Restoration biologists aim to return ecological function to degraded landscapes, by using plants to recreate healthy ecosystems. Landscapes that have been actively disturbed are restored by planting trees, meadows, wetlands and gardens. There is increasing interest to reshape the spaces we have disturbed into healthy and productive ecosystems, with a focus on the use of regionally appropriate native species.
Though we have gone to great lengths to shape the land, plants are the original ecosystem engineers.
Plants are the foundation of every terrestrial ecosystem on earth. Their primary function is to provide animals with food, and materials to make shelter, but they also clean the air, and provide us all with oxygen. Plants also cool us with shade, and buffer us from floods.
Similarly, native plants are the foundation of regional ecosystems they are native to. Though often overlooked as the green backdrop upon which life’s drama unfolds, the specific identity of the plant communities that surround us is important.
Natives are species which occur in a region naturally. They have evolved over generations to exploit resources and cope with challenges found within their home region. Because they have evolved in the same ecosystem, native animals often prefer and sometimes depend exclusively on native plants.
Restoring native plants is a critical first step for conserving ecosystems. Avoiding the use of nonnative plants, especially well documented invasives, in our landscapes will also help to prevent further ecological damage.
The greatest threat to native plant diversity is loss of habitat from development, and the associated spread of exotic plants species. Some of the most invasive plant species in Ontario were introduced with the best of intentions to provide forage for our domestic animals, and to make our neighborhoods more beautiful. The cost of these invasions is more than space; we are paying for these mistakes with the loss of distinct and diverse communities of native plants and their associated fauna. Restoring native species to our landscapes increases the quality of forage and habitat for wildlife, but it also helps us plan for and mitigate the effects of climate change.
Since native plants are adapted to the local environment, they can tolerate regional variations in moisture and temperature better than many traditional, introduced, cultivars. While also being more attractive and rewarding to insects, native wildflowers, for example, are more drought tolerant and cold hardy than their cultivar counterparts, or non-native analogues.
We can use this to our advantage, and plan landscapes of native plants that require fewer inputs, and in the end lower costs to create and manage. There are even native plants adapted to harsh environments that mirror our disturbed urban and suburban environments, such as roadsides and other infrastructure corridors, rooftops, construction footprints, and old fields — native plants that thrive on river bluffs, alvars, sand dunes and fire-prone prairies.
Though they are hardy, wild populations of native plants are increasingly fragmented by development. This makes migration extremely difficult for many plant species in Ontario. Without the ability to migrate, these plants may not be able to cope with a changing climate, and without reconnecting populations through assisted migration, they may fail to adapt to the change. Land stewards who are interested in restoring native plant ecosystems can help by enhancing native plant population sizes and creating gene flow between populations by establishing new patches.
Whether you appreciate nature in the water, casting off the side of your canoe, or you appreciate it in the air, through the lens of your binoculars, conservation begins in the ground with the seeds and roots of native plants.
Article courtesy Stefan Weber, Ecologist – St. Williams Nursery & Ecology Centre