What are Native Plants?

Native plants are, in a word, local. They are plants that have been growing in a particular habitat and region, typically for thousands of years or much longer. Also called indigenous, they are well adapted to the climate, light, and soil conditions that characterize their ecosystem. Within this system, they have evolved tremendously important co-evolutionary relationships with the other plants, animals, fungi, and bacteria present, and these very complex relationships keep that particular ecosystem stable.

In Massachusetts, we consider all the plants that grew here prior to European colonization to be native. They had the tremendous advantage of being able to evolve and adapt to evolutionary change at a relatively slow pace that supported their continued survival and that fostered ecosystem stability. Native plants were used extensively by Native Americans, but their environment did not yet include the larger scale disruptions that began after European settlers arrived— introducing non-native plants from other continents, rapidly clearing much of the landscape to introduce new agricultural practices, manipulating the genetics of plants through cross-breeding and now, through bioengineering.

  • The Must-Read Book: Do it!
    Bringing Nature Home book cover.

    Bringing Nature Home: How Native Plants Sustain Wildlife in Our Gardens

    This book catapulted Dr. Tallamy to national attention when it was first published, and provides one of the best and most detailed explanations of the importance of native plants available. It includes detailed data about the importance of many woody species that serve as host plants to different species of butterflies and showy moths. Tallamy's research documents that oaks are the top of the list, hosting over 500 species, closely followed by our native willows, cherries, and birches.

    Contrasting natives with non-natives, we learn that our native flowering dogwood (Cornus florida) supports one hundred and seventeen species of moths and butterflies, while the non-native Kousa dogwood hosts only six species of insect herbivores. Tallamy summarizes his years of extensive research with the conclusion that “native ornamentals support twenty-nine times the biodiversity of alien ornamentals.” And he notes, our native insects are not to be feared, because in a balanced ecosystem, they nibble small enough portions of the plants available so that we hardly notice their presence.

  • Why are native plants so important?

    Native plants are the necessary heart of healthy ecosystems. Plants power the food web for the rest of life on earth. Within this web, it is the balance of co-evolutionary relationships that allows millions of different species to all live closely together within a shared place. In a local ecosystem, only the plants that have evolved over an extended period of time with the other flora and fauna present can successfully feed the entire web and keep it stable.

    • Native Plants Host the Insects We Need
      Native plants host a vastly greater number and variety of insect species than non-natives. And although we humans have been programmed to think otherwise, insects are critical to our ecosystems and therefore to us. For example, insects and other arthropods provide about 60% of the avian diet overall, and they are virtually the sole food source for nesting terrestrial birds. Without insects, our beautiful songbirds couldn’t survive or raise their young. Without ponds and vernal pools teeming with insect life, there would be no spring peepers or amphibians. Insects are a vital hub in our web of life, critical intermediaries between plants and the animal world. We need them and they need native plants.

    • Pollination Systems— Made Possible by Natives
      The vast majority of plants on earth are flowering plants (angiosperms) and most of those are pollinated by animals— primarily insects, but also a few birds, bats, and others. While some pollinators are generalists that can effectively pollinate a small number of plant species, others are specialists that may be able to pollinate only a single plant species! In either case, the shape and structure of a every plant’s flower is quite unique, and the physiology and behavior of its pollination partner(s) create a mutualistic relationship that deeply intertwines the lives of each. Our native pollinators depend upon our native plants, and vice versa.

    • Host-specific Lepidoptera (Butterflies and Moths)
      Many butterflies and moths are host-specific and can only reproduce if they lay their eggs on a single plant genus or species that is edible to their larvae. Our current poster child for this issue is the Monarch butterfly, now widely understood to be able to survive and reproduce only on milkweeds (Asclepias spp.). But such host specificity is relatively common in the Lepidopteran world, showing us why our native plants are so essential to the future of our beautiful butterflies and moths. Only if we re-establish healthy native plant landscapes can we prevent the continued loss of species. In Massachusetts more than 25% of all butterfly species are in serious decline and are considered of conservation concern.

    The Bottom Line: Plants provide the foundation for life by capturing the energy of the sun and converting it into biomass for the rest of us to eat, and native plants promote the biodiversity necessary for balanced ecosystems. Increasing the health and diversity of these organic systems is critical to counteracting climate change. If we humans want to survive and have a sustainable future, it is time to pay attention to the importance of growing natives everywhere.