Three Evergreens
In various posts over the past few months, we’ve talked a lot about deciduous plants — how their leaves die off in the fall, are shed in most species, and, in a few others, are retained throughout the winter. It only seems appropriate then to complete the picture by talking about those plants whose leaves remain green and active throughout the coldest months of the year — the evergreens! The primary difference between deciduous and evergreen plants is not in whether the plant sheds its leaves, but over what time frame. Deciduous plants tend to be most common in places where there are strong seasonal differences in the availability of crucial resources, such as water or sunlight, which are necessary for maintaining metabolically expensive structures such as leaves. Here in New England, for example, winter temperatures often get below freezing, turning liquid water into ice and making it unavailable for plants to use. At the same time, plants get less access to sunlight due to sh...