Most Sheep Fescue sold commercially is not Festuca ovina, though much of it is labeld as such. These commercial fescues could all have been included in F. ovina when Hackel’s broad concept fo this species was accepted, but that hasn’t been true for the last 60 or more years. So what are commercial Sheep Fescues?
As horticulturalists became aware of that Festuca ovina was broken up taxonomicly, most recognized two species of bunch-forming fine-leaved fescues. The bluish ones were called Sheep Fescue, F. ovina, and the green ones were called Hard Fescue, F. trachyphylla. Actually, nearly all commercial Sheep and Hard Fescues are F. trachyphylla, a widely distributed European grass.
Before I go on discuss the commercial fescues that aren’t F. trachyphylla, I should mention a problem with the scientific name F. trachyphylla itself. The name F. trachyphylla was published twice for different species. Normally, the first publication is the only one that counts. In this case, the name was first used for a South American fescue. That would normally make it unavailable for the European species. However, there was an error in this first publication and some people argue that the name was therefore available to be used for the European grass. If that is true, this grass should be called F. trachyphylla. If the mistake was trivial, however, we have to call it something else. If so, it should be called. F. brevipila. Probably. There are some people who think that this commercial fescue should be considered the same as the wild F. longifolia of Great Britain. If that is true, the much earlier name F. longifolia should be used for our commercial Sheep and Hard Fescues, but other botanists argue vehemently against this. Personally, I use the name F. trachyphylla because Stephen Darbyshire, a recent authority in the group, thinks it’s the right name and I don’t care.
Are there any “Sheep Fescue” that aren’t F. trachyphylla? Yes. I know two and suspect that others are coming into use recently.
Quatro Sheep Fescue, developed for golf courses, is real F. ovina. (Yes, it’s green; don’t let that bother you.)
Covar Sheep Fescue is F. valesiaca, developed from Turkish seeds. Covar is very tolerant of dry conditions. It is widely planted on roadsides in eastern Oregon and is sometimes planted for pasture renovation. I expect more cultivars to be developed from drought-tolerant F. valesiaca. Covar tends to spread slowly into surrounding habitat. Vegetatively, it looks a lot like F. idahoensis, but it can survive on dry, sunny, south-facing slopes where F. idahoensis would die. When fertile, Covar has much more dense inflorescences than F. idahoensis.
As a “handy” wasy to tell them apart, Covar is diploid, the F. trachyphylla cultivars are hexaploid, and I believe Quatro is tetraploid.