PLANT COMMUNITIES OF SANDY SOIL 325 



Ranunculaceae, crowfoot family 



Pulsatilla ludoviciana; in sandy soil with some humus, or on disintegrated granites. 

 Only occasional. 



Fumariaceae, fumitory family 

 Capnoides aureum; along roads and trails in disintegrated granite. 



Brassicaceae, mustard family 



Cheirinia wheeleri; in coarse sand and disintegrated granite. 



*Lepidium densiflorum; chiefly in fine-grained sand. 



Sophia incisa; along roadsides, a plant of "weedy" tendencies. 



Cappararidaceae, caper family 

 *Peritoma serrulatum; this well known "bee plant" usually in fine-grained sand. 



Grossulariaceae, gooseberry family 



Grossularia inermis; in moister areas along beds of intermittent streams. 

 *Ribes inebrians; common shrub in sand or disintegrated granite among rocks. 



Rosaceae, rose family 



*Cercocarpus montanus; found only as scattered individuals, never forming pure 



stand as at the mountain front in northern Colorado. 

 Dasiphora fruticosa; only where there is some accumulation of humus. 

 *()reobatus deliciosus; chiefly among rocks and in disintegrated granite without 



much sand. 

 *Potentilla concinna; belonging to highly primitive growths in coarse sand. 

 *Potentilla hippiana; represented in almost all soils of the area. 

 Primus melanocarpa; in moister parts of draws, especially where there is some 



humus. 

 Rosa bourgeauiana; occasional in moister areas with some humus. 

 *Sericotheca dumosa; chiefly among rocks and in disintegrated granite without 



much sand. 



Fabaceae, pulse family 

 Lupinus argenteus; on sandy rock-wash fans. 



Geraniaceae, geranium family 

 Geranium parryi; sparingly present on most soils. 



Euphorbiaceae, spurge family 



Chamaecyce serpyllifolia; only on sand. 

 *Tithymalus robustus; typically on sand. 



Anacardiaceae, cashew family 



*Rhus trilobata; the well-known "skunk bush" of the mountain front found here 

 on loose sand as well as on stable soils. 



t m 





