Жыл бойы жасыл қалған өсімдіктер

Plant that has leaves in all seasons
the type of plant

In botany, an evergreen is a plant which has foliage that remains green and functional throughout the year. This contrasts with deciduous plants, which lose their foliage completely during the winter or dry season.

Evergreen and deciduous species vary in a range of morphological and physiological characters. Generally, broad leaved evergreen species have thicker leaves than deciduous species, with a larger volume of parenchyma and air spaces per unit leaf area. They have larger leaf biomass per unit leaf area, and hence a lower specific leaf area. Construction costs do not differ between the groups. Evergreens have generally a larger fraction of total plant biomass present as leaves (LMF), but they often have a lower rate of photosynthesis.

Deciduous trees shed their leaves usually as an adaptation to a cold or dry/wet season. Evergreen trees also lose leaves, but each tree loses its leaves gradually and not all at once. Most tropical rainforest plants are considered to be evergreens, replacing their leaves gradually throughout the year as the leaves age and fall, whereas species growing in seasonally arid climates may be either evergreen or deciduous. Most warm temperate climate plants are also evergreen. In cool temperate climates, fewer plants are evergreen. In such climates, there is a predominance of conifers because few evergreen broadleaf plants can tolerate severe cold below about 26 °C ( 15 °F). In areas where there is a reason for being deciduous, e. g. a cold season or dry season, evergreen plants are usually an adaptation of low nutrient levels. Additionally, they usually have hard leaves and have an excellent water economy due to scarce resources in the area in which they reside. The excellent water economy within the evergreen species is due to high abundance when compared to deciduous species. These conditions favor the growth of more evergreens and make it more difficult for deciduous plants to persist. In addition, the shelter provided by existing evergreen plants can make it easier for younger evergreen plants to survive cold and/or drought.