Rangewide provenance variation in Atlantic white-cedar (Chamaecyparis thyoides ): Early survival and growth in New Jersey and North Carolina plantations

Journal Article

Transfer Guideline: Recommendation

Atlantic white-cedar, Chamaecyparis thyoides (L.) B.S.P., is an important wetland tree species occurring along the Atlantic coast of the United States, from Maine to Florida, and westward along the Gulf of Mexico coast to Mississippi.Within this range, its distribution is patchy and disjunct, due to the scattered occurrence of suitable wetland habitat, natural range disjunctions and historic declines. Much recent interest has focused on the species, its management and its restoration, but very little is known about its geographic pattern of phenotypic variation. This study presents second year results from the first rangewide white-cedar provenance test. Rooted cuttings were propagated from 34 source populations, encompassing the entire latitudinal range (298120–448200N) of the species, and planted in three common garden plantations, two in New Jersey and one in North Carolina. Survival was generally high for Atlantic coastal populations at all three planting locations, ranging from 72% to 100% for individual provenances, but many Florida and Gulf coast populations exhibited reduced survival and winter hardiness in New Jersey, with 44–94% survival and 11–67% of surviving trees experiencing winter dieback. Height growth varied significantly between planting sites and provenances, and a significant site by provenance interaction suggested that relative performance of provenances varied across sites. All populations grew significantly more at Hofmann Forest, North Carolina than at the two New Jersey plantations, with mean 2-year height growth ranging from 54 to 96 cm for individual provenances at this site. By comparison, mean height growth ranged from 23 to 63 cm at Richard Stockton College, and from 12 to 32 cm at Brendan T. Byrne State Forest, New Jersey. Within individual sites, we identified polynomial relationships between height growth and latitude of origin, with southern Atlantic coastal populations among the best performers at all sites. Patterns of growth phenology were significantly correlated with latitude of origin. Spring growth rate and the percent of total growth occurring during spring were positively correlated with latitude, while fall growth rate and the percent of growth occurring during fall were negatively correlated with latitude. These early results suggest that significant provenance variation exists among white-cedar populations, and that local sources should be preferred for regeneration and restoration purposes.