BARTRAM: BOTANIZING IN SOUTHERN ARIZONA 243 
PoPuLus —— (S. Wats.) Sarg. Catkins fully developed and 
falling a late January. 
RCUS ARIZONICA Sarg. Scattered along the creek near the mouth 
of Sabino Can 
QUERCUS eae Torr. With the preceding but more abundant and 
larger 
QUERCUS HYPOLEUCA Engelm. Sterile but easily recognized by the 
leathery leaves densely white woolly beneath. 
QUERCUS OBLONGIFOLIA Torr. This and the preceding species of oaks 
are all confined to the lower end of Sabino Canyon, where they seem to exist 
as waifs carried down by the stream from higher levels in the region about 
Mt. Lemmon 
CELTIS PALLIDA Torr. Frequent along arroyos in the Tucson Mountains. 
PARIETARIA OBTUSA Rydb. Localized on a shaded ledge near Picture 
Rocks. 
PHORADENDRON MACROPHYLLUM (Engelm.) Cockerell. Abundant on 
Populus in the plains and foothill 
PHORADENDRON CALIFORNICUM ee The abundant small red berries 
and bare stems make a very attractive combination. Chiefly on Mesquite in 
the plains 
ERIOGONUM POLYCLADON Benth. Recognizable but long past flowering. 
ERIOGONUM PINETORUM Greene. Long past flowering but leaves and 
fruit ere enough for identification 
Erioconum Wricuti Torr. Widely distributed over arid rocky 
slopes a “he foothills. 
RUMEX HYMENOSEPALUS Torr. Common in sandy areas throughout 
the — 
PoL UM PUNCTATUM Ell. Edge of stream in the foothills of the 
Santa Caidting ntain 
ATRIPLEX CANESCENS ee. Nutt. Several forms of this species 
are abundantly over the plains 
ATRIPLEX ROSEA L. Young plants in the sandy bed of an arroyo near 
Picture Rocks. 
CHENOPODIUM PAGANUM Reichenb. Sparingly introduced in waste places. 
AMARANTHUS PANICULATUS L. A common weed of fields and waste 
places. 
WEDELIELLA INCARNATA (L.) Cockerell. Flowering sparingly in sunny 
talus slopes in the foothills. 
HESPERONIA RETRORSA (Heller) Standl. Dry slopes near Picture Rocks. 
COMMICARPUS SCANDENS (L.) Standl. Localized in rock clefts along 
an arroyo west of Tucson. 
ANEMONE SPHENOPHYLLA Poepp. Frequent among rocks along arroyos 
in the foothills In full flower by mid-January. 
