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:
“With fairest flowers
Whilst summer lasts and I live here, Fidele,
I’ll sweeten thy sad grave. Thou shalt not lack
The flower that’s like thy face, pale primrose, nor
The azured harebell, like thy veins; no, nor
The leaf of eglantine, whom not to slander,
Outsweetened not thy breath.”
—William Shakespeare (1564–1616)
“One writes of scars healed, a loose parallel to the pathology of the skin, but there is no such thing in the life of an individual. There are open wounds, shrunk sometimes to the size of a pin-prick but wounds still. The marks of suffering are more comparable to the loss of a finger, or the sight of an eye. We may not miss them, either, for one minute in a year, but if we should there is nothing to be done about it.”
—F. Scott Fitzgerald (1896–1940)