Should the dust, when applied, drift onto ornamental plants or onto vegetables, or to a pond where there are gold fish, serious injury will result.
However, used with care, these selective weed killers have an important place in weed control in lawns. Weeds are best controlled when they are in active growth and when the temperature is high and there is plenty of soil moisture. They are more difficult when they reach the mature, or seed stage.
Crabgrass is now being treated with various chemicals which, under certain conditions, are giving various degrees of success. This is an annual grass. The plant itself, unlike our regular grass, is killed with the first frost. But the seeds live over. These begin growth when the weather gets warm in June. There are three kinds; one of them grows flat against the ground and is extremely difficult as the blades of the mower cannot catch it. Seeds are formed in late August, drop in late September when the grass turns an ugly reddish brown.
Grasses for Southern Lawns
Bermuda grass is the most commonly used because it is always available as seed. The seed is planted in March or April, using one-quarter lb. per 100 square ft. It has a tendency to die out in winter; consequently, spring seeding is best. Perennial ryegrass is roughed in for the winter to give a green covering. Bermuda grass lawns are also started by laying sods or by sprigging (small pieces planted several inches apart). This grass will not tolerate shade.
Centipede grass is a low-maintenance grass. It will tolerate acid sandy soils, requires the minimum of fertilizer and is relatively free from insects and diseases. Quick to become established, it is easy to mow. However, it will not grow in shade or on an alkaline soil and it turns brown in winter. There is no seed available, a lawn must be planted by sprigging.
St. Augustine grass, most popular throughout Florida, remains green the year round and grows quickly to become established. To endure it must have liberal applications of fertilizer, water and pest control materials. It is the best grass for shade and it will grow equally well in acid or alkaline soils. It cannot be obtained as seed. Again, lawns are made by sprigging.
Carpet grass is used in some parts of the South in moist sandy soils. It will grow in shade. This grass can be established from seed sown in fall, winter or early spring. Use one-quarter pound per 100 square ft. The seed stems on this grass are hard to cut and they are freely produced. The lawn, too, has a ragged appearance.