Published online by Cambridge University Press: 31 May 2012
Internal cone temperatures recorded in the mornings and in the afternoons demonstrated marked differences between sunny and shaded sites. Analysis of variance confirmed differences between treatment as highly significant. High and low cone temperatures coincided with high and low ground temperatures. The average correlation coefficient relating cone and ground temperatures was highly significant, while that for cone temperatures and cone size was non-significant.
Heavy insect mortality occurred in cones exposed to direct solar radiation but mortality remained relatively low in the cones left in the shade. The greatest high-temperature mortality occurred during summer between late June and early August.