresses the same Fibonacci patterns as pineapples, pine cones, and other arrangements of rotational geometry. It is amazing that these women did this at 40+ stitches per inch without any pattern to follow. For more information see Temalpakh: Cahuilla Indian Knowledge and Usage of Plants by Lowell John Bean and Katherine Siva Saubel (1972).

A Kumeyaay basket. Durova (2007) San Diego Museum of Man (Wikimedia Commons).

General structure of a coiled basket. Bundles of flowering stems (culms) of deergrass (Muhlenbergia rigens) were commonly used by the Cahuilla, Kumeyaay and other tribes for the foundation (primary coils) of the basket, around which the secondary coils were tightly wrapped. Basketbush (Rhus trilobata) was commonly used for the secondary coils, with intricate designs made from brown coils of rush culms (including Juncus acutus, J. effusus, J. lesueurii and J. textilis). Sometimes the rush culms were dyed to produce various color patterns. Other plants were also used for basketry in the American southwest, including willow (Salix), beargrass (Nolina microcarpa), yucca (Yucca elata) and devil's claws Proboscidea parviflora ssp. parviflora var. hohokamiana.

A Native American basket from the Kumeyaay of San Diego County, California. The secondary coils are made from the rush stems (Juncus). The primary coils are probably made from culms of deergrass (Muhlenbergia rigens).

  Devil's Claws & Papago Basketry  

Did Dinosaurs Dine On Grasses?
Dioramas in museums have long depicted large sauropod dinosaurs grazing on conifers, cycads and ferns in landscapes without grasses. I was always under the impression that grasses came later in the evolution of flowering plants. Although flowering plants date back about 130 million years ago, the earliest unequivocal grass pollen and macrofossils date back about 56 million years, well after the demise of dinosaurs at the end of the Cretaceous Period. The Paleocene-Eocene Boundary (formerly called K-T Boundary) when a giant asteroid collided with Earth is usually placed at about 65 million years ago. In the November 18 issue of Science (2005), Caroline Strömberg of the Swedish Museum of Natural History and her colleagues from India report phytoliths in the fossilized dung of sauropods that lived in central India about 65 to 71 million years ago ("Dinosaur Coprolites and the Early Evolution of Grasses and Grazers." Science 18: 1177-1180).

The best explanation (scientific theory) for the mass extinction of non-avian dinosaurs is an enormous 10 km (6 mile) diameter asteroid that collided with the earth about 65 (65.5) million years ago causing a global dust cloud that blotted out the sun for many months. Estimates as high as 85 percent of all species disappeared from the face of the earth at this time. This catastrophic event forever changed the direction of the evolution of life on earth.

  K-T Boundary--Giant Asteroid Hit Earth: Mass Extinction Of Dinosaurs  

Phytoliths are microscopic silica bodies found inside the cells of stems and leaves of grasses and other plants. Depending on the species of plant, they range from 5 to 100 micrometers in length. Because they are made of a crystalline form of silica called opal, they are very durable and retain their characteristic shapes over millions of years. Different genera of grasses have phytoliths with unique shapes, including square, rectangular, oblong, bilobed, wavy with undulate margins, butterfly and dumb-bell shaped. Grasses belonging to the subfamily Panicoideae typically have phytoliths that are dumb-bell shaped. This includes the genera Digitaria, Panicum, and Pennisetum. Phytoliths of North American Muhlenbergia species show a variety of shapes, including saddles, bilobates and dumb-bells. Like microscopic pollen grains and diatoms, the phytoliths remain perfectly preserved in spaces between soil particles. Phytoliths have recently been discovered in dinosaur coprolites, evidence that these enormous prehistoric herbivores fed on grasses.

Dinosaur “poop” (coprolite) and magnified view of minute silica phytoliths inside a leaf of crabgrass (Digitaria sanguinalis). A row of 9 phytoliths is compared in size with a grain of table salt!

Phytoliths have been an important factor in the evolution of grazing herbivores that feed exclusively on grasses. During the lifetime of an animal that consumes large quantities of grasses, its molars gradually wear down. These animals have evolved high-crowned teeth that in some cases continue to grow from the base as the crowns are worn away.

The grass family contains more than 10,000 species and is the 5th largest family of plants. It has been estimated to comprise 20 percent of the vegetation cover of all the Earth’s continents. It is the major food source for all primary consumers and the most economically important family (wheat, rice, corn, millet, sorghum, sugar cane, etc.). Dinosaurs definitely fed on grasses, at least later in the dinosaur era. Grasses are also used extensively in landscaping, particularly lawns and decorative bamboos. In the case of our native deergrass, it makes a stunning landscape plant that reminds one of the beautiful meadows of our nearby mountains and canyons. For additional information about dinosaurs and grasses, see following page on Wayne’s Word:

  Dinosaurs Dined On Grasses In India