The best time to plant a tree was 20 years ago.  The next best time is now. 
~Chinese Proverb

You can live for years next door to a big pine tree, honored to have so venerable a neighbor, even when it sheds needles all over your flowers or wakes you, dropping big cones onto your deck at still of night. 
~Denise Levertov

I frequently tramped eight or ten miles through the deepest snow to keep an appointment with a beech-tree, or a yellow birch, or an old acquaintance among the pines. 
~Henry David Thoreau

If a man walks in the woods for love of them half of each day, he is in danger of being regarded as a loafer.  But if he spends his days as a speculator, shearing off those woods and making the earth bald before her time, he is deemed an industrious and enterprising citizen. 
~Henry David Thoreau

God has cared for these trees, saved them from drought, disease, avalanches, and a thousand tempests and floods.  But he cannot save them from fools. 
~John Muir

I never saw a discontented tree.  They grip the ground as though they liked it, and though fast rooted they travel about as far as we do.  They go wandering forth in all directions with every wind, going and coming like ourselves, traveling with us around the sun two million miles a day, and through space heaven knows how fast and far! 
~John Muir

For in the true nature of things, if we rightly consider, every green tree is far more glorious than if it were made of gold and silver. 
~Martin Luther

Except during the nine months before he draws his first breath, no man manages his affairs as well as a tree does. 
~George Bernard Shaw, Maxims for Revolutionists, 1903

Trees are poems that earth writes upon the sky,
We fell them down and turn them into paper,
That we may record our emptiness.

~Kahlil Gibran

Trees are the earth's endless effort to speak to the listening heaven. 
~Rabindranath Tagore, Fireflies, 1928

The true meaning of life is to plant trees, under whose shade you do not expect to sit. 
~Nelson Henderson

It is well that you should celebrate your Arbor Day thoughtfully, for within your lifetime the nation's need of trees will become serious. We of an older generation can get along with what we have, though with growing hardship; but in your full manhood and womanhood you will want what nature once so bountifully supplied and man so thoughtlessly destroyed; and because of that want you will reproach us, not for what we have used, but for what we have wasted. 
~Theodore Roosevelt, 1907 Arbor Day Message

Trees outstrip most people in the extent and depth of their work for the public good. 
~Sara Ebenreck, American Forests

If I thought I was going to die tomorrow, I should nevertheless plant a tree today. 
~Stephan Girard

Will urban sprawl spread so far that most people lose all touch with nature?  Will the day come when the only bird a typical American child ever sees is a canary in a pet shop window?  When the only wild animal he knows is a rat - glimpsed on a night drive through some city slum?  When the only tree he touches is the cleverly fabricated plastic evergreen that shades his gifts on Christmas morning? 
~Frank N. Ikard, North American Wildlife and Natural Resources Conference, Houston, March 1968

Between every two pines is a doorway to a new world. 
~John Muir

Suburbia is where the developer bulldozes out the trees, then names the streets after them. 
~Bill Vaughn

If you would know strength and patience, welcome the company of trees. 
~Hal Borland

I think that I shall never see
A poem lovely as a tree.
A tree whose hungry mouth is pressed
Against the earth's sweet flowing breast;
A tree that looks at God all day
And lifts her leafy arms to pray;
A tree that may in summer wear
A nest of robins in her hair;
Upon whose bosom snow has lain;
Who intimately lives with rain.
Poems are written by fools like me,
But only God can make a tree.

~Joyce Kilmer, "Trees," 1914

Happiness is a bowl of cherries and a book of poetry under a shade tree. 
~Terri Guillemets

Only when the last tree has died and the last river been poisoned and the last fish been caught will we realise we cannot eat money. 
~Cree Indian Proverb

Us sing and dance, make faces and give flower bouquets, trying to be loved.  You ever notice that trees do everything to git attention we do, except walk? 
~Alice Walker, The Color Purple, 1982