Is  changes a noun or a verb in this phrase?

I know that Richard Wilbur was using it as a verb in his poem:

The Beautiful Changes

BY RICHARD WILBUR

One wading a Fall meadow finds on all sides   

The Queen Anne’s Lace lying like lilies

On water; it glides

So from the walker, it turns

Dry grass to a lake, as the slightest shade of you   

Valleys my mind in fabulous blue Lucernes.

 

The beautiful changes as a forest is changed   

By a chameleon’s tuning his skin to it;   

As a mantis, arranged

On a green leaf, grows

Into it, makes the leaf leafier, and proves   

Any greenness is deeper than anyone knows.

 

Your hands hold roses always in a way that says   

They are not only yours; the beautiful changes   

In such kind ways,   

Wishing ever to sunder

Things and things’ selves for a second finding, to lose   

For a moment all that it touches back to wonder.

 

Richard Wilbur, “The Beautiful Changes” from Collected Poems 1943-2004. Copyright © 2004 by Richard Wilbur. Reprinted with the permission of Houghton Mifflin Harcourt, Inc. This material may not be reproduced in any form or by any means without the prior written permission of the publisher.

Source: Collected Poems 1943-2004 (2004)

I am thinking about how the beautiful - or - the faces or images or objects that I called beautiful have changed over my seven decades.

Not ready to answer that right now.