Evergreen Plants
For your Trivial Pursuits an evergreen plant has its leaves through all seasons. The opposite is a deciduous plant that loses all of its foliage during winter or dry season.
There are numerous variations of evergreen plants, both trees and shrubs. Evergreens are most species of conifers (e.g. hemlock, blue spruce, red cedar and white/scots/jack pine). Live oak, holly and \’ancient\’ gymnosperms such as cycads are included and most angiosperms from the frost-free climates such as eucalyptus and rainforest trees. As with everything in life, there is an exception and that is an African gymnosperm plant that produces only two leaves that grow continuously throughout the plant\’s life but gradually wear away at the apex, giving 20-40 years persistence of leaf tissue.
Leaf persistence in evergreen plants ranges from a few months to several decades.
What are the reasons for being evergreen or deciduous?
The key factors that make a plant either an evergreen or deciduous is temperature, moisture, and soil nutrients. Deciduous trees shed their leaves usually as an adaptation to a cold or dry season. Most tropical rainforest plants are 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, with a predominance of conifers, as few evergreen broadleaf plants can tolerate severe cold below about -30
