Murray Leinster's "The Skit-Tree Planet" (short story, space opera, free): When humans inadvertently wiped out an alien civilization
Theme is actually a well hashed one - human visitors carry germs fatal to aliens. Leinster turns even this well hashed plot into a very interesting adventure.
Story features a cool & wishful gadget - a material projector. A device that takes a sort of software model of something physical, complete with material properties, & projects that to some targeted physical location. Want to erect a skyscraper? Feed the model & out there is the building. And this building is not just an illusion - it's as physical as anything - so long as the projector is on!
Story summary.Galloping Cow, a spaceship of "the Extra-Solarian Research Institute expedition," has been exploring some star cluster.
They've found 9 puzzling planets on 7 stars in a region covering 200 light years. Massive obviously artificial plantations of "skit-trees ... clumps of thin and brittle stalks which rose straight up for eighty feet and then branched out and bore copious quantities of a fruit for which no human being could imagine any possible use." But absolutely no evidence of anything living, let alone intelligent. No cities, no ruins, ...
Chance on tenth world would make them learn the secret. Not a completely satisfying answer to the puzzle of plantations on 9 other worlds nor why any intelligent being will harvest only one fruit, but interesting adventure while reaching the conclusion.
Fact sheet.First published: Thrilling Wonder Stories, April 1947.
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