A tree is described as a perennial woody plant which possesses single stem/trunk and has secondary branches. Height is an important factor that is used for segregating trees and shrubs in separate groups. Most trees generally have a height that varies from 3 m and 6 m. According to some experts, a trunk diameter of at least 10 cm is necessary for a plant to be classified as a tree. There are many different characteristics of trees presented through the information in the following paragraphs.
Different Types of Trees
There are about 20,000 different types of trees in the world. Out of these 20,000 types, 1000 are found in the USA. Different trees found in the world can be grouped into categories like broadleaf, needle-leaf, cycad, fern, and palm trees.
These kinds of trees include various forms of oak trees, maples, elms, ashes, willows, walnuts, etc. Mangroves and mahogany of the tropical region can also be included in this group. Those broadleaf trees found in temperate regions are deciduous in nature. There are however, few exceptions like the live oaks and holly trees which do not shed leaves. Such trees are found in Southeastern USA. Hardwood and broadleaf trees are synonymous. Hardwoods are known for their complexity and robustness that make them useful for a myriad of purposes. The maples trees, beeches, and oaks are known to produce hard wood.
There are around 500 needle-leaf tree species and the pines, hemlocks, firs, spruces, and redwoods are few of the familiar ones. Most of the trees belonging to this category have leaves that are pointed and narrow, while few others like juniper and cedar trees have scale-like leaves. One can find mostly the evergreen trees in this group, however, a few of them like the larch are deciduous. The baldcypress which thrives in swampy areas of Southeastern USA is also one of the deciduous needle-leaf tree.
The palm trees along with lily and pandanus can be grouped together in monocotyledons. Palms are found in tropical regions in the form of coconut palms and also in desert areas (date palms). There are about 2,500 types and different species of trees (palms) found in the world. Main features that can be used in identifying palm trees are trunks without branches and presence of crown at the top. Leaves of palm trees can either be fan or feather shaped.
The common perception about the appearance of ferns is that of short bush-like plants. Fern trees are found in tropical areas. Appearance of these fern trees is much similar to that of palms. These trees however, do not produce cones; reproduction doesn't take place by means of leaves since, flowers are not produced. The fern trees reproduce by means of spores.
The cycad trees have characteristics that are somewhat like palm and pine trees. Feathery leaves and presence of crown at the top are features of cycad trees which resemble the palms. In terms of reproduction, there is a similarity between pines and cycads. Both these plants produce cones which bear seeds. Cycads grow in the moist and warm regions of Asia, Africa, and Central America.