172 



ECOLOGY 



30. White clover 



31. Red clover 



32. Locust . , 



33. Wistaria . 



34. Vetch . . 



35. Pea . . . 

 86, Bean . . 

 37. Groundnat 



V 



Trifolium repens .... . . Knuth 



Trifolium pratense . Knuth 



Eobinia Pseudacacia Gray 



Wistaria sinensis . Gray 



Vicia Cracea Knuth 



Pisum sativum Knuth 



Phaseolus vulgaris .... . . Gray 



Apios tuberosa Gray 



38. Partridge berry . 



39. Primrose . . . 



40. Loosestrife . , 



VI 

 Mitchella repens . . .... Gray 



Primula grandijlora, P. officinalis . Lubbock 

 Lythrum Salicaria Gray 



41. Milkweed . 



VII 



Asclepias Syriaca 



Knuth, Newell 



42. Lady's slipper 



VIII 

 Cypripedium acaule Newell 



HOW PLANTS AEE SGATTEEED AND PROPAGATED 



150. Field study of vegetative propagation. 



A. Collect, by digging them up, sketch, and describe any underground 

 stems of use in multiplying plants. There are many rootstock-produ- 

 cing species, such as June grass, quick grass, Bermuda grass, Canada 

 thistle, common sorrel (Rumex Acetosella), wild iris, wild ginger, sweet 

 flag, various sunflowers, and some mints. If possible dig away the 

 earth from one side of a hill of potatoes, and sketch some of the roots, 

 subterranean branches, and tubers. Bulbs are borne by a large pro- 

 portion of the members of the lily family. 



B. Make sketches to illustrate the spread of plants by rooting branches, 

 as in the raspberry, strawberry, and cinquefoils. 



C. In any cleared or partially cleared bit of woodland note the way in 

 which some trees produce a crop of sprouts from the stump. 



D. Examine the neighborhood of black locust trees (Eobinia), silver- 

 leaved poplars, or balm of Gilead poplars, to find out how far these 

 trees "spread by the root." Dig up a young sprout, with a piece of 

 the parent root, and sketch it. 



Refeeence. Beal, 63. 



