Grasses make up 70 percent of our crops and 50 percent of the calories that humans consume. We should give the humble grass a little more respect.
“Life often depends upon the little things that we take for granted.” I don’t know who said that, but it certainly applies to members of the grass family. We walk on grass, we cuss it when its pollen makes us sneeze, but mostly we just ignore it—and fail to recognize the essential role of grasses in our lives.
Members of the Order Cyperales, often referred to as the graminoids, include three families: the sedges, rushes and true grasses which are members of the Poaceae family. Poas, as true grasses are often called, are amazing plants that have been on this planet for over 60 million years. Grass dominated biomes such as pampas, steppes and prairies, cover 31 percent of the plant’s land mass and account for 20 percent of all the vegetative cover on earth. They can be found in virtually every corner of the earth as well, with the exception of the center of Greenland and much of Antarctica.
With 10,000 species of grasses, it is expected that they can assume many life strategies. There are annual, biannual and perennial grasses. There are herbaceous and woody grasses and land and aquatic grasses. Some are evergreen while others die back each fall. There are grasses that grow in bunches and grasses that form ground covering sod. Some grasses may only grow an inch or two high while others compete with the trees for sunlight.
However, all grasses share common traits as well. They, along with other graminoids, are monocots. When a seed sprouts, it sends up only one leaf. Grasses also have hollow round stems and leaves far longer than wide with parallel veins. The leaf wraps around the stem in a cylindrical sheath with a long blade above it.
Grasses have been cultivated by humans for at least 10,000 years. We grow grasses for livestock feed but we are also quite dependent on them for our own direct sustenance as well. Just three grasses: wheat, rice and corn, provide over half of the calories humans consume on this planet. Seventy percent of our crops are grasses as well.
Besides the cereal grains which also include barley, oats and millet, there are other grasses that yield products that humans find irresistible. For instance, sugar cane and sorghum (used for sugar production, fodder and alcoholic beverages) are grasses. Bamboo is also a grass. It is eaten by the world’s favorite wildlife species, the panda bear, but is also strong enough to be used as scaffolding and flooring.
Here is the amazing secret about grasses and one that has made them wildly successful and extraordinarily valuable to humans: Grass leaves grow from the base of the blade and not from the stem tips. This allows grasses to be grazed or mown regularly without severe damage to the plant. This trait evolved with wild herds of grazing mammals and sustains the domestic herds of today.
We may take grass for granted, but humans would not survive long without the humble grass family.