Why are Native Plants Important?
Native plants are those that occur naturally in a region in which they have evolved, without human introduction. Native plants have co-evolved with animals, birds and other organisms over thousands of years, in response to the physical features of a region, such as soil, climate and geography. Regions which share the same ecology are called ecoregions.
A well known example of this co-evolution is the fact that our native monarch butterflies lay their eggs only on milkweed family plants. Like the monarchs, a substantial number of insects, called specialists, prefer certain plants, called host plants, to complete their life cycle. However, research suggests that even the generalist bees (those that visit many flowering plants) are four times more likely to visit native plants.
Insects pollinate 85.5% of all plants on earth, including the plants we need for food. But insects rely on plants for their survival; plants are the basis of the food chain. Because of human-driven habitat loss, the number of pollinators has fallen, some to the point of extinction.
What is our Native Plant Region?
The most commonly used term to designate our ecoregion is the Northeast. (referring to the northeast USA and eastern Canada). Our local Harriet Irving Botanical Gardens (Acadia University) designates the Acadian Forest as our ecoregion, an area that is located within this northeast region. However, they do not provide a plant list, whereas there are a number of lists for Northeast North America (in books or on web sites). Make sure you access North American organizations such as the Xerces society rather than USA groups, so that Canada is included.
Our Butterflyway Project has prepared a select list of native perennials and shrubs that are recommended for the home garden. See “Plant Lists” in this same Learning Centre section.
Why Put Native Plants in Our Gardens?
World-wide, we are in the midst of a biodiversity crisis, with insects and other wildlife disappearing at an alarming rate. There are multiple human-based causes for this such, as the effects of climate change and the use of pesticides, but by far the biggest cause is loss of habitat. And much of the remaining unsettled land is fragmented and may contain invasive non-native plants which choke out the native plants.
It is typical to believe that there is enough wild and natural areas for wildlife, but this is no longer the case. We need to give more land back to nature. The biggest untapped resource is outdoor urban and suburban public and private lands. If most of these areas were filled with appropriate communities of native plants, the result would be a vast connected landscape that would support a huge amount of insects, birds and other animals.
These new wildlife habitat areas, with less lawn and a rich layering of trees, shrubs and herbaceous plants, would have many other benefits besides supporting wildlife. These include carbon sequestration, urban shading and cooling, watershed protection, weather moderation, and air cleaning. In the individual garden, more native plants would mean the use of less water, chemical fertilizers, herbicides and pesticides, and motorized equipment, and ultimately, less maintenance.