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GRASSES
OF THE COLUMBIA BASIN OF BRITISH COLUMBIA
A hybrid is the offspring of two different parents, varieties or species that differ in one or more heritable characteristics (Woodland, 1997). Most often the cross occurs between two different species, but it can occur between two different genera, species, subspecies or varieties. Grass biologists have recognized that a certain amount of hybridization occurs in nature between species that have overlapping ranges, and therefore many of the subspecies and varieties recognized are actually hybrids. How widespread is this interbreeding in natural populations? In the past few years research has indicated that this natural hybridization is widespread and important, certainly within genera, but how important is hybridization between genera? Plant breeders artifically cross different genera due to the increased economic value in the new species. In fact, many of the commercial grass mixtures are the result of crosses conducted to breed certain characteristics into the "new" grass. For example, the forage grass Kemal is of hybrid origin from Festuca pratensis and Lolium perenne. In many cases these hybrids are unable to naturalize and remain isolated to areas where they are continually planted. But in other cases, these artificially created hybrids do naturalize and interbreed with natural populations creating identification problems. So far, natural hybrids between genera have not been recognized, but several authors have recognized X Elyhordeum macounii as a commonly occurring sterile hybrid between two well known genera, Elymus trachycaulus and Hordeum jubatum.
Flowerhead and Flowers: The plants are sterile hybrids and the anthers do not open, even at maturity, therefore remaining attached when they should have withered and disappeared. In areas where forage crops are regularly planted, a number of hybrids have been noticed but not formally recognized in Canada, despite being recognized in England. Two of these have been observed to occur in the Columbia Basin region at Rock Creek -- X Festulolium braunii and X Festulolium loliaceum. It is most likely that they were planted together as a combined seed mix. In the future it will be interesting to note whether these hybrid species actually occur elsewhere in British Columbia, since they have naturalized in England.
Leaves and Stem: The sheath is smooth and the membranelike ligule is up to 1 mm long. The small, spreading auricles are smooth. The flat leaf blades are hairless, 7 mm wide and can be rough along the edges. Flowerhead and Flowers: The flowerhead is 10-30 cm long. The oblong spikelets are sterile and are on short stalks. The spikelets are located in two rows on opposite sides of the stem axis. The plant appears very two-dimensional, and as fresh specimens they look almost as if pressed. The lemmas are awnless. Similar Species: X Festulolium braunii (K. Richt) A. Camus [Festuca pratensis X Lolium multiflorum]. This hybrid differs from X F. loliaceum in having awned lemmas, but it also has hairless auricles.
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Copyright © Royal
BC Museum |
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Habitat: Dry, open sites in the steppe and montane zones.
In the Columbia Basin region, Macoun's Wildrye occurs at Windermere.