The ultrastructure of intercellular passageways in vessels of yellow poplar (Liriodendron tulipifera,L.) part I: Vessel pitting

Summary The newly matured intervessel pit membranes of yellow poplar contain distinct openings. With increasing age the membranes become progressively occluded with incrustations which obstruct the small openings. Openings were not detected in the vessel-to-ray parenchyma and vessel-to-fiber pit membranes at any age.Paper No. 3478 of the Journal Series of the N. C. State University Agricultural Experiment Station, Raleigh, N. C.