Micromorphology of Pine Needle Primordia and Young Needles after Bud Dormancy Breaking.

Using a scanning electron microscope, the micromorphologies of needle primordia and the young needles of seven pine species (, , , , , , and ) were analyzed at phenological stages B2 and B3 (according to Debazac). In B2, needle tips were rounded or pointed, depending on the species. In and , teeth were noted on the tips.

Stomatal density in Pinus sylvestris as an indicator of temperature rather than CO : Evidence from a pan-European transect.

The commonly observed negative relationship between stomatal density (SD) and atmospheric CO has led to SD being proposed as an indicator of atmospheric CO concentration. The use of SD as a proxy for CO , however, has been hampered by an insufficient understanding of the intraspecific variation of this trait. We hypothesized that SD in Pinus sylvestris, a widely distributed conifer, varies geographically and that this variation is determined by major climatic variables.