Figure 18. A remarkable example of multiple-trunked stooling of Ogeechee tupelo at 

 Sutton's Lake (Apalachicola River, FL). This slough floods to depths of 4.2 m (14 ft); 

 cypress knees may exceed 3.7 m (12 ft) in height. 



weather patterns, watershed size and mor- 

 phology, floodplain size and topographic 

 variation, and drainage rates of flood- 

 plain soils. The effects of flooding are 

 most critical during the growing season, 

 particularly during the period of leaf- 

 out. Floods during the dormant season 

 have relatively little effect on the 

 physiology and survival of bottomland spe- 

 cies (Hall and Smith 1955), other than 

 possible damage due to mechanical abrasion 

 or breakage. 



Flood depth is critical in at least 

 three ways. First, stem lenticels (pores) 

 may be blocked. These structures are 

 important in some species in both root 



aeration (Armstrong 1968; Chirkova 1968) 

 and the release of volatile end-products 

 of anaerobic respiration, such as ethanol , 

 ethylene, and acetaldehyde (Chirkova and 

 Gutman 1972). Floodwaters deep enough to 

 inundate major portions of the stem lenti- 

 cels thus cause reduced oxygen supply to 

 the roots and toxic accumulation of the 

 anaerobic respiratory products. The second 

 effect of flood depth is the reduced rate 

 of oxygen diffusion through the water 

 column to the roots with increasing flood 

 depth. Finally, seedlings submerged by 

 the water column may undergo severe mor- 

 tality through anoxia, mechanical damage, 

 and siltation. 



34 



