David M. Kopec, Extension Turfgrass Specialist
No, it's not really a report card, but if you are buying seed for lawn or pasture that contains either perennial ryegrass (Lolium perenne) or tall fescue (Festuca aurundinacea) , you would be best to check out the following.
About fifteen years ago, forage scientists in Missouri and Kentucky and turf scientists at Rutgers were discovering that a certain fungus living inside tall fescue and perennial ryegrass plants was associated with certain animal or lawn characteristics.
In pasture grasses, horses, cattle and sheep that fed on plants which had the fungus inside the leaves showed symptoms of poor hoofs, poor skin coats and fur, elevated body temperatures and scaly facial skin. At just about the same time, turfgrass scientists demonstrated that experimental grass lines which had persisted for years and years (right next to others which died) contained an internal fungus. What was the relationship? It turns out that the fungus inside (endo) the plant (phyte) caused the plant to produce compounds which have biological activity on pests (insects). That's why the infested turf plots lived year after year -- they had no insect predation because of the endophyte. The reason why the animals that ate infected plants showed symptoms, was that the infected plants dominated the pasture for years and years -- just like the turf plants did.
Biologically, the fungus is call an ENDOPHYTE. There are several genera of fungi that cause the endophyte reaction. Research in the last ten years has taken the following paths.
Forage: Plant breeders have selected and breed for tall fescue and perennial ryegrass having NO ENDOPHYTE. That is the seed you plant is E- or endophyte free. Ask the seed dealer if the seed is (1) endophyte free, or (2) what percentage of the seed contains endophyte. Seed for pasture should have no more than 10% endophyte. The endophyte is not transmitted by pollen, rather it lives in the "mother plant" which passes it off in the seed food reserve (endosperm). Therefore, pasture seed of ryegrass and tall fescue should be (E-) or endophyte free.
Turf: Non-edible (turf) grass benefits from being ENDOPHYTE infected. The compounds that are induced inside the plant repel or limit the biological activity of above ground feeding insects. These include sod webworms, armyworms, cutworms, stem weevils, chinch bugs and aphids. However, it has no effect on root eating grubs. This is "free" integrated pest management. When buying tall fescue or ryegrass seed for lawns ask if (1) the seed contains endophyte (E+) and if so (2) what percentage of the seed contains the endophyte. High endophyte turf seed of tall fescue and perennial ryegrass will contain 80% or more endophyte. The label will say "ENDOPHYTE ENHANCED SEED!"
E+ = endophyte enhanced = good for turf.
E- = endophyte free = good for pasture.
Take score next time you go seed shopping for the lawn or the farm!!
Issued in furtherance of Cooperative Extension work, acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, James A. Christenson, Director, Cooperative Extension, College of Agriculture & Life Sciences, The University of Arizona. The University of Arizona is an equal opportunity, affirmative action institution. The University does not discriminate on the basis of race, color, religion, sex, national origin, age, disability, veteran status, or sexual orientation in its programs and activities.