We parked our car in a lot at the eastern end of the Waterfall Glen Forest Preserve and started walking west through a stand of red pines. The Chicago area is not famous for red pines, and these, all the same age and size, planted in neat rows, strongly suggested the involvement of the Civilian Conservation Corps. I don’t know for sure that they planted this little patch of artificial forest, but I know they planted a lot like it.

The first of these giants along our footpath was surrounded by a dense resprout of common buckthorn. This pestiferous European plant–it is, depending on how you define it, either a small tree or a tall shrub–has practically taken over many natural areas. Cut one stem, and ten will grow in its place. Somebody may have cut some buckthorn in this place. The resprouts were young. The slender stems were three to four feet tall, the right size to substitute for wicker in lawn furniture.

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We passed some actual human ruins too. I don’t know who built them. There was a small concrete building with its roof long since gone and a tree growing where its floor had been. Low flagstone walls extended out from the building into the woods on either side. On the lintel of the only door was an inscription: LPS.1921. I suppose the initials could stand for a company name and the numbers could be the date the building was erected, but I prefer to think the inscription should be read “LPS dot 1921.”–an E-mail address left by extraterrestrials.

Shooting stars were in bloom too. These lovely flowers grow on prairies and in open woods. Dense forests, the kind that grow in the absence of fire, are too dark for them.