3. Rosa blanda, Ait. var. Arkansana, (Porter). Although frequently observed before, it was first described by Dr. Porter as Rosa Arkansana* from specimens collected on the banks of the Arkansas River [Colorado] by Mr. Brandagee. The original specimen, in flower, is in the herbarium of Lafayette College. Bush apparently low, I to 2 feet high; stem, foliage and fruiting receptacles glaucous; flowers corymbose; sepals entire; bracts lanceolate; leaflets 7 to 11, mostly 9, oblong-elliptical to oblanceolate, somewhat cuneate at base; stipules rather broad; stem prickly. Bulletin of the Torrey Botanical Club 17(6): 141-149 (June 9, 1890) Remarks on the Group Cinnamomeae of the North American Roses G. N. BEST
The stipules are as often broad as narrow; the outer sepals are rarely lobed, probably not much more frequently than in R. blanda, from which it is distinguished by its habit of growth, its glaucousness, by one or two pairs more of leaflets, its prickly stem and by its being more or less glandular. It would therefore appear that the characters relied upon to differentiate it from the type lack specific distinctness.
Var. Arkansana ranges from Texas and New Mexico northward to British America and westward to the Rockies and probably beyond. It undergoes many modifications. On dry prairies it becomes markedly surculose; its rhizomes are transformed into in-ground stems which give off annual shoots like flowering branches. Since these rhizomes have no leaves, the demand for more foliage is met by an extra pair of leaflets on the suckers. In protected locations, as margins of woods and thickets, it attains a height of from three to five feet, with stem either smooth or prickly, and lives for years. It is sometimes found densely resinous. Like R. blanda, rudimentary glands on the sepals and stipules and under surfaces of the leaflets are rarely absent. When its flowers are solitary, as sometimes happens, the low prickly forms bear some resemblance to Rosa acicularis, from which it is readily distinguished by its glaucous stem and foliage, leaflets more numerous and of another shape.
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