There are at least 100 species of roses (Rosa) in the world. All are native to the Northern Hemisphere, and more than 50 rose species can be found growing in the Arboretum’s Bradley Rosaceous Collection. Centuries of hybridizing within and between species has resulted in thousands of cultivated varieties, with more being introduced every year. Though species roses (most of which bloom just once per year) are not as popular as perpetual-blooming hybrid cultivars, they can definitely add to garden landscapes. This Donald Wyman article and another one in Arnoldia provide details on a number of rose species.
– Nancy Rose, editor of Arnoldia