juvenile vascular leaf A vascular leaf that is distinct from adult leaves, being characterized by particular anatomical traits namely, wax and trichome distribution, presence or absence of epidermal cell types, cell wall shape and biochemistry. 維管束系幼葉 (Japanese, exact) PO_GIT:371 plant_anatomy PO:0006339 Many species have juvenile leaves at the base of the stem, adult leaves at the apex, and transition leaves in between. In maize, juvenile leaves are at the tip of the stalk (stem), which differentiates first, with adult leaves at the base, while other grasses may have other arrangements. The first juvenile leaves in Poaceae are the embryonic leaves found in the grass kernel (caryopsis). hoja juvenil (Spanish, exact) vascular leaf