What is the Imagist movement in American poetry? Imagism

This movement resulted from a reaction to Victorian
poetry that  Imagist poets felt was too sentimental, moralizing, and too conventional is
its diction and form. Rejecting the conformity of such poetry, the Imagist poets sought
to concentrate on the precise rendering of images in free verse.  Ezra Pound and
F. S. Flint first documented the Imagist Movement in the second decade of the twentieth
century.  They called for three primary precepts:  conciseness, musical rhythm, and the
direct treatment of the 'thing,' whether it is subjective or
objective.

Between 1915-1917, American Amy Lowell edited a
volume of the anthology Some Imagist Poets.  One of her poems is
entitled "Generations."   This poem is concise, it has musical rhythm, and it treats its
subject directly.  In this poem, Lowell initially
declares,

You
are lke the stem

Of a young
beech-tree,

Straight and
swaying,

Breaking out in golden
leaves.

Just as directly,
Lowell ends her poem:

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But I am like a great oak under a cloudy
sky,

Watching a stripling beech grow up at my
feet.

In conveying the
contrast, Lowell employs much light/dark imagery: 

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Your shadow is no shadow, but a scattered
sunshine:

And at night you pull the sky down to
you

And hood yourself in
stars.