are most common within spikerush/ 

 beak rush flats suggesting that only 

 there are they likely to escape 

 destruction by fire. Coco plum is 

 also very cold sensitive. The domi- 

 nant species typically accounts for 

 70% to 80% of the canopy composition 

 and over 80% of the density. Fre- 

 quently, several large multi-branch- 

 ed coco plum plants constitute most 

 of the vegetational cover. This is 

 because of their sprawling growth 

 habit in which many lateral branches 

 are produced parallel to the ground. 

 These laterals consolidate outward 

 along the periphery of the tree is- 

 land and give the visual impression 

 of a rank growth of many individual 

 plants. The height of the vegeta- 

 tion in coco plum thickets ranges 

 from 2.5 to 6 m (8 to 20 ft). 



Coco plum thickets are variable 

 both in terms of structural geometry 

 and floristic composition. On the 

 average, these thickets possess a 

 circular or ovate outline, but fre- 

 quently are elliptical where surface 

 drainage gradients are steep. Al- 

 though coco plum is the community 

 dominant, several other species are 

 typically present, and epiphytes are 

 located in the densely shaded under- 

 story where surface fire has been 

 absent for several decades. Among 

 the species commonly associated with 

 coco plum are: cypress ( Taxodium 

 distichum ) , red bay ( Persea borbo - 

 nia ) , sweet bay ( Magnolia virqin - 

 iana ) , pond apple ( Annona glabra ), 

 swamp fern ( Blechnum serrulatum ), 

 myrsine ( Myrsine quianensis ), giant 

 wild pine ( Tillandsia utriculata ), 

 stiff-leaved wild pine ( Tillandsia 

 fasciculata ) , reflexed wild pine 

 ( Tillandsia balbisiana ), and creep- 

 ing orchid ( Habeneria nivea ). 



Willow/pond apple/wax myrtle 

 thickets are very common in middle 

 and eastern Shark River Slough. 

 They are characterized by a very 



dense and consolidated growth of 

 willow ( Salix ) , pond apple ( Annona 

 glabra ) , and wax myrtle ( Myrica 

 cerifera ) , ranging in height from 

 1.5 to 5 m (5 to 16 ft). This 

 community develops most frequently 

 along the margins and elongated 

 tails of the broad-leaved tree 

 island in the central Shark Slough. 

 In the local vernacular, they are 

 referred to as "hell-holes" or 

 "hell-nests", terms which aptly 

 describe their impenetrability. An 

 important successional relationship 

 appears to be one going from willow 

 thickets to willow/pond apple/wax 

 myrtle thickets to coco plum and 

 then to bayhead forests. The wil- 

 low/pond apple/wax myrtle formation 

 also appears to develop on a bay- 

 head-dominated site following a very 

 severe fire or series of fires that 

 destroy several centimeters of 

 organic soil, thereby reducing the 

 relative elevation of the site. 

 This same shift from the bayhead 

 community to the present one prob- 

 ably results from an increase in the 

 duration of the hydroperiod at the 

 site as well. 



Many vertebrate species utilize 

 the willow/pond apple/wax myrtle 

 community as a feeding or nesting 

 habitat. Notable among these are 

 the whitetailed deer, the bobcat, 

 the Florida indigo snake, the black 

 racer snake, the phoebe, the yellow- 

 billed cockoo, and the alligator. 



Pond apple/willow thickets 

 develop in and around open ponds 

 that typically contain some surface 

 water all year. The soils associ- 

 ated with the pond apple/willow 

 forest community are deep, often 

 well decomposed peats (i.e., muck). 

 These forests are very limited in 

 area, being usually associated with 

 hardwood hammocks, and particularly 

 with Indian midden sites. 



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