Search results
Results from the WOW.Com Content Network
A leaf ( pl.: leaves) is a principal appendage of the stem of a vascular plant, [ 1] usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", [ 2][ 3] while the leaves, stem, flower, and fruit collectively form the shoot system. [ 4]
Phyllotaxis. Crisscrossing spirals of Aloe polyphylla. In botany, phyllotaxis (from Ancient Greek φύλλον (phúllon) 'leaf' and τάξις (táxis) 'arrangement') [ 1] or phyllotaxy is the arrangement of leaves on a plant stem. Phyllotactic spirals form a distinctive class of patterns in nature .
leaf base. Triangular, wedge-shaped, stem attaches to point. cuneiform. whole leaf. Narrowly triangular, widest on the opposite end from the stem, with the corners at that end rounded. cuspidate. cuspidatus. leaf tip. With a sharp, elongated, rigid tip; tipped with a cusp.
In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, including only woody plants with secondary growth, plants that are usable as lumber or plants above a specified height.
Willow species are hosts to more than a hundred aphid species, belonging to Chaitophorus and other genera, [16] forming large colonies to feed on plant juices, on the underside of leaves in particular. [17] Corythucha elegans, the willow lace bug, is a bug species in the family Tingidae found on willows in North America.
Periods of leaf fall often coincide with seasons: winter in the case of cool-climate plants or the dry-season in the case of tropical plants, [18] however there are no deciduous species among tree-like monocotyledonous plants, e.g. palms, yuccas, and dracaenas. The hydrangea hirta is a deciduous woody shrub found in Japan. [citation needed]
Broad-leaved tree. A broad-leaved, broad-leaf, or broadleaf tree is any tree within the diverse botanical group of angiosperms that has flat leaves and produces seeds inside of fruits. It is one of two general types of trees, the other being a conifer, a tree with needle-like or scale-like leaves and seeds borne in woody cones. [ 1]
See also List of Quercus species . An oak is a hardwood tree or shrub in the genus Quercus of the beech family. They have spirally arranged leaves, often with lobed edges, and a nut called an acorn, borne within a cup. The genus is widely distributed in the Northern Hemisphere; it includes some 500 species, both deciduous and evergreen.