VARIATION IN VESSEL LENGTH AND DIAMETER IN STEMS OF SIX TROPICAL AND SUBTROPICAL LIANAS

Within-species and within-stem variation in vessel diameter and total vessel length were examined using the latex paint method on six species of tropical and subtropical lianas (woody vines). Narrow vessels were almost always rather short, but wide vessels ranged from short to long. Within Pithecoctenium crucigerum, larger diameter stems tended to have longer as well as wider vessels, with a maximum vessel length and width of 6.25 m and 366 μm, respectively. Within stems of Saritaea magnifica, P. crucigerum, Hippocratea volubilis, and Vitis rotundifolia, narrow vessels had lower mean, median, and maximum vessel lengths than wide vessels. Vessels with intermediate diameters tended to have intermediate lengths. In Stigmaphyllon ellipticum and Bauhinia fassoglensis the outer system of secondary xylem tended to have longer as well as wider vessels than the inner system. Those narrow vessels (<50 μm) that did occur in the outer system were short (<0.20 m), and were similar in length and diameter to those of the inner system.