Leave it to John Simon to point out an actress’ declining beauty so delicately (he once described an actress’ exposed breast as “uberous,” i.e., copious, abundant – a word you can’t find in most dictionaries). But the word I didn’t know was marcescence.
Looking the word up online, I found an excellent article on the subject, “Winter Leaf Marcescence” from the Clemson University Cooperative Extension Service Home & Garden Information Center:
Have you noticed the persistent brown leaves still hanging on some deciduous trees long after their foliar companions have fallen? This usually becomes very apparent after normal leaf drop in early winter. These brown leaves may remain attached until spring bud growth pushes them free.
Complete leaf drop (abscission) may not occur on some trees until spring, or they may drop from all but lower limbs on other tree species. This is foliar marcescence, which comes from the Latin, marcescere, and means “to fade”. The persistent leaf does not readily form an abscission layer at the base of the leaf petiole (leaf stalk), where it attaches to the twig. This allows these brown leaves to remain attached on trees much longer.
A question that arises, though, does this marcescence benefit the trees or is it a detriment? Indeed, strong winter winds and snow may have a more harmful effect on a tree possessing foliage by causing more branch breakage. However, several theories proposed by plant ecologists suggest that leaves that drop later in the spring will provide a fresh layer of leaf mulch around the tree that helps conserve soil moisture, and these leaves decompose later during springtime to recycle and provide additional nutrients for growth. Another theory that seems to make sense is that lower limbs holding onto these dry unpalatable leaves may deter browsing by deer, who prefer to feed on the more tender and nutritious buds and twigs, not on the bitter, fibrous old foliage.
Whatever the reason for the marcescence, it is an interesting characteristic to see, and if you listen closely, you can hear these noisy, rattling leaves during the winter breezes.(2)
What a lovely description of a natural phenomenon. My thanks to John Simon for once again expanding my vocabulary, even if was at the expense of Ava Garner.
(1) Private Screenings (New York: Berkeley Medallion Books, 1967).
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