NATIVE WOODY PLANTS OF THE UNITED STATES 231 
Rhus radicans, see Rhus toxvicodendron. 
Rhus rydbergii, see Rhus toxicodendron. 
Rhus sambucina, see Rhus giabra. 
Rhus sandbergii, see Rhus glabra. 
Rhus tesselata, see Rhus glabra. 
Rhus toxicodendron L. Poison-ivy 
R. desertorum Lunell, Rk. eximia Standl., R. longipes Greene, R. microcarpa 
Steud., R. radicans L., R. rydbergit Small, R. toxicodendron radicans 
Dippel, Toxicodendron radicans (L.) Kuntze, T. biternatum Greene, T. 
eximium Greene, 7’. fothergilloides Lunell, T. hesperinum Greene, T. 
macrocarpum Greene, T. negundo Greene, T. punciatum Greene, T. rufes- 
cens Greene, T. rydbergii (Small) Greene. 
RABEL Otomo o lon oO Gum IS TO D0) 20 2) 23.) 24: 
25, 27, 28, 29, 30. 
Site: Dry, well-drained, sun, shade. 
Fruit: Drupe, available September—November. 
A small to large poisonous shrub or vine; very variable in habit, from a 
small, nearly herbaceous shrub te a vigorous, high-climbing vine. This species 
has been much broken up as the synonomy indicates, but good botanical char- 
acters Separating the forms as species do not appear to be satisfactory. A 
study of the forms in Indiana by Dream (162) showed that the low, erect 
forms are branches of underground stems; that the thick-leaved forms are 
always found in places exposed to heavy winds and direct sunlight; and that 
the hairy-fruited forms are rare, distributed throughout the area, and without 
other characters to distinguish them. 
Stomach records: Sixty species of birds including ruffed grouse, bobwhite, 
wild turkey, sharp-tailed grouse, ring-necked pheasant, and greater prairie 
chicken; composed 0.8 percent of fall food of prairie chicken in Wisconsin. 
Observations: Nineteen species of birds including ring-necked pheasant; white- 
tailed deer; leaves refused by captive marsh rabbits. 
Rhus trilobata Nutt. (pl. 34, B). Lemonade sumac. 
R. canadensis trilobata (Nutt.) Gray, R. crenatifolia Schlecht., R. emoryi 
Woot., R. osterhoutui Rydb., R. oxyacanthoides (Greene) Rydb., R. tri- 
lobata mollis Greene, R. utahensis Good., Schmalizia trilobata (Nutt.) 
Small, §. ajffinis Greene, S. anisophylla Greene, 8. bakeri Greene, 8. 
cognata Greene, S. cruciata Greene, S. emoryi Greene, S. glabrata Greene, 
S. glauca Greene, S. glomerata Greene, S. leiocarpa Greene, S. malaco- 
phylla. Greene, S. oxyacanihoides Greene, S. pulcheila Greene, S. querci- 
folia Greene, 8S. ribifolia Greene, S. scaberula Greene, S. simplicifolia 
Greene, S. straminea Greene, S. subpinnata Greene. 
Rangel (3,45.0)o,. 9; 10, 1 12 ts T4015, 16, 19. 20,22... 24.7,.95. 
Site: Dry, well-drained, sun, shade. 
Fruit: Drupe, available the year round. 
A small shrub; roots very long; sometimes thicket forming; under natural 
conditions endures extreme drought; 10,000-25,0000 seeds per pound. This 
species has been much broken up, and the segregates recombined as the syn- 
onomy indicates. 
Stomach records: Nineteen species of birds, including ruffed grouse, bobwhite, 
valley, Gambel and western quail, greater prairie chicken and lesser prairie 
chicken. Observations: Ring-neck pheasant, sage hen, scaled quail; moun- 
tain sheep; of slight importance as browse for mule deer. Worthless to good 
forage for stock; of most value in Arizona and Colorado, less so in Utah. 
Rhus typhina Torner (pl. 36, A). Staghorn sumac. 
Rf. hirta (L.) Sudw., Datisca hirta L., Schmalizia hirta (L.) Small. 
Range: 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28. 
Site: Dry, well-drained, sun, shade. 
Fruit: Drupe; available in September, persistent the year round. 
A large shrub to small tree; sprouts persistently from the roots after cutting 
or injury; forms loose thickets; 50,000 seeds per pound. 
A plant more or less intermediate between this and R. glabra has been de. 
scribed as R. pulwinata Greene. 
