Cool-climate grasses are the types most suitable for use in the northern sections of the country, including the northeastern, northern, midwestern, and northern Pacific coastal areas.
In these climates, winter temperatures go down to zero or below; and the summers, while hot, do not normally have exceptionally long periods with no rainfall.
The perennial grasses that grow in them begin vigorously in spring and continue until early or midsummer.
They mature if left to grow normally, in June to early July, and then take a midsummer rest during July and August.
Vigorous growth is renewed in late August or September. Still, it is of a character different from the spring growth, the individual plants tending to “tiller” or spread horizontally instead of sending up tall, flowering, seed-bearing stalks.
Some grasses tend to spread or creep, and others form tufts or clumps. They are quite generally used in mixtures, as the resulting turf, under most conditions, requires less constant and expert care than do single grass turfs of Bent or Bluegrass.
Bentgrasses (Agrostis)
Bentgrasses make the most beautiful turf, forming a dense, fine mat of rich, green color.
They are used for golf courses and smooth, close-clipped lawns on large estates where they can receive the constant care they need: moderate fertilization, frequent top-dressing, deep watering, close mowing (from ¼” to 1 ¼” inches), and disease control.
Because all the Bents are not susceptible to the same diseases, the planting of mixtures of several sometimes resorts to assure good coverage.
Ten percent of Colonial Bent (a dependable, non-creeping form) is often used in good cool-climate grass mixtures where a fine lawn texture is preferred.
Bentgrasses do best with a soil pH of 5.5 to 6.5 (slightly acid) and well-drained loam. Most of them endure little shade.
Colonial Bent
Colonial Bent (A. tenuis) is available in many improved strains developed in different sections of the country to suit special conditions.
Among the best known are Arlington, Astoria, Congressional (susceptible to dollar spot), Highland (drought resistant), New Zealand, Oregon, Penncross, Pennlu, and Rhode Island.
This species and its varieties grow well only in full sun. Use 2 pounds of seed per 1000 square feet, and buy certified seed.
Creeping Bent
Creeping Bents (A. palustris varieties), commonly used for putting greens, are lighter in color than Colonial and require cool, moist conditions and high fertility, but they have some shade tolerance.
They grow by creeping stems and are quite resistant to salt spray, so they are sometimes used as lawn grasses near the seashore, where they prosper naturally.
Because they are susceptible to certain diseases (snow mold, dollar spot, and brown patch), they are not generally recommended for lawns, as disease control measures must be taken regularly.
They also require very close cutting—½” to ¾” inch. Recommended strains include Cuckoos, Metropolitan, Washington, and Seaside. Seeds of the last name can be had commercially, but others must be started from stolons or sprigs.
Redtop
Redtop (A. alba) is a much less demanding grass than the other Bents, accommodating itself to hot or cool conditions and with a fair shade tolerance.
The color is light to bluish-green and, when mature, the texture is coarse, quite unlike other Bents.
It is short-lived however and, as it germinates quickly and is fine textured in the seedling stage, 10% percent of Redtop is often used as a “nurse” grass in a mixture to make a temporary green cover until the more permanent grasses (such as Colonial Bent or Kentucky Bluegrass) become well established.
By that time the short-lived Redtop had disappeared. Since, like other Bents, it is susceptible to snow mold and brown patches, large percentages of Redtop should not be used in mixtures.
Velvet Bent
Velvet Bent (A. canina) endures heat and cold well; it is somewhat shade and drought-tolerant but requires plenty of fertilizer.
It produces a dark green, fine-textured turf of fairly long life. Like Creeping Bent, Velvet roots at the nodes or joints and is useful chiefly on putting greens.
As it is disease resistant, except for copper spots, it has distinct advantages in areas where it grows well.
Bluegrasses
Bluegrasses (Poas) Bluegrasses are highly prized for cool-climate lawns. Kentucky Blue and its varieties form the backbone of the average, good, permanent lawn mixtures in cool-climate areas, while other Poas are useful for special conditions.
Kentucky Bluegrass (Poa pratensis) is a rather fine-bladed grass, deep blue-green, which spreads by underground rootstocks and forms a somewhat open turf of medium texture.
Though slow to germinate, once established, it is long-lived, making a permanent lawn. It requires full sun, neutral or slightly acidic soil (pH 6.0 to 7.0), plenty of fertilizer, and water.
Kentucky Blue or one of its improved strains can be planted alone if desired in areas where it grows well.
Depending on location and special conditions, mixtures containing from 80% to 30% percent produce a green turf more quickly than a 100% percent Bluegrass lawn.
Merion Blue
Merion Blue, a variety discovered on the Merion Golf Course near Philadelphia, is generally recommended as the best Kentucky Blue available. It is more vigorous, deeper rooted, and disease- and drought-resistant than common Kentucky Blue.
Its shade tolerance is higher, and the color is deeper and is maintained over a longer period. It can also be mowed more closely (½” to 1 ½” inches) than the Kentucky Blue.
The Turf Research Foundation recommends that at least 40% percent of Merion Blue be included in any seed formula containing this grass.
It should be fall planted, from mid-August to mid-September, as germination is slow. Using straight Merion Blue seed, 2 to 3 pounds should be sown to every 1000 square feet for the average home lawn.
Under ideal conditions, 1 pound per 1000 square feet is sufficient. If possible, use a seed spreader. A well-established Merion lawn needs little artificial watering. Buy certified seed.
Canada Bluegrass
Canada Bluegrass (Poa compressa) is a deep-rooted, coarse, scraggly hay grass that tolerates poor soil and shade with plenty of moisture.
Though unsuitable for lawns because of its coarse texture and short-lived if kept mowed, it is useful on polo and athletic fields where conditions are suitable and where it can be cut very high (3” to 4” inches) and very infrequently.
Rough Bluegrass or Meadowgrass
Rough Bluegrass or Meadowgrass (Poa trivialis) prefers fertile soil and damp shade, where it produces a light green, low-growing carpet.
It is highly recommended in many sections as a shade of grass. From 80% to 30% percent is often included in shade mixtures. Sow at the rate of 3 pounds per 1000 square feet.
Wood Bluegrass
Wood Bluegrass (Poa nemoralis) is a low-growing, shade-loving grass that does not creep. It is occasionally used as a substitute for Poa trivialis.
Fescues
Fescues (Festuca) Fescues make sturdy turf that can take rough treatment. They thrive in sun or shade, endure moist or dry conditions, and can get along on soils of comparatively low fertility, though they appreciate a good loam.
These grasses are slow growing, of a stiff, wiry but fine texture, and deep green. They prefer a pH of 5.5 to 6.5 but can survive considerable acidity. Mowing should be 2” to 3” inches in height.
Red Fescues
Red Fescue (F. rubra fallax) or one of its improved strains—Chewings Fescue and Penn State Chewings, Pennlawn, Ulahee, and Trinity—produce tight, wiry turf and are used at rates of 50 to 30 percent in most cool-climate grass mixtures.
Chewings are susceptible to humidity, heat, and diseases, such as pink patches and anthracnose, so it pays to purchase one of the improved strains which grow well in your area and which have been developed for disease resistance.
Two to 6 pounds of seed are required per 1000 square feet, increasing the poundage for dry, sandy soils.
Meadow Fescues
Meadow Fescue (F. elatior), a bright green perennial species, may be added as a temporary nurse grass to shade mixtures where the soil is deep and rich. It is a heat- and drought-resistant species.
Sheep Fescues
Sheep Fescue (F. ovina) is a northern bunch of grass that forms dense bluish-gray tufts and is sometimes used for turf on sandy soils in the Northeast and Pacific Northwest where the soil is sandy, and other lawn grasses do not succeed.
Tall Fescue
Tall Fescue (F. elatior arundinacea) and its strains, Alta and Kentucky 31, produce better turf for play areas, athletic fields, airports, etc., then Chewings or Creeping, especially in areas where they have to contend with heat, high humidity, and disease.
They are not generally recommended for lawns but grow well on humus-rich, sandy, or clayey soils—wet or dry—if well fertilized. The mowing height is 3 inches.
Ryegrass
Ryegrasses (Lolium) Ryegrasses are of two sorts—annual and perennial. Their texture is medium coarse, with broad, shiny leaves, the color dark green.
They are happy in cool or hot weather, prefer well-drained, heavy but fertile soil, and endure drought well. All are seeded at the rate of 5 pounds per 1000 square feet. Germination is rapid.
Domestic or Italian Rye
Domestic or Italian Rye (L. multiflorum), the annual species, is used at the rate of 20 to 10 percent, chiefly as a nurse or temporary grass to give a quick effect in seed mixtures until the more permanent species take over. At this time, the short-lived Ryegrasses are crowded out.
They are also useful for temporary lawns and for winter “over planting” of southern summer grasses like Bermuda and Centipede. When used alone, sow at the rate of 4 to 5 pounds per 1000 square feet.
Perennial Ryegrass
Perennial Ryegrass (L. perenne) is a quite long-lived species and makes a permanent, coarse turf in areas where it grows well. It endures shade much better than annual Ryegrass and is drought-tolerant.
Often it is spring planted as a temporary new lawn, to be turned under as green manure in August or even a year or more later when the homeowner is ready to seed his permanent turf.
Or planted in early autumn, it gives a green lawn through the winter and the following summer and can be turned under in August, to be replaced by a mixture of the better permanent grasses. Seed at the rate of 4 to 5 pounds per 1000 square feet.
Clover, White Dutch
Clover, White Dutch (Trifolium repens), though not a grass, is often used in grass mixtures, especially in areas where Crabgrass or disease depletes the fine grasses. It will grow anywhere in the United States where it can be given sufficient moisture.
Clover prefers neutral or slightly alkaline soil and plenty of moisture and does well in either full sun or part shade.
Because it is a legume that builds up nitrogen in the soil, it helps to feed the grass plants with which it is associated. In a mixture, it is used at the rate of 2 ounces per pound of grass seed.
44659 by F. F. Rockwell And Esther C. Grayson