52 Muhlenbergia, Volume 9 
LACTUCA VIROSA L. 
Rare on the flood plains of Bear creek; (Washabaugh 
county). Z. zwtegrata (Gren. & Godr.) A. Nelson. 
RATIBIDA COLUMNARIS PULCHERRIMA (DC.) D. Don. Red cone 
flower. 
Occasional on the plains; (Washabaugh county). 
RUDBECKIA FLAVA Moore. Prairie black-eyed Susan. 
Very abundant everywhere on the uplands; (Bennett county) 
SENECIO RIDDELLU T. & G. 
Abundant along old roads. 
SOLIDAGO MOLLIS Bartl. Prairie goldenrod. 
Abundant on the plains; (Bennett county). 
SOLIDAGO PITCHERI Nutt. 
Rare in woodlands; (Washington county). 
SOLIDAGO TRINERVATA Greene 
Rare on flats along streams; (Washabaugh county). 
TARAXACUM ERYTHROSPERMUM Andrz. Red seeded 
dandelion. 
Rare along Wounded Knee creek; (Shannon county). 
TOWNSENDIA GRANDIFLORA Nutt... Bad land blue aster. 
Characteristic and abundant on loose clay of bad land 
slopes. (Washington county). 
State University, Vermillion, South Dakota. 
THE OAKS OF THE PACIFIC SLOPE—II 
By A. A. HELLER 
THE BLUE OAK 
QUERCUS DouGLAsit H. & A. Bot. Beech. 391. 1841. 
This oak, a hill species, is readily recognized by the char- 
acteristic blue-green color of its foliage. At maturity it is a 
tree 20 to 50 feet high, with a well rounded crown and short 
trunk 1 to 2 feet in diameter. ‘Trees growing under very favor- 
