Seasonal Leaf Loss
Leaves in temperate, boreal, and seasonally dry zones may be seasonally deciduous (falling off or dying for the inclement season). This mechanism to shed leaves is called abscission. After the leaf is shed, a leaf scar develops on the twig. In cold autumns, they sometimes change color, and turn yellow, bright-orange, or red, as various accessory pigments (carotenoids and xanthophylls) are revealed when the tree responds to cold and reduced sunlight by curtailing chlorophyll production. Red anthocyanin pigments are now thought to be produced in the leaf as it dies, possibly to mask the yellow hue left when the chlorophyll is lost—yellow leaves appear to attract herbivores such as aphids.
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Famous quotes containing the words leaf and/or loss:
“Black creeps from root to root,
each leaf
cuts another leaf on the grass,
shadow seeks shadow,
then both leaf
and leaf-shadow are lost.”
—Hilda Doolittle (1886–1961)
“Parents must not only have certain ways of guiding by prohibition and permission; they must also be able to represent to the child a deep, an almost somatic conviction that there is a meaning to what they are doing. Ultimately, children become neurotic not from frustrations, but from the lack or loss of societal meaning in these frustrations.”
—Erik H. Erikson (20th century)