NATIVE WOODY PLANTS OF THE UNITED STATES 231 



Rhus radicans, see Rlius toxicodendron. 

 Ehus rydbergii, see Rhus toxicodendron. 

 Ehus sambucina, see Rhus glabra. 

 Ehus sandbergii, see Rhus glabra. 

 Ehus tesselata, see Rhus glabra. 



Ehus toxicodendron L. Poison-ivy 



R. desertorum Lunell, R. eximia Standl., R. longipes Greene, R. microcarpa 

 Steud., R. radicans L., R. rydbergii Small, R. toxwodendron radicans 

 Dippel, Toxicodendron radicans (L.) Kuntze, T. biternatum Greene, T. 

 eximium Greene, T. fothergilloides Lunell, T. hesperinum Greene, T. 

 macrocarpum Greene, T. negundo Greene, T. punctatum Greene, T. rufes- 

 cens Greene, T. rydbergii (Small) Greene. 



Range: 2, 6, 7, 8, 9, 11, 12, 13, 15, 16, 17, 18, 19, 20, 21, 22, 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 to a vigorous, high-climbing vine. This species 

 has been much broken up as the synpnomy 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. 



Ehus trilobata Nutt. (pi. 34, B). Lemonade sumac. 



R. canadensis trilobata (Nutt.) Gray, R. crenatifolia Schlecht., R. emoryi 

 Woot., R. osterhoutU Rydb., R. oxyacanthoides (Greene) Rydb., R. tri- 

 lobata mollis Greene, R. utahensis Good., Schmaltzia trttobata, (Nutt.) 

 Small, S. afflnis Greene, 8. anisophylla Greene, S. bakeri Greene, S. 

 cognata Greene, 8. cruciata Greene, 8. emoryi Greene, 8. glabrata Greene, 

 8. glauca Greene, S. glomerata Greene, 8. leiocarpa Greene, S. malaco- 

 phylla Greene, S. oxyacanthoides Greene, 8. pulchella Greene, 8. quercir 

 folia Oreene, S. ribifolia Greene, 8. scaberula Greene, 8. simplicifolia 

 Greene, S. straminea. Greene, S. subpinnata Greene. 



Range: 1, 3, 4, 5, 8, 9, 10, 11, 12, 13, 14, 15, 16, 19, 20, 22, 24, 25. 

 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 1 so in Utah. 



Ehus typhina Tomer (pi. 36, A). Staghorn sumac. 



R. hirta (L.) Sudw., Datisca hirta L., Schmaltzia 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. pulvinata. Greene. 



