The effect of dwarf mistletoe on starch concentrations in the twigs and needles of lodgepole pine

Abstract

The effect of Arceuthobiumamericanum on starch concentrations in the needles and twigs of Pinuscontorta was analyzed at two study sites. We found that the starch concentration of needles from systemically infected branches was significantly higher than that of those from locally infected branches and that the concentration in needles from locally infected branches was significantly higher than that of those from uninfected branches. We also found that the starch concentration of twigs from locally infected branches was significantly higher than that of twigs from uninfected branches. Our results collectively suggest a trend in starch concentrations form 1% of dry mass or less in needles from uninfected branches to 1–2% in needles from branches with local infections to greater than 2% in needles from systemically infected branches.