How is the beauty of nature reflected in this poem?

"A Shropshire Lad 2: Loveliest of Trees, the Cherry Now" is a poem by A.E. Housman. Housman was both a poet and a classical scholar. Many of his poems, including "Loveliest of Trees, the Cherry Now," touch on themes of the inevitability of death. Many of them also celebrate the beauty and youthfulness of nature.
This poem is filled with descriptions of the cherry tree, which is in bloom for the spring. Housman also talks about the "woodland" in which the cherry trees can be found, so we know there are other trees around, and we can begin to imagine the scene.
Now, how does Housman use language to present this as beauty? I believe the answer to that comes mostly from the first stanza:

Loveliest of trees, the cherry now
Is hung with bloom along the bough,
And stands about the woodland ride
Wearing white for Eastertide.

He uses diction such as "loveliest," which has a very positive connotation. He also personifies the cherry tree by saying that it's wearing white for Easter. By presenting this image, we may imagine a white dress, and we can begin to compare the tree to a beautiful woman.
Other phrases, like "bloom along the bough," paint a picture of how the tree looks covered in flowers and can help us visualize the cherry tree as something light, bright, and beautiful.
https://www.poetryfoundation.org/poets/a-e-housman