All fescue varieties are not the same
In fescue seed advertisements, one may see terminology like “endophyte-free, friendly or novel endophyte, beneficial endophyte or toxic endophyte.” Some ads may not mention an endophyte at all. All fescue varieties are not the same; therefore, producers need to have a clear understanding of the differences among varieties and types, especially as they relate to the endophyte.
Tall fescue is a versatile perennial grass used for livestock feed, turf and erosion control. Commonly referred to simply as “fescue,” it is easy to establish, tolerant of a wide range of management regimens and a good forage yielder. Laboratory nutritive analyses of fescue compare favorably to those of other cool-season perennial grasses. Fescue was first planted on a widespread basis in the USA in the 1940s. However, in the late 1970s it was discovered that in most of this acreage a high percentage of fescue plants were infected with an endophyte. “Endophyte” means internal fungus; it grows inside fescue plants. Soon thereafter it was learned that this endophyte can produce toxins (specifically, ergot alkaloids) that can have profound negative effects on grazing animals. However, the endophyte has positive effects on the grass itself. Anyone who uses tall fescue to provide nutrition for grazing animals needs to know about the fescue endophyte.
Toxic Endophyte Fescue
This refers to tall fescue that contains the wild type of endophyte that infects most of the millions of acres of this grass established in the United States beginning in the 1940s. Toxic endophyte fescue produces toxic alkaloids that cause animal disorders.
This term refers to tall fescue that does not contain an endophyte. If there is no endophyte, then there will be no endophyte-related toxic alkaloid production, and thus endophyte-free fescue is non-toxic. However, endophytes also produce compounds that favor pest resistance and stress tolerance of fescue plants, with the result being that endophyte-free types have not been as persistent as endophyte-containing types in stressful environments and are not recommended for Missouri.
Novel Endophyte Fescue
In the late 1990s, scientists identified strains of the tall fescue endophyte that do not produce the alkaloids that cause animal disorders (Fig. 1). However, novel endophytes do produce compounds that favor pest resistance, grazing tolerance and persistence in stressful environments. Therefore, cattle performance is excellent with novel endophyte fescue.
For more complete information on the tall fescue endophyte, go to: https://forages.ca.uky.edu and search for “Understanding the Tall Fescue Endophyte.”
~ Pennington Newsletter, The Fence Post, Spring, 2022
The Alliance for Grassland Renewal is a national organization focused on enhancing the appropriate adoption of novel endophyte tall fescue technology through education, incentives, self-regulation and promotion. For more resources or to learn more about the Alliance for Grassland Renewal, go to www.grasslandrenewal.org