I'm getting a bunch of little gems in my poem-a-day box from Poets.Org.
This one is really lovely,it has a subplot.It's a poem within a poem! If you can do this, it could cover two 30-30s in one.
by Fred Chappell
The children race now here by the ivied fence,
gather squealing now there by the lily border.
The evening calms the quickened air, immense
and warm; its veil is pierced with fire. The order
of space discloses as pair by pair porch lights
carve shadows. Cool phosphors flare when dark
permits yearning to signal where, with spark
and pause and spark, the fireflies are, the sites
they spiral when they aspire, with carefree ardor
busy, to embrace a star that draws them thence.
Like children we stand and stare, watching the field
that twinkles where gold wisps fare to the end
of dusk, as the sudden sphere, ivory shield
aloft, of moon stands clear of the world's far bend.