WE KNOW TURF: Mowing

PROPER MOWING IS ESSENTIAL

Grass mowing is a major time consuming operation in the maintenance of any turf grass area. Good mowing practices are an important factor contributing to a well-groomed appearance and the longevity of any turf grass area. The manner in which grass is mowed will greatly influence its health, vigor and density.

GROWTH HABITS AND CHARACTERISTICS

On the basis of growth type, grasses may be classified into three general groups: bunch type grasses, such as ryegrass and chewing fescue; stoloniferous grasses, such as creeping bentgrass; and rhizomatous grasses such as Kentucky bluegrass. Some grasses, such as bermudagrass and zoysia, spread by both rhizomes and stolons.

The grass leaf is remarkably adapted for intercepting a maximum of sun rays which are essential for photosynthesis. The long, flattened grass blades provide a maximum of exposure with a minimum amount of protoplasm, thus making efficient use of the living plant. A reduction in the plant leaf area exposed to sunlight reduces the plant's capacity to carry on photosynthetic activity. This is a vital and basic consideration in determining the frequency and height of cut of turf grasses.

The ability of grasses to withstand frequent and relatively close cutting is related to certain peculiarities of the grass family. Grasses exhibit basal growth, as opposed to terminal growth, found in most other plants. Basal growth means simply that growth initiates at the base rather than at the tip of the blade or stem. From a practical standpoint, this means that normal and frequent mowing does not cut off the growing areas of the grass leaf. Removal of too much leaf surface at any one cutting may, however, destroy some of the growing points.

HEIGHT OF CUT

The height at which a given perennial grass can be cut and still survive for extended periods is directly related to its ability to produce sufficient leaf surface for the photosynthetic activity required for its growth. turf grass species vary greatly in tolerance to cutting height. The cutting height tolerance of a given species or cultivar is a function of the growth habit characteristics.

SUGGESTED RANGE OF CUTTING HEIGHT

FREQUENCY OF CUT

Frequency of mowing is an important consideration in the maintenance program. Infrequent mowing allows the grass to elongate to such a degree that any subsequent mowing removes an excessive amount of leaf surface. At no time should clipping amounts in excess of 1 /4 to 1 /3 of the total leaf surface be removed at a given mowing. Removal of larger amounts of leaf surface will result in a physiological shock to the plant, cause excessive graying or browning of the leaf tips, and greatly curtail the photosynthetic production of food with a resultant depletion of root reserves. In addition, the accumulation of excessive clippings may smother the grass and provide excellent environmental conditions for disease organisms and insects.

STATE OF GROWTH

The stage of growth of turf grass plays a major role in mowing practices. Young, tender growth in the Spring is generally soft and succulent. The moisture content of young, immature turf grass is much higher than that of mature grass. Tender young grass must be cut with a very sharp, well adjusted mower to avoid mechanical damage, and the early growth must be cut frequently to avoid the problems associated with high moisture.

Mowing wet grass should be avoided as much as possible. Dry grass cuts more easily, does not ball up and clog the mower and gives a much finer appearance.

Mowing practices during the early stages of growth exert a material influence on the density of turf grass. Cutting heights slightly lower than normal during early Spring will encourage lateral growth which, in turn, promotes density and helps prevent weed invasion.

SELECTION OF THE MOWER

The proper type and size of mower is important in maintaining any turf grass area. Good mowers are characterized by high maneuverability, easy adjustment, durability and adequate horsepower for the size and usage expected.

Four basic types of mowers are available - reel, rotary, sickle bar, and vertical. Choice of a given type will be governed by the particular duties the unit will be expected to perform. Each type has certain advantages and limitations which should be carefully considered before final selection of the mower is made. Mowing is not a simple operation to be regarded merely as a means of removing excess growth.

It is a maintenance practice which has a far-reaching effect on the appearance and long life of any turf grass area.

It is essential that all types of mowing equipment be kept sharp and in good operating condition. Dull, improperly adjusted equipment not only destroys the aesthetic value of the area, but also bruises the leaf tips, thus providing ready access for diseases and insects.