Abstract
Levels of N, P, Ca, Mg, K, Al, Fe, Zn, Mn, and B were determined in foliage from tamarack (Larix laricina (DuRoi) K. Koch) in a bog, conifer swamp, and fen from budbreak to leaf abscission. Elongation of needles and lateral shoots as well as dry and ash weight of needles were determined. Expansion of needles and shoots ceased at similar dates for all sites, but trees in the fen had significantly longer needles and lateral shoots.On August 13, foliar concentrations of N, Ca,and Mg were higher in the fen than in the conifer swamp or bog, while concentrations of Al, Fe, Zn, Mn, and B were higher in the bog than the other two sites. Phosphorus concentrations in foliage were similar on this date in the fen and conifer swamp but were lower in the bog site. Despite significant between-site variation for certain foliar elements, two patterns of seasonal variation in nutrient concentrations were discerned. Significant between-site differences in the amounts and rates of needle and shoot elongation, foliar nutrient concentrations at a single sampling time, and patterns of certain foliar elements were associated with variations in nutrient status and moisture–aeration conditions of the study sites.
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