umphant seeds, from which a cluster of spruces 

 expanded and went out to meet the surrounding 

 advancing forest. Fighting deer sometimes cut 

 the sod and thus allow a few tree seeds to assert 

 themselves. Wind may blow down a tall tree 

 which lands in the edge of the park. Along its 

 full length grows a line of invading forest. Oc- 

 casionally the earth piled out by a gopher, or 

 by a coyote in digging out a gopher, offers an 

 opportunity that is seized by a tree seed. An 

 ant-hill in a meadow may afford a footing for 

 invading tree seeds. On one occasion a cliff 

 tumbled and a huge rock-fragment bounded 

 far into the sloping meadow. Trees sprang 

 up in each place where the rock tore the sod 

 and also around where it came to rest in the 

 grass. 



These breaks in the sod made by animals or 

 other agencies do not always give triumph to 

 the trees. Seedlings may eagerly start in these 

 openings, but, being isolated, they are in greater 

 danger, perhaps, than seedlings in the forest. 

 Rabbits may nibble them, woodchucks devour, 

 or insects overrun them. The surrounding grass 



236 



