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:
“Once they came on a maple in a glade,
Standing alone with smooth arms lifted up,
And every leaf of foliage she’d worn
Laid scarlet and pale pink about her feet.”
—Robert Frost (1874–1963)
“Our loss put six feet under ground
Is measured by the magnolia’s root;
Our gain’s the intellectual sound
Of death’s feet round a weedy tomb.”
—Allen Tate (1899–1979)