The Flight of the Eagle by Alfred Coppel

Humans are a strange breed. Forgetful. They grow accustomed to the wonders they live among so easily that they never really figure up the cost. A little time passes and the bright memories tarnish and are covered over with newer ones. And the men who picked up the check and maybe paid with their lives? Forgotten.

For example, when you're sitting comfortably in the New York to San Francisco stratojet, and you take the trouble to look down at the lush verdure of the eastern slope of the Sierra Nevada, do you ever remember that a few short years back that lovely fertile parkland was a rocky, barren waste? Or when you taste the delicious tropical fruits that are brought to your table from the Mojave Basin, do you think of Bat Kendo, the man who made all that possible? Like fun you do! I'll give you ten to one you never heard of Bat Kendo. Maybe you don't even know that the reason those once sterile wastelands are now the larders of the North American continent is ... weather-plant. And I'll give eight to five you don't even know where that weather-plant came from, or how it got here, or what it cost. Not in money ... in lives.

Well, I know, and for once I'd like to have someone stand still long enough so I could tell the story. The minute anyone sees an old spaceman like me coming, they jet the hell out of there fast. "Old Captain Morley's got another shaggy dog to comb out!" they say, and beat it. My stories, it seems, are too old fashioned for this modern age.