Shrubs Of The Great Basin: A Natural History

Snowberry

Snowberry Symphoricarpos spp. THE SNOWBERRIES closely resemble their relatives, the twinberries. Like the twinberries, they may have their flowers borne in pairs. However, there is one easy way to distinguish them: twinberries always have red or black berries, while the snowberries have only white berries. When in flower, they can be separated by the fact that snowberries consistently have radially sym, metric or regular flowers; that is, the petals are all the same size and shape. Twinberry flowers, on the other hand, always show some irregularity or bi, lateral symmetry, like that of the honeysuckles. Both genera have two leaves borne at each node, but the snowberry has smaller leaves, generally between 1 and 3 centimeters long, although sometimes on sterile shoots in the shade they may be somewhat larger. Four species of Symphoricarpos occur commonly throughout the Great Basin. They are not always easy to separate from one another, and a few experts have shifted them back and forth between various names over the years. John Kartesz, as a result of his labors over the flora of Nevada, con, siders that our commonest species is S. areophilus, the mountain snowberry, which is found in two forms, a smooth and a pubescent variety. This is an erect shrub which may get as tall as 1.5 meters, though it is generally much less. The tubular flowers, produced from spring until the end ofsummer, are about 7 to 9 millimeters long and cream'colored to pinkish in this species. A similar species, which tends to be a lower, spreading form, is Parish's snowberry, S. parishii, which has somewhat smaller flowers 6 to 7 millimeters long. Both snowberries reproduce abundantly by vegetative means-the mountain snowberry develops many underground runners, while the pro, cumbent branches of Parish's snowberry root easily at the tips. Both shrubs inhabit dry, rocky slopes and ridges from around 4,000 to 11,000 feet. 251 Snowberry SNOWBERRY 253 Another low form with arching branches that root at the tips is S. acutus, the creeping snowberry, which resembles Parish's except that its flowers are smaller, only 3 to 5 millimeters long, and bell-shaped rather than tubular. In addition, the creeping snowberry has densely pubescent leaves, while those of Parish's are only sparsely pubescent. Within the Great Basin, the creeping snowberry has been found as far east as Elko and White Pine counties in Nevada as well as south, outside our area, in Clark County, Nevada. A species which occupies even drier sites on our desert mountain ranges is the desert snowberry, S. longiflorus. As the Latin name implies, it has longer flowers, some 10 to 15 millimeters long. These flowers are also characterized by an upper portion which flares out at an angle to produce a flower with a wider diameter than those of the previous three species. Tubular flowers which have an upper portion flaring out in this fashion at some angle to the long axis of the flower are described as being salverform; the word comes from the Latin salvare, which means tray. A phlox flower is a good example of this salverform type, since its upper portion resembles a tray with five scallops around the edge. Tubular flowers restrict the kinds of pollinators that can effectively visit a flower, and salverform types present a larger visible target for the insect as well as a landing platform, while the tubular basal portion insures that only the right pollinators will be rewarded. Unfortunately , all these species have somewhat similar oval leaves and are difficult to identify if only vegetative branches are available. The fruits mature in the form of white, round or oval berries 5 to 8 millimeters long, each enclosing two nutlets. Because of the fruits' waxy appearance , another common name for snowberries is waxberry, and they have also been called Indian currants and wolfberries. On many of our Great Basin ranges, the snowberry is a dominant shrub over large areas-it is fair to say that it is as characteristic of the mountain brush habitat as is big sagebrush in sagebrush-grass zones or shadscale in the salt deserts. Because of its abundance, it is an important browse plant for sheep. Even cattle and horses will eat it, although cattlemen will tell you that it is only a fair to poor plant for this purpose. Its value to deer is apparently about the same. Like the elderberries and...