Method of Breeding - The first crosses were made in 1962, involving, as parental varieties: Aries, Russian No. 27863, 2 Icelandic Numbers, Szehass - File, soft leafed CB and Roskilde lines. Forty-five families were selected from the crosses on the basis of yield and persistence.
Intended Use - Hay and pasture production.
Description - Growth habit is medium to semi-erect; spring growth is early to medium. Leaves are medium green; mature plant height is tall; heading date is earlier than Prairial or Sumas; maturity is medium early. European data indicate Amba is resistant to purple eye-spot and susceptible to leaf rust and yellow stripe rust. Amba performed well for forage as compared to the check varieties in western Canada. In Europe, Amba exhibits good winter-hardiness, seed yield and good digestibility.
Adapted to - Recommended in Canada for use in British Columbia.
Released - Danish Plant Breeding Ltd., Boilshoj, Denmark. Registered in Canada in 1986 as registration no. 2623.
Breeder Seed/Stock - Danish Plant Breeding Ltd., Boilshoj, Denmark.
Certified Seed/Stock - Available.
Preparer/Additional Information - Agriculture Canada, Food Production and Protection Branch, Plant Products Division, Ottawa, Ontario K1A 0C6. Seed is distributed by Topnotch Nutri Ltd., P.O. Box 1030, Abbotsford, British Columbia V2S 5B5.
So, at least two out of three of those varieties appear to be exotic, and I would hazard that the last of the three could be a problem for you if it gets out of hand by virtue of its high productivity and late season drought tolerance. Unless you have a lot of land and a way to control it, I would be careful.
Which brings me to your purpose in selecting the seed. For example, if it is simply to be a cover crop for an orchard, there might be better choices that don't compete so successfully with the trees for water. If your purpose is to provide forage for grazing animals such as horses, you probably have made a good choice as long as it doesn't get out of hand and cause your neigh-bores (sorry) a weed problem.
If your purpose is to cover for grading, some of the native grasses are probably better in the long run, but they are pricey. Elkhorn Native Plant Nursery has the best price and selection on those in this area. Good people.
I take it back (I misread my flora). Orchardgrass is also a European exotic. Interestingly, it is listed in my 1961 Flora of the Santa Cruz Mountains (which you might want to purchase while it's still in print, ISBN 0-8047-0017-6) as having been recorded in Glenwood, near where we live.
So, all three of those grasses are exotic species.