46 



TREES AND FLOWERS OF 



(yellow) 



(pink) 



EVENING PRIMROSE 



ROCK ROSE 



Evening Primrose (Onagra). The evening prim- 

 rose is fairly frequent along the roadsides, particu- 

 larly at the lower elevations, in well-drained, moderate- 

 ly dry soils. The plant is usually between one and two 

 feet high, with stout, tough, branching stems. The 

 leaves are lance-shaped, on short stalks. The bright 

 yellow flowers are distributed along the stem among 

 the leaves; they have four broad-ended petals and are 

 somewhat longer-stalked than are the leaves. Blos- 

 soming lasts from early July until about mid-August. 

 The seed-pods are long and slender and split in four 

 directions when they are ripe. 



Rock Rose (Pachylophus) . The rock rose be- 

 longs to the evening primrose family. It is found only 

 in very dry soils, generally gravel banks, below the 

 6,000 foot level. There is a basal rosette of leaves, 

 lance-shaped in general outline, with slightly irregular, 

 wavy margins. From the midst of these rise several 

 short-stemmed flowers, three inches or a little less in 

 diameter, of a beautiful rose color. The season for 

 rock roses is soon over, lasting only until early in 

 July, but sometimes after the early fall rains a second 

 crop of flowers will appear. 



