More people are asking for native plants at garden centers and greenhouses, according to my local contacts. What is a native plant? In the simplest sense, it is any plant that was present in a locale before the arrival of European settlers.

But how do we know what plants those were? A forthcoming book by Manuel Lizarralde, associate professor in ethnobotany at Connecticut College, and Jason Mancini, director of the Mashantucket Pequot Museum and Research Center, brings new insight to the question.

Titled “Historical Ethnobotany of Southern New England: Recovering and Repatriating Indigenous Plant Knowledge,” the book documents how regional Native Americans used more than 300 plants before the ships landed. They enumerate the plants’ roles as medicine, food, tools, firewood, shelter, fodder, as “seasonal indicators,” and as part of spiritual practice. Their research draws on a complex variety of written and oral records, some of which date back more than a century. They state, “We need to recognize that the authors of this knowledge are the Native Americans Nations of this region, for sharing this rich body of knowledge.”

The plants themselves are reassuringly familiar, proving that many native species carry on today despite almost 450 years of clear-cutting, farming, paving, and development. Maple, birch, juniper, ash, cherry, tulip, black tupelo, basswood, sassafras, witch hazel, sumac, speckled alder, sweet-gum, white pine, willow, and hornbeam were all part of the scene.

Shrubs popular in today’s garden centers were on the landscape, too, including bayberries, serviceberries, American hollies, inkberries, and winterberries, dogwoods, viburnums, and mountain laurel. Among flowering plants, there were white turtlehead, marsh marigold, blue flag iris, false Solomon’s seal, black cohosh, blue cohosh, golden alexanders, and various milkweeds. Cinnamon ferns and maidenhair ferns were there as well.

Strawberries, raspberries, currants, blueberries, huckleberries, and cranberries were on the summer harvest list. Ground nut, a.k.a. “Indian potato,” and Jerusalem artichoke were on the menu, as were “ramps” or wild leeks.

Chestnuts, which occupied as much as 20% of forested land area, produced massive fall harvests and were a major food source. White oaks, hickory, beech, black walnut, hazelnut, and butternut trees supplied fall and winter food as well. Bullrush, cattail, Indian hemp, and sedges served practical household purposes.

Yet this pre-European landscape was not wild in the strictest sense. According to Lizarralde, it was a “cultural landscape,” shaped, at least partly, by humans. Not every plant was strictly native to the area. Some plants arrived via trade routes from other parts of the Americas. For instance, the well-known “three sisters,” squash, maize, and beans, arrived here around 900 C.E.

Furthermore, the authors list 62 nonnative species that were put to work by local Native Americans after European colonization.

While many species in Lizarralde’s and Mancini’s work are with us today, they live in a greatly altered landscape and, in some cases, only in a commercial setting. Today’s wild chestnuts are blighted, doomed to short and unproductive lives, as are most American elms and butternuts. Had blights of these proportions occurred in pre-settlement New England, they would have caused starvation.

In 2015, the New England Wildflower Society published “State of the Plants: Challenges and Opportunities for Conserving New England’s Native Flora,” by Elizabeth Farnsworth. It documents 3,514 plant species on the modern New England landscape, of which only 70 percent are native. Invasive nonnative species make up a significant percentage of the balance. According to this study and many others, the loss of a single native plant species can disrupt myriad plants and animals. These losses set up a chain reaction in which further native species are undermined.

The forthcoming “Historical Ethnobotany” offers a unique contribution to our understanding of native plants and the human history of the shoreline region.

As for what we buy from garden centers and greenhouses this spring, works such as these make it easier than ever to choose the plants that have a long and successful association with our regional landscape—as well as our regional ancestors.

Kathy Connolly is a landscape designer, garden writer, and speaker from Old Saybrook. Visit www.SpeakingofLandscapes.com.