filled swamps, or peatlands partly drained after flood- 

 ing, provide satisfactory conditions for white cedar 

 reproduction (Korstian and Brush 1931; Little 1950). 



3.2.3 Growth Rates 



Seedling s. Little (1950) determined that 

 early growth varies greatly with substrate and light 

 conditions, with first year increments ranging from 

 2.5 cm to as high as 25 cm. Thereafter, seedlings 

 may grow more than 0.3 m annually on favorable 

 sites. This results in 3 m saplings in 7 or 8 years in 

 the South, and in about 1 years in southern New Jer- 

 sey. On unfavorable substrate, growth in 15 years 

 may be only 1.2 m. 



Mature trees . Korstian and Brush (1931) 

 published extensive life table data for natural- and 

 field-grown cedars. In the single controlled study of 

 mature Atlantic white cedar growth rates published, 

 Goiet and Lowry (1987) observed that cedars in 

 Rhode Island swamps grow an average of 0.79-1 .79 

 mm/yr radially, primarily during March through 

 August (Figure 20). They found that yearly variations 

 in growth within individual cedar swamps may be re- 

 lated to water level variations, but this relationship dif- 

 fers markedly from wetland to wetland. They 



Month 

 Figure 20. Annual radial growth curves for Atlantic 

 white cedar in six Rhode Island swamps. Each point 

 represents the mean of three trees; each line repre- 

 sents one site (from Golet and Lowry 1987). 



observed no general relationship between water 

 regime and annual radial growth. Cedar growth 

 seemed more closely linked to ground water 

 chemistry and forest stand characteristics than to the 

 hydrological regime. 



Ve getative reproduction . In natural settings, 

 cedar sometimes develops lateral or basal shoots 

 after injury. Seedlings repeatedly browsed by deer 

 develop multiple stems through layering (Little 1950; 

 A. Laderman and J. Moore, unpubl. field notes). 

 However, layering stems appear to grow much more 

 slowly than the original growth, and, unlike often 

 vigorous hardwood sprouts, these stems never form 

 an important forest component (Little 1950). 



Almost from the time the species was first 

 described, it was known that Atlantic white cedar 

 propagates well from cuttings (letters of J. Bartram in 

 Darlington 1 857). The preparation of seedbed, seed, 

 and cuttings for propagation, as well as the influence 

 of competing vegetation on seedling success are dis- 

 cussed under management (Chapter 6). 



3.2.4 Maximum Size and Ag e 



The Atlantic white cedar reaches its maxi- 

 mum size in the southernmost part of its range. The 

 "champion" tree now living is in Escambia County, 

 Alabama, on a tributary of the Escambia River. It 

 measures 26.5 m tall and 150 cm dbh and is es- 

 timated to be ca. 268 years old (Hunt 1986 

 [measured in 1961]; Hartman 1982; J. Arany, pers. 

 comm. [measured in 1985]). Trees approaching the 

 Alabama champion in stature have been recently 

 reported in Florida (Wills and Simmons 1984; Ward 

 and Clewell, unpubl.). 



Clewell and Ward (1987) report that direct 

 counts of the annual rings of the largest trees have 

 not been possible, for increment tools fail to 

 penetrate properly, and no record-sized trees have 

 been recently cut. The largest trees in Mississippi 

 and Florida are possibly 150 to 190 years old as 

 extrapolated from the minimal data available on 

 growth rates. 



The maximum size of Chamaecyparis 

 decreases from its mid-range northward, e.g., the 

 maximum heights reported for North Carolina/Vir- 

 ginia were 36.6 m; for southern New Jersey 21 .3 m; 

 and for New Hampshire only 12.5 m. 



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