Not for human pleasure. Think Darwin. The Washington Post today on the subject:
There are two contending ideas. One is that the red pigments are somehow involved in a Dunkirk-like operation mounted each fall in which the tree salvages useful chemical compounds from the dying leaf and transports them back into the wood for future use. The alternative idea is that redness is a signal to leaf-sucking (and tree-damaging) insects called aphids, which are on the move in the fall and looking for places to lay their overwintering eggs. Aphids don’t like the color red, and the message is: Don’t lay them here; it’s not a good place to raise young aphids.
You may give a red maple leaf to someone for their pleasure, but the maple leaf itself is in it for the tree’s pleasure alone. Not a terribly poetic thought, and it somehow makes it more difficult to pray (were I so inclined). Here’s a poem by James Wright (“Trying to Pray”, 1963):
This time, I have left my body behind me, crying
In its dark thorns.
There are good things in this world.
It is dusk.
It is the good darkness
Of women’s hands that touch loaves.
The spirit of a tree begins to move.
I touch leaves.
I close my eyes, and think of water.
The above poem can be found in Jay Parini’s anthology of poems titled The Wadsworth Anthology of Poetry (p. 1316). It’s an exceptionally good anthology of poetry, by the way, and creative in its arrangement (by genres and themes as opposed to chronology).