Welcome to the forum from the BBC World Service, I'm Bridget Kendall.
In January 1958 a letter was sent to the Boston Herald along established American newspaper.
The writer, Olga Owens Huckins,
was outraged by what seemed like a senseless killing of wildlife by airplanes spraying a mix of the chemical pesticide DDT and fuel oil over the countryside in an apparent effort to reduce the number of mosquitoes.
The mosquito control plane flew over our small town last summer.
Since we lived close to the marshes we were treated to several lethal doses as the pilot criss-crossed our place.
The shower killed seven of our lovely songbirds outright.
We picked up three dead bodies the next morning right by the door.
On the following day one robin dropped suddenly from a branch in our woods.
All of these birds died horribly and in the same way their bills were gaping open and their splayed claws were drawn up to their breasts in agony.
Olga sent a copy of that letter to her friend,
the American writer and scientist Rachel Carson as a plea to help stop the indiscriminate killing of the birds.
By the late 1950s Carson was a well-known writer of books on marine biology and although she'd always wanted to open the eyes of her readers to the beauty of nature she was by no means a campaigner but the letter revived an interest in a story that she'd been mulling over for many years,
the dangers that agrochemicals pose both to humans and to the rest of nature.
So Rachel Carson turned that story into a best-selling book called Silent Spring,
a book that transformed how America and perhaps the world thought about the environment.
What made Silent Spring so popular?
And what lessons can we draw from it today as we face new environmental threats?
In this forum I'll be looking for the answers and telling the story of Rachel Carson and of her book Silent Spring with the help of three experts.
Dr. Sabine Clark is senior lecturer in modern history at the University of York here in the UK with a particular interest in the history of synthetic insecticides.