What words complete Joyce Kilmer's stanza, "I think that I shall never see a poem as lovely as ____"?

Alfred Joyce Kilmer (December 6, 1886 – July 30, 1918), an American writer and poet, fame is attributed to his short poem “Trees,” which follows below, was published in his 1914 collection “Trees and Other Poems”. The poem, essentially, is a tribute to the magnificence of nature, with Kilmer marvelling at the life of a tree, weathering seasons after seasons. Kilmer's final stanza is well-remembered, “Poems are made by fools like me, but only God can make a tree,” hinting that he feels inferior to nature.

“Trees” by Joyce Kilmer:

I think that I shall never see

A poem lovely as a tree.

A tree whose hungry mouth is prest

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 made by fools like me,

But only God can make a tree.