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.
Read more about this topic: Leaf
Famous quotes containing the words leaf and/or loss:
“All over France, in every city there stand cathedrals like this one, triumphant monuments of the past. They tower over the homes of our people like mighty guardians, keeping alive the invincible faith of the Christian. Every arch, every column, every statue is a carved leaf out of our history, a book in stone, glorifying the spirit of France.”
—Sonya Levien (1895–1960)
“The greatest dangers have their allurements, if the want of success is likely to be attended with a degree of glory. Middling dangers are horrid, when the loss of reputation is the inevitable consequence of ill success.”
—Philip Dormer Stanhope, 4th Earl Chesterfield (1694–1773)