Lichen Pendants for Transplant and Growth Experiments

Abstract

Lichens were cultured by attaching a thallus fragment to a nylon monofilament loop with silicone sealer. Two effective methods for adjusting lichen mass to a standard moisture content were developed (the ‘reference-sample’ and ‘sacrificial’ methods). These corrections for moisture content allow detection of very small changes in dry mass without having to oven dry (and kill) all transplants. Average annual biomass growth rates for non-fragmenting species were typically between 5 and 30%. Annual biomass growth rates of healthy, vigorous individuals, as indicated by the 75th percentile, were mostly between 10 and 40%. Alectoria sarmentosa was prone to fragmentation despite the maintenance of healthy thalli. The other species can be ranked by biomass growth rates as follows: Evernia prunastri> Lobaria pulmonaria=Usnea longissima> Pseudocyphellaria rainierensis=Lobaria oregano.