Back home now in Maryland after some time in Arizona (near Tucson) with cousins, my mind is full of the beauty and diversity of the cactuses that I saw there -- in yards and gardens and, most spectacularly, at the Arizona-Sonora Desert Museum (BIG Thanks, Bob and Ann!) My interest in these prickly plants led me to seek a poem that featured them. What I found is a small "square poem" in my article "Mathematics in Poetry" -- published several years ago by the Mathematical Association of America (MAA) and available here. Below, I quote that tiny square poem -- preceded by an explanatory introduction.
serve as well
as true ones.