Skip to Main Content
Have library access? Log in through your library
Field Guide to Grasses of California

Field Guide to Grasses of California

James P. Smith
Illustrated by Kathy Simpson
Copyright Date: 2014
Edition: 1
Pages: 448
  • Cite this Item
  • Book Info
    Field Guide to Grasses of California
    Book Description:

    Grasses and grasslands are of increasing interest to conservationists, biologists, and gardeners. There are more than 300 species of native California grasses and they are found in almost every climate-from cool, wet forests to hot, dry deserts. Native grasses are also important to land restoration as they improve soil quality, increase water infiltration, and recycle nutrients. Their deep roots can tap soil water, which allows them to stay green year-round and to act as fire buffers around residences. Native grasses also provide vital habitat for many species of insects, birds, reptiles, and mammals. Despite their importance, grasslands remain one of the most underprotected of California's vegetation types, and native grasslands have undergone the greatest percentage loss of any habitat type in the state. Grasses are also among the most difficult plants to identify. Organized alphabetically,Field Guide to Grasses of Californiacovers common native and naturalized grasses and, to help identify them, also features over 180 color illustrations.

    eISBN: 978-0-520-95843-2
    Subjects: Botany & Plant Sciences

Table of Contents

Export Selected Citations Export to NoodleTools Export to RefWorks Export to EasyBib Export a RIS file (For EndNote, ProCite, Reference Manager, Zotero, Mendeley...) Export a Text file (For BibTex)
  1. Front Matter
    (pp. i-vi)
  2. Table of Contents
    (pp. vii-viii)
    (pp. ix-x)

      (pp. 1-5)

      This book is about the most frequently encountered plants in California. For many of us, grasses are also the least known and perhaps the most intimidating component of our flora. My purpose in writing this book is to provide you with the background and tools that you need to identify the more common native and naturalized grasses and thereby to cast doubt on the notion that only a small group of experts who have spent many decades of study are able to tell one grass from another. This will take some time and effort on your part. Most worthwhile projects...

      (pp. 6-14)

      What Are Grasses?

      The word “grass” itself has a complex etymology. In the broad sense, it has been applied to small herbaceous plants in general, particularly those whose leaves and stems are eaten by wild or domesticated animals. It may trace back to the Indo-Iranian word “ghra,” which means “to grow,” and to the concepts of green and grain. In this sense, grasses are more or less nondescript greenery.

      Our focus is much narrower. All true grasses belong to a single family of flowering plants,Gramineae. I use the phrase “true grasses” because there are many plants that have “grass”...

      (pp. 15-22)

      Most of us refer to grasses by their common or vernacular names. They are often simple, easy to remember, descriptive, colorful, pleasing to the ear, and easy to pronounce. Given this impressive list of advantages, why not just use common names for grasses and be done with it? Here are some of the reasons:

      A grass may have more than one common name.Sorghum bicoloris variously named sorghum, sorgo, kafir, durra, milo, broom-corn, and chicken-corn.Stipa hymenoidesis called Indian rice grass, Indian millet, silk grass, and sand bunch grass.

      The same common name may be used for more...

      (pp. 23-26)

      There has never been any significant disagreement about the limits of the family itself. Grasses are grasses. However, there has been considerable controversy about the major groupings within the family—its subfamilies and tribes. These are formal categories in the taxonomic hierarchy. Their names are governed by the rules in theInternational Code. Subfamily names end in the suffix -oideae, as inBambusoideae. Tribe names end in the suffix -eae, as inPaniceae.

      The great British botanists Robert Brown in 1814 and George Bentham in 1881 both theorized that there were two great groups of grasses, one of them centered...


      (pp. 28-32)

      Most mature grass plants have a fibrous root system that is finely divided and lacks a clearly dominant root. This system is also termed adventitious, in that the primary root system is short-lived and is quickly replaced by roots that arise from plant parts other than the primary root and its branches. Typically these roots are found at the base of the stems.

      Prop roots are aerial roots that arise from stem nodes, penetrate the soil, and serve to support the grass plant. Maize often produces very conspicuous prop roots. The extent and penetration of the grass root system is...

      (pp. 33-34)

      Most of us have never seen grass flowers; in fact, we are perhaps not even aware that grasses are flowering plants. This is understandable. Grass flowers are small and hidden away from easy view by a system of reduced leaves (bracts). This is another way of saying that grasses do not strike most people as being terribly pretty. But, come closer!

      The brightly colored sepals and petals that make the somewhat distantly related lilies and orchids so attractive have been lost through the gradual processes of evolutionary reduction. All that remains for most grasses are two, or rarely three, almost...

      (pp. 35-40)

      The word itself literally means a small spike; that is an accurate description. A spikelet consists of a central stalk, one or more grass flowers, the minute side branches to which they are attached, and a series of bracts that enclose them. Some spikelets, especially those containing a single flower, may be quite small. Others are a few centimeters long and easily seen without magnification. The spikelet, although characteristic ofGramineae,is not its exclusive property; sedges also have spikelets. Because their spikelets are superficially similar, it is easy to confuse the two families. Refer back to Table 3 for...

    • INFLORESCENCES The Arrangement of Spikelets
      (pp. 41-44)

      A grass stem, whether it is the main stem or a lateral branch, may bear one to several hundred spikelets. This flowering portion of the grass plant is its inflorescence. A stem may bear only one inflorescence or it may have several of them. If it emerges from the uppermost sheath of a primary stem, it is a terminal inflorescence. If it arises from the node of a lower sheath, it is an axillary or lateral inflorescence.

      At first, it may be difficult to determine just how much of what you are seeing is a single inflorescence. A good rule...


    • CALIFORNIA GRASS FLORA A Numerical Overview
      (pp. 46-53)

      California’s grasses are mostly native perennials:

      There are 8 subfamilies, 18 tribes, 117 genera, 547 species, and 603 taxa (species, subspecies, and varieties) of grasses in California.

      39% of the grasses known from the conterminous U.S.A. occur in California.

      Our grass flora is larger than that of Canada (434 taxa) and any other state, except Texas (681).

      181 taxa (30.0%) are annuals

      422 taxa (70.0%) are perennials

      328 taxa (54.4%) are native

      275 taxa (45.6%) are naturalized grasses native to other states or countries

      54 taxa (8.9%) are endemic (found only in California)

      274 taxa (45.4%) are native, but also...

      (pp. 54-83)

      Grasses are everywhere in California! They are commonly encountered as natives in almost every habitat and as introductions and weeds where we live, travel, and grow our crops. They reach their greatest expression in California’s grasslands—areas where grasses and grass-like plants (mostly sedges) are the dominant life form. We do not say they are dominant because of their diversity: typically only three or four grass species are common and collectively they account for only about 20 percent of the flora at any particular site. Most of the plants in a grassland area are broad-leaved herbs. Grasses are dominant by...

      (pp. 84-88)

      One of the defining features of the California flora is its high number of endemics. For a plant to be considered endemic, it must be native to a region and confined to it. The size of the area or some other feature that describes an area becomes the defining criterion. A grass may be endemic to North America, or to California, or to the San Francisco Bay Area, or to serpentine soils or to coastal dunes. There are 348 grasses endemic to the conterminous United States; 92 of them occur in only one state (Smith 2010b). Of those, 54 occur...

      (pp. 89-91)

      Some grasses have been declared rare, endangered, or threatened by virtue of official action taken by the United States Fish and Wildlife Service (USFWS) or by the California Department of Fish and Game (CDFG), the federal and state entities legally empowered to make such declarations. The California Native Plant Society has also been monitoring the state’s rare and endangered plants for several decades and publishes an inventory of its findings, now in its eighth edition. Although its rating scheme has no independent legal standing, it is seen as scientifically authoritative.

      For federally listed plants, FE = federally listed as endangered;...

      (pp. 92-101)

      Weeds are of great economic importance, but mostly in a negative sense. They cost the American farmer several billion dollars each year by reducing both the quantity and quality of our crops. Their damage causes a loss as large as insect injury and disease combined. Another aspect of weeds is their intimate association with our own species. Many of them are essentially our wards and they would not have their present day distribution without our encouragement. As the noted American botanist Edgar Anderson once observed, “. . . the history of weeds is the history of man.”

      There are many...

      (pp. 102-108)

      Because the grass family is the source of so many important food plants, it may come as a surprise to learn that it is also the home of a number of poisonous plants—those that can disrupt the normal state of health of the victim. Symptoms range from relatively mild skin irritations to death. In other words, toxic or poisonous plants are not just those that kill the victim. The victims of grass toxicity can be wild and domesticated animals, humans, and even other plants. Mechanisms of grass poisoning include plant parts (especially awns and sharp-pointed calluses) that cause mechanical...

      (pp. 109-114)

      “Ethnobotany” may be defined as the study of the interactions of people and plants, especially the use of plants by people indigenous to a particular area. The purpose of this section is to catalogue the grasses that were used by Native Americans, the part of the plant used, and for what purpose from the time they migrated into what we now call California about 12,000 to 15,000 years ago. These people built their villages, worked, and camped in the grasslands. It was there and in adjacent woodlands that Native Americans gathered seeds, fruits, and bulbs; domesticated plants and animals; and...


    • [Introduction]
      (pp. 115-120)

      The principal reason for plant collecting is to provide permanent, representative specimens for identification, documentation, and further study. Many of these specimens will eventually become housed in an herbarium, a permanent collection of pressed and dried plant specimens. Here they will be examined by botanists and others interested in such matters as identification, distribution, blooming and fruiting times, general morphological features, anatomical details, chemical constituents, and even DNA analysis. Herbarium specimens are frequently loaned to experts doing monographic work and duplicates are often exchanged among herbaria.

      The goal is to collect and prepare a specimen that is as much like...

      (pp. 121-125)

      Perhaps the easiest way to identify an unknown grass is to take your specimens to an expert who will name them for you. Unfortunately, such individuals are increasingly rare. Another possibility is the “leaf method.” You leaf through a picture book or website until you find an illustration that seems to match your plant. The beautiful drawings in the two grass volumes of theFlora of North America North of Mexicocome immediately to mind. CalFlora, CalPhoto, and the Plants Database provide photographs. However, the standard method for identifying an unknown is to use a dichotomous key.

      A key is...

      (pp. 126-140)

      Plant families may be subdivided into subfamilies, and subfamilies into tribes. The internal classification of the grass family remains a very active focus of research, but significant differences in the interpretation of data exist. Recent molecular data have been very helpful in some instances, but less so in others. The system of subfamilies and tribes that I will summarize in this chapter is based largely on conclusions reached by the Grass Phylogeny Working Group (2001), Barkworth (2007), and Soreng et al. (2012).

      This subfamily is represented in North America by the single genusAristida(three-awn grass). Its 1-flowered spikelets led...

      (pp. 141-160)

      This key is intended to include all of the genera of grasses reported as growing in California that are native or are otherwise established and persisting without human assistance. Some of these grasses are not at all common and you are not likely to encounter them in the field. Several of them are known only from historic collections. Grasses falling into this category bear an asterisk. They receive only a very short description at the end of the key. All of the other entries are given a more complete treatment later in the book. Although most of the leads in...

  8. ACCOUNTS AND DESCRIPTIONS: Selected Genera and Species
    (pp. 161-396)

    Caespitose annuals. Stems to 80 cm tall. Inflorescence a single, balanced spike, the spikelets solitary at each node, typically with 1–3 rudimentary spikelets at the base. Spikelets typically oblong to ovate in side view, attached flatwise and fitting into the rachis, 2- to 8-flowered, rounded to ± laterally compressed, bisexual (the upper sometimes sterile), breaking apart below the glumes with a rachis segment attached or at the base of the spikes. Glumes 2, several-veined, 0- to 3-awned; lemmas usually 5- to 7-veined, awnless, mucronate, or 1- or 2-awned; palea keels ciliate. Mediterranean area and Asia. Goat grasses are completely...

    (pp. 397-414)
    (pp. 415-424)
  11. INDEX
    (pp. 425-437)
  12. Back Matter
    (pp. 438-438)