The absence of larch budmoth outbreaks and subsequent consequences on tree rings together with a distinct climate–growth relationship enhance the dendroclimatic potential of larch ring width data from the Tatra Mountains. Regular population oscillations are generally considered to arise from trophic interactions, though it is unclear how such cycles are affected by biotic and abiotic factors. Cyclic outbreaks of the larch budmoth (LBM; Zeiraphera diniana
), perhaps the most prominent example of periodic insect population dynamics, leave distinct "fingerprints" in the annual rings of host trees, and have been reconstructed over 1,200 years in the European Alps. Although LBM individuals are known to exist in other regions, it is unclear whether recurrent mass outbreaks historically occurred elsewhere. Here, we present new larch (Larix decidua
) host and pine (Pinus cembra
) non-host chronologies from the Slovakian Tatra that comprise 323 ring width samples dating back to 1612 AD. May-June and May-July temperatures control larch and pine growth (r1951-2011
= 0.63 and 0.57; p<0.001), respectively. LBM outbreak-induced defoliation patterns and subsequent ring width reductions were absent over the past three centuries, during which larch (host) and pine (non-host) growth was significantly synchronized (r1725-2012
= 0.48; p<0.001). Spatially limited host forests of overall low stand densities along the northwestern Carpathian arc together with a relatively warm climate envelope are most likely responsible for the absence of cyclic LBM outbreaks. Tree-ring chronologies from these ecotones, free of pulsed disruptions, therefore, represent unique paleoclimatic archives ideal for reconstructing interannual to multi-centennial variations in Eastern European summer temperature.
Konter, Oliver; Esper, Jan; Liebhold, Andrew; Kyncl, Tomas; Schneider, Lea; D thorn, Elisabeth; Buntgen, Ulf. 2015. Tree-ring evidence for the historical absence of cyclic larch budmoth outbreaks in the Tatra Mountains. Trees. 29(3): 809-814.