|MadSci Network: Botany
Plant leaves often contain nongreen pigments, such as anthocyanins and carotenoids, in addition to green chlorophylls. There are many plants with nongreen leaves in which anthocyanins are present in such large amounts that they cover up the green due to chlorophyll. The chlorophyll is still there and functioning however. Examples of plants with nongreen leaves are blue Colorado spruce, red Japanese maple, purpleleaf plum, purple smoke tree and 'Sunburst' honeylocust. Plants with nongreen leaves are highly valued by gardeners and sometimes overused in landscapes. The reverse occurs in green leaves that turn yellow in autumn. Yellow carotenoids were in the leaf all spring and summer but did not become visible until the chlorophyll degraded in the fall. There are a few hundred parasitic plant species that lack chlorophyll so their stems are usually white or yellow. They either lack leaves or have rudimentary leaves. Examples include dodder and Rafflesia. References Re: is it possible to change colours of grass? Re: Are there any plants that do not produce/release oxygen?
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