
courtesy Alfred Eisenstaedt | LIFE Collection
Sincerely Yours, Rachel Carson
'Silent Spring' author’s forgotten letter to a Texas biologist is found decades later.
It’s a short note, but it speaks volumes. A bit of serendipity helped Texas state ornithologist Cliff Shackelford discover it.
Rachel Carson was an author and conservationist whose books paved the way for the modern environmental movement. Dan Lay was a pioneering Texas Parks and Wildlife Department biologist who left a legacy of conservation, particularly in East Texas.
Carson, who had a couple of books on ocean life to her credit, wrote a letter in 1959 to Lay (in tiny Buna, Texas) to enlist his help with a new book she was writing “on the subject of the many problems created by the present use of chemical pesticides.”
That book was 1962’s Silent Spring, a landmark work that led to sweeping changes in U.S. environmental policy regarding use of chemicals such as DDT.

Courtesy Population Connection
Shackelford, who considered Lay a mentor, found the letter by accident.
“The letter is dated several years before Carson’s classic book Silent Spring came out,” Shackelford says. “She was doing her research and found out about a Texas Parks and Wildlife employee working on bird surveys and finding bird deaths. She reached out to him. When he passed away, Dan’s widow told me to come over and grab a couple of books from his shelf if I wanted any. I grabbed a first-edition Rachel Carson. I didn’t think much of it and started looking through it a couple of weeks later. The letter was folded therein — an original letter with her signature on it. I flipped out.”
In the note, dated Oct. 30, 1959, Carson wanted to know more about Texas landowners receiving free supplies of a pesticide, heptachlor.
In the 1950s, DDT and other pesticides were exacting a devastating toll on birds, fish and other wildlife, driving bald eagles and brown pelicans to the brink of extinction. Carson was gathering evidence to expose the hazards of the chemicals.

Courtesy Cliff Shackelford | TPWD
Lay, one of the first professional wildlife biologists in Texas, witnessed firsthand what some of the chemicals sprayed in the 1950s were doing to wildlife in Texas.
“Early in 1958 I received a call from Austin to meet fire-ant control agents in Sour Lake,” Lay writes in “Outdoors in East Texas Then and Now,” published in the East Texas Historical Journal. “They planned to apply 15 pounds of heptachlor per acre on the Fralisle Ranch in three days. My instructions were to ‘Please appraise results.’ Birdlife was counted on ranch roads as a small pretreatment sample. Three days after the treatment the Plant Pest Control agents from the USDA acted as if they were shocked that there were no live birds but many dead ones. Also found in water were dead fish, crawfish, snakes and nutria. After a second treatment in May, after more than a hundred nests of dickcissels and blackbirds had been tagged, there was no survival.”
What about the free supplies of heptachlor?
“One consequence of the hysteria about fire-ants was antagonism towards me, as if I had caused the problem,” Lay explains. “This came to a climax in Buna after 50-pound sacks of heptachlor were distributed at no cost. Representatives of the U.S. Department of Agriculture promised complete control of the fire-ant and did not urge caution in its use.”
After Lay died in 2002, many of his files and books were archived in a special collection at the library at Stephen F. Austin State University in East Texas.
Shackelford stared at the letter with Carson’s signature for weeks, then decided what to do with it. He carefully wrapped it up and mailed it off to be added to Lay’s collection.
The Clarence Cottam mentioned in the letter is a former assistant director of the U.S. Fish and Wildlife Service and former director of the Welder Wildlife Foundation in Sinton. The Texas Chapter of the Wildlife Society bestows a Clarence Cottam Award each year for best student wildlife research.
Silent Spring celebrates its 60th anniversary this year. After its publication, the U.S. government banned the use of DDT and curtailed almost all use of heptachlor.
Bald eagles now soar in the skies above Texas, and brown pelicans cruise up and down the coast.
It might have been different. In the chilling fable that opens Carson’s book, she depicts a place where the wildlife was silenced by the effects of pesticides, much like what Lay observed.
“It was a spring without voices,” she writes. “On the mornings that had once throbbed with the dawn chorus of robins, catbirds, doves, jays, wrens and scores of other bird voices there was now no sound; only silence lay over the fields and woods and marsh.”
Russell Roe is the managing editor of Texas Parks & Wildlife magazine.
Related stories
Writers Give Texas Nature the Literary Treatment
» Like this story? If you enjoy reading articles like this, subscribe to Texas Parks & Wildlife magazine.