Family Poaceae (Gramineae)

the Grass family

          When thinking about the grass family, one might assume that a member of this family is what they see outside their homes, the green carpet they must mow every so often in the spring and summer months. What many don’t know is that the grass family is far more complex and beneficial to our planet. The grass family is the fourth largest flowering plant family, and most importantly, its economical value is highly demanded no matter where one lives. The grass family provides 80% of the global food source and contains 10 of the 30 most important crops (Evolution and Systematic of Grasses). Members of the grass family make up 20% of the world’s vegetational cover and are found anywhere from the humid areas of the tropics to the blistering cold areas of the Artic (Institute for Creation Research).
           There are 8000 different species of grasses in 500 genera. Of these species, 1200 are native to North America alone (Saint Louis County Health). Each of these species has characters that allow one to identify it in the grass family. Grasses are classified in the division Magnoliophyta, class Liliopsida, order Cyperales and the family Poaceae or Gramineae. Each of these names is correct when identifying the grass family. Gramineae was first used to identify members of the grass family but was later changed to Poaceae, although both are used today. Members of this family include lawn and forage grasses, bamboo, wheat, rice, rye, corn, sugarcane, and many more ecological and economical grasses (
          The grass family has many distinct characteristics that classify it into its own family. All members of the grass family have hollow stems called culms that are plugged at the nodes. They also have leaves at these nodes that have an alternate arrangement in a single plane; however, grasses are sometimes seen in spiral leaf variation. Since all grasses are monocots, one can also notice that all have parallel vein venation. In the grass family, the leaves and stems are not the only characteristics used for identification. Grasses also have a unique flower head. The flower head of a grass does not contain any sepals or petals. Instead, the flower is made up of borne clusters in an inflorescence known as a spike or tassel ( The inflorescence is subdivided into spikletes, which each contain one or more tiny florets. Among these florets, one will usually see three stamen and only one pistil with two stigmas (
           Each of these characteristics can be used to classify a grass down to its species, although roots can also be used for this purpose. There are two different ways of classifying a grass: sod forming and bunch forming. Sod forming is a process in which the grasses use rhizomes for reproduction from the parent plant. These rhizomes move horizontally through the ground and contact with other rhizomes to form asexual reproduction. This is commonly noticed in the grass family, because the root structures are fairly dense but do not penetrate deeply through the surface of the ground. This structure provides a large surface area coverage of the particular species, like its name, sod, suggests. Even though this structure is preferred by many species of this family, the bunch form is also seen. This specific classification of grasses has tillers that extend vertically into the soil, creating large clumps of grass. This is seen among many different species in which the grass is specific to its area and is usually in large numbers. In other words, the grasses of this particular structure are bunched together (AVIS Industrial Corporation and Taylor University Earth and Environmental Science Department).
           Identifying a member of the grass family is beneficial in identifying key characteristics that differ among other members. These specific differences are not only used to classify particular species, but some are also specifically useful in society. Grasses, among many other plants, have many economical, biological and environmental uses. Grasses such as wheat, rice, corn and many others are known as cereals. These cereals are mass produced and distributed around the world for food use. Many people use these cereals to produce flour, bread, porridge, oils, medicines, sugar and many other byproducts (Purdue University). Grasses are also used throughout the world in feeding domestic animals. Sorghum, timothy, bent grass and others provide pasture land and hay for these animals to graze ( Plants of the grass family are also used in the production of human resources including beer, liquors and other alcohols, such as ethyl alcohol which fuels automobiles, as well as newsprint and other types of paper. This just scratches the surface for the many uses of grasses. Grasses can also be used to prevent erosion of the soil; when degraded, the top of its roots are responsible for the rich black soil that is demanded by many farming communities (AVIS Industrial Corporation and Taylor University Earth and Environmental Science Department.). One type of grass, bamboo, is considered to be most useful plant known to man. The Japanese alone have more than 1500 uses for bamboo (Bamboo-Some Useful Facts). Bamboo is one of the very unique species of grasses because it is capable of growing an inch every 40 minutes, or 41 centimeters a day. It is also capable of reaching 36 meters, or the height of a ten story building (The Bamboo is also Grass). In many countries, bamboo grass is used for food, building materials, fuel, paper, furniture, plumbing and as weapons such as knives, bows, and arrows. Some use bamboo to build entire houses; in this case, every part of the bamboo is used (Bamboo-Some Useful Facts)..
         Grasses are by far one of the most useful plants on the earth. One of the secondary uses of plants relates to medicine. In the middle ages, there was a fungus that lived on the seed heads of cereals, known as ergot, or Claviceps purpurea, which was responsible for the loss of thousands of lives (Walker, 1998). This disease, called ergotism, also known as Saint Anthony’s Fire, was contracted when ergot was digested, causing many devastating symptoms that later resulted in death. If one had ergotism, the disease would cause them to begin to feel their skin burning and have uncontrollable twitching, extreme cramping, vomiting and diarrhea. Yet, this was not all; one might also start to develop gangrenous symptoms, and their flesh would literately fall from their body. This horrible disease, responsible for taking many lives, was later found medically useful for abortions and migraine headaches. It is even being considered in the treatment of AIDS and mental disorders. Today, there are several treatments and USDA standards to prevent this disease from infecting humans and animals (Pennstate University).
         As one can see, there are many different uses for grasses. Each species of the grass family contributes to some form of economical, ecological, and environmental need. Grasses are among the most important plant of the world and are used for many different things. Each species is unique in its own way, still following the true identification of the grass family. Many people and animals around the world survive off the production of the grass family; in fact, it is believed that if aliens were to land on this planet and took a quick look around, they would probably describe the planet as a place in which the grasses had millions of human slaves tending to their every need (Cornell University).

To view members of the Poaceae family visit Yellow Foxtail, Big Bluestem, and Indian Grass on the taxonomy camburn prairie home page.

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