I hate admitting how old I am, but I remember that first Earth Day in 1970.

The students from my small town in the foothills of Colorado were bused to a larger school in the district, where a series of speakers and seminars spoke of the urgent need to stem the destruction of the earth’s water, soil and air.

Two years earlier, the first astronauts to orbit the moon had beamed down photographs of the earth. What once seemed vast now seemed tiny. The concept of the earth as our island home was born.

A small group of activists organized Earth Day to galvanize the general public to take action to protect this island home.

Some changes came relatively quickly. The Clean Air Act and Clean Water Acts were passed. The dangerous pesticide DDT was banned two years after that initial Earth Day. The term recycling became a common phrase in our language.

Other changes came more slowly. Organic farming had previously been dismissed as a wacky notion practiced only by small bands of hippies. After Earth Day, some farmers looked at the arsenal of chemicals in their barns and began to wonder if it was possible to produce food without those poisons.

It took a full generation—20 years—from that initial Earth Day for Congress to pass legislation establishing standards under which food could be certified as organic. And, it took another 12 years to develop the initial regulations on how to implement that law.

Earth Day is still a work in progress.

But as I walk into my local supermarket and see the growing offerings of organic food and locally grown produce, I wonder what our island home would look like if a group of activists hadn’t organized that initial Earth Day.