A good word is like a tree whose root is firmly fixed in the sky.
The Koran

The art of teaching is the art of assisting discovery.
Mark Van Doren

The cultivation of trees is the cultivation of the good, the beautiful, and the ennobling in man, and for one, I wish to see it become universal.
J. Sterling Morton

He that plants a tree loves others beside himself.
English Proverb

He who plants a tree plants hope.
Lucy Larcom

My mother said to me,
When one sees the tree in leaf one thinks
the beauty of the tree is in its leaves,
and then one sees the bare tree.
Samuel Menashe

I lean against a birch-tree,
My arms around it twine,
It pulses, and leaps, and quivers,
Like a human heart to mine.
Amy Levy

I shall speak of trees as we see them, love them,
adore them in the fields, where they are alive,
holding their green sunshades over our heads,
talking to us with their hundred thousand whispering tongues,
looking down on us with that sweet meekness
which belongs to huge, but limited organisms...
Oliver Wendell Holmes

I like trees because they seem more resigned 
to the way they have to live than other things do.
Willa Cather

The tree which moves some to tears of joy is in the eyes of others only a green thing which stands in the way. Some see nature as all ridicule and deformity... and some scarce see nature at all.  But by the eyes of a man of imagination, nature is imagination itself.
William Blake