LOW MAINTENANCE TURFGRASSES FOCUS ON FINE FESCUE
Craig W. Edminster1
The United States turf industry has treated these bristle like, shade tolerant, fine textured species as a homogeneous group for years. Despite the similar appearance, fine fescue differs both morphologically and in agronomic characteristics such as drought resistance, disease susceptibility, tolerance to close continuous mowing, turf color and compatibility with other cool season grass species.
The fine fescues (Festuca spp.) consist of several species of cool-season turfgrasses that do not require intensive management. Fine fescues have fine to very fine leaf texture and are generally considered to be shade tolerant, drought tolerant and require little or no additional inputs of fertilizer or supplemental irrigation (Ruemmele et. al., 1995). They include, but are not limited to, chewing fescues (F. rubra L. subsp. commutata), hard fescues (F. longifolia), and sheep fescues (F. ovina), F. pseudovina, and blue fescues (F. glauca); and the rhizomatous types: slender creeping red fescue (F. rubra L. subsp. tricholphylla) and strong creeping red fescue (Festuca rubra L. subsp. rubra).
Fine fescues are difficult to differentiate for even the most proficient turfgrass professional. Their close morphological resemblance and existence of numerous ecotypes makes fine fescue species identification and classification a difficult problem for turfgrass scientists and taxonomists. Huff and Palazzo, 1998, using a laser flow cytometer have provided a better understanding of ploidy levels and proper classification of many of the Festuca species used for turf and amenity purposes in North America. Table 1. This information will also aid plant breeders in accurately and easily determining primary breeding germplasm with respect to ploidy level.
Measurable differences among and between species may be based on leaf blade anatomy, leaf sheath morphology, or root florescence (Hubbard, 1984). For example, chewing fescue is easily separated from the creepers based on the absence of intervaginal stems (rhizomes). Morphological differences between the two creepers are more difficult to distinguish, being based on quantitative differences in rhizome diameter and rhizome biomass production (Schmit et al., 1974). Management and cultural practices in turf are very different among and within the family of fine fescue. Successful turf managers are encouraged to fully understand the differences among fine fescue and their adaptation to standard turfgrass management and cultural practices. A summary of some of the differences is attached for your review (Tables 2 & 3).
|SPECIES||PLANT HTS||LHC TOL||ENDOPHYTE||THATCH||SEEDS/LBS|
|Chewing||3.0 ft||V. good||Yes||High||365,000|
|Strong crp||3.0 ft||Fair||Yes||Low||400,000|
|Slender crp||<2.5 ft||V. good||No||High||450,000|
|SPECIES||PLANT TYPE||TURF QUALITY||SPRING GREEN-UP||SEEDLING VIGOR||RED THREAD RESISTANCE||SALT TOL mmhos||ET RATE mm|
1-9= best, rating for relative performance across USA. NTEP summary results 1984-1998
Chewing fescues have a bunch-type growth habit, form a denser turf than the strong creeping red fescues, and tend to be more disease resistant and persistent under lower maintenance. Of the fine fescues, chewing fescue is the most tolerant of close, continuous mowing, traffic pressure and has some application in sports turf. Where can chewing fescue be used? In the Pacific Northwest perennial ryegrass is often mixed with chewing fescue in a 70/30 ratio for shaded lawns and park areas. In the central U.S. new golf course construction projects seeding bentgrass to the fairways include chewing fescue as a nurse crop to discourage "take all" incited by Gaeumannomyces. Chewing fescue is also used in winter overseeding programs where rapid spring transition is desired.
Both the strong and slender creeping red fescues have rhizomes and a spreading growth habit that produces a more open turf. One significant difference between these two species is that the slender creeping red fescues have fewer, shorter and more prolific rhizomes than do strong creeping red fescues. The strong creepers also tend to be more tolerant of patch and crown disease and are often mixed with Kentucky bluegrass and perennial ryegrass in hot and humid regions. Strong creeping fescue is often a component in northern region turf mixtures with perennial ryegrass, Kentucky bluegrass and tall fescue. Strong fescue is the most compatible of the fine fescue in mixtures with other cool-season grasses. The slender creeping red fescues are very tolerant of saline soil conditions, respond well to low mowing heights and can be used in winter overseeding programs where rapid spring transition is desired. Slender creeping red fescue is often used as a component in roadside turf mixtures where salting of roadsides is required. Slender creeping fescue is also used in maritime climates in tee box mixtures where low height of cut is often required.
Sheep and blue fescue possess stiff bunch type, non-creeping growth habits, bluish-green to dark green leaves, require little maintenance and do poorly under intensive cultural management practices. Sheep and blue fescue are often used in wildflower mixes because of their non-aggressive ornamental appearance. Sheep fescue is often used as a component in low maintenance turf mixtures where a "windswept" or links look is required. Sheep fescues also are used for wildflower mixtures and in some cases, depending on variety, for low maintenance turfgrass applications. Blue fescue is used extensively for ornamental landscape plantings.
Hard fescues are similar in appearance to sheep and blue fescue, but have wider, tougher, less bluish leaves and are more tolerant of higher fertility and moist soil conditions. Improved varieties of hard fescue are more similar to chewing fescue with similar turf density and texture, but lower nutrient requirements and slower vertical growth rates. Hard fescues are also used as a component in low maintenance turf mixtures where a "windswept" or links look is required. Hard fescues are also used for wildflower mixtures and in low maintenance turfgrass mixture applications.
Fine fescues are more tolerant than other cool-season grasses to doughty, infertile, acidic soils and shady sites. They are intolerant of poorly drained, wet soils and high fertility. Fine fescue will persist in sites where cultural inputs are minimal or nonexistent and will with compete with other cool season grasses when sunlight, nutrients, and water are limited. Once established they can often survive for years without fertilization, supplemental irrigation or pesticide application. Over fertilization and close continuous mowing can reduce fine fescue populations in turf or mixed species turf by reducing heat tolerance during summer stress. High nitrogen contributes to more succulent plant components, resulting in decreased resistance to insects and disease. Fine fescues that contain Neotyphodium endophyte possess enhanced stress tolerance and resistance to disease and insects. Neotyphodium is a fungus that lives symbiotically within plant tissues. In exchange for nutrients, the endophyte produces compounds that improve the plant's resistance to external stresses.
Cebeco International Seeds, Inc. is a supplier of Longfellow, Longfellow II and Darwin chewing fescue, Cindy and Herald strong creeping red fescue, Eureka and AnvilŪ hard fescues, Quatro sheep fescue, and Marker slender creeping red fescue.
1Craig W. Edminster, Director of Research, Cebeco International Seeds, Inc., Halsey, OR 97348. Presentation at 5th Annual Minnesota Truf & Grounds Foundation Conference & Trade Show 12/9-11/98 Minneapolis, MN.