There are many types of trees that grow in different parts of the planet including deciduous and evergreen trees. These trees are categorized based on different characteristics such as the pattern and the foliage growth’s seasonality. In between these two broad categories, there is another classification of trees that is called semi-deciduous trees. These semi-deciduous trees are neither deciduous nor evergreen, therefore, they have characteristics of both types of trees.
Characteristics of Evergreen Trees
In the field of botany, as the name suggests, an evergreen tree is one that is always green throughout the year. A change in season does not affect the foliage or leaves of the tree. However, it does not mean that these trees never lose their leaves. As is the case with the cycle of life, old parts are replaced by new ones and the leaves of evergreen plants are no exception. For some evergreens, the replacement is slow while for others the replacement process is a bit faster. Regardless of the speed, the process does not happen at once.
Such kinds of trees mostly grown in warm and temperate climates such as most of the trees in tropical rainforests. Examples of these trees include the likes of most conifer trees such as pine, red cedar, blue spruce, and others. Other species in this category include the likes of live oak, clubmosses, most angiosperms, and other species.
Characteristics of Deciduous Trees
Deciduous trees, which are also known as coniferous trees, are the direct opposites of evergreen trees. Deciduous trees are those that shed some of their parts, usually leaves, as the seasons keep on changing. In the field of botany, the word "deciduous" means falling off when maturity is attained or a tendency to fall off.
Most of the trees in this category have broad leaves, which ensures that the rate and effectiveness of photosynthesis is relatively high. The shedding of some parts has both negative and positive aspects. For example, shedding of leaves, which is mostly during winter and autumn, means that they are exposed to the harsh conditions of nature in these times. However, despite the exposure to the weather elements, they are usually specially adapted to survival in that harsh period. For example, their broad leaves ensure that they make enough food to sustain them during a period when photosynthesis is impossible. In addition, the water conservation ability of these trees is considerably high.
Some of the deciduous trees include the likes of Virginia creeper, several coniferous genera (like Metasequoia and larch), elm, and birch. In the world, there are two types of deciduous forests, namely temperate deciduous forests and tropical and subtropical deciduous forests. Trees that grow in the former forest respond to changes in temperature as the seasons change while those in tropical forests are sensitive to changes in rainfall patterns as the seasons change.
Differences Between Evergreen and Deciduous Trees
The first and the most apparent difference between the two types of trees is that deciduous trees lose their foliage or some other part of their structure as the seasons change. The reason for this is that these trees grow in regions where the conditions are harsh. Therefore, to preserve nutrients, these trees have to reduce energy usage in winter and autumn. On the other hand, evergreen trees do not lose their foliage at once as the seasons change since they grow in regions where the climate is not as harsh. However, evergreen trees replace their leaves slowly as they age although the speed of replacement varies from one evergreen tree to another.
Another apparent difference is that evergreen trees require higher amounts of nutrients for survival compared to deciduous trees, especially during bad weather conditions. The reason for this higher energy requirement is that evergreen trees do not shed their leaves at that time. As such, the plant needs more nutrients to ensure that its body parts are not damaged and stay in good condition. By comparison, deciduous trees have low energy needs during harsh climatic conditions but have a hike in nutrient requirements immediately after harsh weather during the renewal of foliage.
Deciduous trees have broader leaves compared to evergreen trees. These broader leaves ensure that the plant manufactures as much food as possible during summer and fall so that it has enough sustenance during winter and autumn. Just before the leaves fall, the leaves of deciduous trees lose the ability to manufacture food and lose their green color. By comparison, evergreen trees never lose the green color of their leaves and have comparatively smaller leaves. In terms of the timber they produce, deciduous trees tend to produce hardwoods while softwoods are mostly obtained from evergreen trees.
Habitat and Distribution
In terms of the places where they grow, evergreen trees mostly grow in tropical rainforests while deciduous trees grow in temperate forests or in tropical and subtropical forests. Deciduous trees growing in temperate forests are mainly affected by climate changes, such as temperature and rainfall. Deciduous trees growing in tropical and subtropical deciduous forests are mainly affected by changes in the rainfall patterns. In other words, deciduous trees can survive in regions where evergreen trees grow while evergreens cannot survive in some of the harsh climates where deciduous trees grow. Deciduous trees can survive in places where the temperatures go below -15°F. Since the two types of trees can grow side by side, it is not unusual to some sections of a forest with trees that have leaves while other sections have trees without leaves.
Flowering and Pollination
For the majority of deciduous trees, flowering usually occurs during the time when they are leafless in order to increase the chances of pollination. Leaves usually hinder pollination due to the blockages that pollen has to encounter before reaching a flower. The absence of leaves also ensures that pollinating insects see the flowers easily. By comparison, flowering for evergreen trees happens when leaves are present.
When these two types of trees grow together, evergreens have the ability to ensure their survival since they make the soil more saline and lower the nitrogen content. These conditions, including the protection offered by the canopy, are favorable for the growth of evergreens and not deciduous plants.