How a Grass Plant Grows
We enjoy our lawns, playing on them, and watching them grow. We may never really take the time to look at how they grow and develop.
All turfgrasses grow from a ground-hugging growth point, an area at the base of the plant called the crown. Our mowers clip the grass and as long as the crown is not damaged, the plant continues to grow. Roots and shoots originate from the crown. Below the ground there is a fibrous root system. For bluegrass these roots usually go down about six inches. Fescue grass roots extend about twelve inches deep. Turf type fescue grasses are being incorporated into new lawn seedings because of this drought tolerance due to deeper roots.
The roots take in nutrients and water from the soil and anchor the plant. Above the ground the stem and leaves take in light and carbon dioxide. Extending from the crown are the shoots or leaves. A leaf consists of a blade and a sheath. The blade is the broad upper portion, and the sheath the lower portion that encircles the stem. The sheath remains wrapped around the stem while the blade unfurls and grows upward.
The sheath and the blade meet at a point called the collar. Inside the collar is the ligule, a thin membranous band or ring of hairs, which ends in ear-like lobes called auricles. Together, the size, shape and makeup of the liguales and auricles provide valuable clues for identifying a grass.
Tillers are secondary shoots that also grow from the crown. As they expand, they help make a lawn thick and full. All grasses exhibit some tiller growth. Some are called bunch grasses because their tiller growth arises from the crown. Examples of these are the fescues and ryegrasses that form thick clumps as they expand and fill a lawn. Other grasses, called creeping grasses, spread primarily by specialized stems called rhizomes or stolons. These extend horizontally from the crown of a parent plant. Examples of grasses with rhizomes are bluegrass and bromegrass. Examples of stolons are buffalograss and zoysiagrass.
Remember, the incredible turfgrass plant is unlike anything in your landscape. Understanding it’s structure and growth helps you build a foundation for better lawn care.
Chris Carlson, Extension Educator, March 2003
|
