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YELLOW POPLAR ix TENNESSEE. 



is feeble when compared with that of many other broad-leaf species with 

 which it is associated, particularly with that of chestnut, because after a 

 small poplar has been killed down by fire a few times, the root generally 

 dies. Old trees of yellow poplar are protected by their thick bark, and 

 are rarely killed outright. However, many old trees on dry sites have 

 butt hollows, which open on their upper side and which resulted from fire. 



FIG 2. A group of yellow poplars which are growing on a rocky slope and 

 which have been injured at the butts by fire. Note the hollow on the left of 

 the base .of the large tree and the scar to the right of the hollow, both caused 

 by fire. 



Other injurious agencies. The tender shoots and leaves of small yel- 

 low poplars are freely eaten by cattle and sheep. For this reason stock 

 should not be grazed on areas which are in process of stocking until the 

 small trees become 8 to 10 feet in height. Hogs do not eat yellow poplar 

 roots. They dig up seedlings, however, while rooting for other food on 



