Measurement of age and growth rate in the crustose saxicolous lichen Caloplaca trachyphylla using 14C accelerator mass spectrometry

Sections of the crustose saxicolous lichen, Caloplaca trachyphylla, were dared using C-14 accelerator mass spectrometry (AMS). The data show a strong linear dependence of radial position on time (r=0.993), suggesting a constant radial growth rate. This specimen had averaged a marginal growth rare of 1.48 mm/year. Extrapolation of the growth curve yields a thallus age of 20 years. These data demonstrate the feasibility of using AMS technology to precisely date lichen tissues and determine growth races of lichen thalli. (C) 2000 The British Lichen society.