Thanks to Frederick Law Olmsted, we can all breathe easier. By the middle of the 19th century, industrialization and urban sprawl threatened America’s natural beauty. Olmsted was a writer and editor whose career took a dramatic turn after a chance meeting with a friend who was overseeing the newly legislated Central Park Act of 1853.

Olmsted became project superintendent and eventually teamed with a partner to design the famous New York park. Olmsted would go on to create some of the first parks open to the public, and his ideas about green space, community planning and public health would set lasting standards that influence landscape architects and urban planners to this day.

His Central Park fame had made Olmsted a full-blown celebrity by the time he met Henry Hobson Richardson in the mid-1860s. Richardson was a young and unproven architect, but the two went on to form an unlikely partnership on a variety of projects, with Richardson’s open interior spaces harmonizing with Olmsted’s wide expanses. Their work expressed a uniquely American style that can be seen throughout the Northeast in projects ranging from private residences to public libraries.

The Olmsted-Richardson collaboration, and how it formed the aesthetic basis of a nation, is the subject of Architects of an American Landscape. We discussed the book with author Hugh Howard, who has written extensively about architecture and art.

Before Olmsted, there was no such thing as a landscape architect. How did that occupation come to be?

There were no city parks when Olmsted became superintendent of what was then the aborning Central Park. When Olmsted was born in 1822, everybody lived within a mile of countryside. If you lived in downtown Manhattan, you could walk north for a mile; if you lived in Boston or Philadelphia, not to mention the provinces, you could encounter nature without any particular difficulty because the development that we think of as big urban areas simply hadn’t happened.

So the need for natural places, for what Olmsted called the “scenic,” was really something that only unfolded within his lifetime and became even more significant over the decades. The American population increased eightfold in Olmsted’s lifetime, between 1822 and 1903. It was necessary then to figure out ways that the landscape could be conserved so that the health-giving properties of the natural world were available to a wide range of people, particularly in the urban areas.

Olmsted felt the “scenic” could breed good mental and physical health, not to mention social democracy. In what ways could parkscapes achieve these lofty goals?

He really took a holistic view of mental health, of physical health. He thought nature had a role in that. He was very conscious of the fact that the rich could afford to go to the Adirondacks for a month in the summer or get on a steamer and go to London and do whatever they wanted. The poor worked six days a week and couldn’t go anywhere except maybe to this park that was within walking distance of their home and get recreative health. There was a restorative power to the natural world that he believed in for poor people as well as the rich.

What do you think is the most important product of the partnership between Olmsted and Richardson? What do we have that we wouldn’t have had if they hadn’t come together?

I think the lesson their collaboration sent to the next generation was integrating a site with a building — how to make a building look as if it grew out of that site. Probably the most memorable structure is the [Ames] Gate Lodge [in Massachusetts]. It’s this little homunculus of a building; it’s this pile of stones that looks like it’s lived there forever. I think that kind of eternal connection of building to a place that was designed by a glacier zillions of years ago — that connection of landscape and structure — is maybe their greatest legacy.

Richardson was the most admired architect of his time, yet his name is unfamiliar to most people today. Has his legacy endured in any way?

A year before Richardson’s death in 1886, 75 architects and builders were surveyed as to what they thought were the finest American buildings. And 85% said Richardson’s Trinity Church of Boston was the finest building, and of the top 10, five were Richardson’s buildings. Two of the architects who became pretty dominant in the next generation, Charles Follen McKim and Stanford White, were former apprentices of Richardson. They formed a firm called McKim, Mead and White in New York that was influential at the turn of the 20th century.

Last summer, wildfire threatened the Sequoia Grove at the heart of Yosemite National Park. Olmsted led early efforts to establish this park, noting the importance of preserving the area while allowing access to it. If Olmsted were alive, would he think we’re doing enough to protect natural areas?

No. That’s the easy answer. I wish Olmsted were alive for any number of reasons. But more than anything else, I wish Olmsted were alive because I like to say that he could see the future. Because he could. When you design a landscape, you have to see the future in some fairly pedestrian way. If you plant a tree when it’s a sapling, you can’t plant it too close to the house because pretty soon it’s going to be too big. I’ve made that mistake. Olmsted didn’t. In that sense, he could see the future of a landscape. But he didn’t merely see how big a tree would grow. He could see not only decades but I think generations into the future, and the survival of his parks as more or less unchanged speaks to that.

I wish he were alive because I think he would have ideas about what we should be doing in our cities, in our parks, to minimize the damage of global warming. I think he would have been all over this for decades. A couple of years ago, there was a hurricane that flooded downtown Boston, and there were a whole bunch of skyscrapers on the waterfront that had three feet of water in their lobbies. The waterworks that he had designed managed that water so that his parks didn’t get ruined in the way that everything around those skyscrapers did. If he were in charge in our time, he’d have some good answers for us.