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:
“So near to paradise all pairing ends:
Here loveless birds now flock as winter friends,
Content with bud-inspecting. They presume
To say which buds are leaf and which are bloom.”
—Robert Frost (1874–1963)
“...to many a mother’s heart has come the disappointment of a loss of power, a limitation of influence when early manhood takes the boy from the home, or when even before that time, in school, or where he touches the great world and begins to be bewildered with its controversies, trade and economics and politics make their imprint even while his lips are dewy with his mother’s kiss.”
—J. Ellen Foster (1840–1910)