Book  (1981)  Page(s) 277.  
 
R. californica ....'Ardens' (Späth). Flowers crimson-red, 6-7 cm./2.4-2.8 in. across, anthers golden-yellow. June. Originated before 1930 with L. Späth, Berlin, from seed.

Book  (1930)  Page(s) 405.  
 
californica ardens. Arb. Spaethian. Among the seedlings of the Californian Rose from Colorado-seeds, was found this beautiful form with 6 to 7 cm across, fiery crimson-coloured blooms, from which colour the golden-yellow stamens stand out effectfully. Blooming period is June.