This section is from the book "Handbook Of Hardy Trees, Shrubs, And Herbaceous Plants", by W. Botting Hemsley. Also available from Amazon: Handbook of hardy trees, shrubs, and herbaceous plants.
We merely mention Rosa berberidifolia, the Barberry- or Simple-leaved Rose to complete the series of Roses, for it is hardly known in our gardens. It is an undershrub 2 to 3 feet high, producing suckers abundantly, armed with prickles, and its simple leaves are obovate, denticulate, and destitute of stipules. The flowers are about the size of the Banksian, solitary, bright yellow, with a deep purple spot at the base of each petal. This curious species, by some botanists considered as forming the type of a distinct genus, under the name Hulthemia, or Lowea, is only found in the saline plains of the North of Persia and Soongaria, where it is so abundant that it is used for heating ovens. Its culture is difficult in the North, where it flowers without fruiting; but it would doubtless succeed better in the South, and probably some interesting varieties might be obtained, either directly or by crossing it with other species. In fact, one very curious hybrid exists already, known as Hardyi, the issue of a cross between R. clino-phylla and R. berberidifolia, the latter furnishing the pollen. This hybrid resembles its mother in its compound leaves and large stature, and its father in its ternate prickles, and especially in its yellow flowers, whose petals bear a brown spot at the base.