Radies Wetland Construction
Wayne and Wendie Radies had a vision for the wide weedy ditch on their property. They imagined a small pond surrounded by lush vegetation, full of birds and frogs. In 2015 after applying for the appropriate permits OSS set out to help make their dream a reality. The image to the right shows the area before any restoration started. There is lots of green in the before photo but most of the plants seen are non native grasses or invasive weeds.
After permits were in hand, the first step when creating a wetland is to dig a test hole. Test holes allow you to have a look at what is going on underground and can help you to learn if you are digging in the right spot. Sometimes you will dig a test hole and it will fill with ground water. If you are counting on ground water to maintain water levels in a pond it is best to leave the test hole for at least one full year to assess water level in both wet and dry seasons.
In our case we did not find ground water but we did find lots of clay. Clay can be compacted into a water tight layer in order to hold water that is coming into the pond as run off.
The excavation and planting on the site was undertaken in collaboration with the wetland institute and renown wetland construction expert Tom Biebighauser.
Once we were ready to start creating a compact clay liner for our wetland, we needed to save any native plants already on site. In our case there were some nice sedges around the water line. Having an excavator already on site made it easy to scoop them up and store them out of the way until we were ready to replant them.
Top soil was then removed and piled out of the way while the clay liner was compacted. The compact clay liner was created by getting layers of clay damp and then tamping them down with the excavator and a steam roller.
Once the bioliner was complete the next step was to replace the top soil. We also brought in some river rock and placed it in strategic locations to reduce erosion. River rock also provides additional habitat complexity. Crevices between stones provide hiding places for aquatic insects and amphibian larva.
Even native plants need a little help to get started. Overhead sprinklers were set up by Wayne to water in the newly planted trees, shrubs and grass seed. This planting will receive supplementary water during our hot dry summers until the native plants have a chance to establish themselves and grow deep roots. We generally expect that native plants will need 2-3 years of watering in order to become established.
With 25 volunteers from the Wetland institute and, landowners Wayne and Wendie, nearly 700 native trees and shrubs were planted in under 2 hours. We also replaced the salvaged sedges along the new high water mark (determined with surveyors equipment) and spread 25lb of native riparian grass seed.
In order to choose the native plants we would plant, we looked to adjacent riparian areas and came up with a wide variety of plants that included cottonwood, red osier dogwood, native willows , nootka rose and snowberry.
For a quick rooting cover crop the wetland institute suggested fall rye which was also spread on site. This excavation took place in the fall of 2015 and we wanted to get something rooted before fall and winter rains washed the soil down into the pond.
Finished!... Well not quite. This is the site after all the planting and seeding but the work isn't finished yet. The easiest part of wetland and riparian projects is the planting.
The rich wet soils of our wetlands mean that plants grow quickly, but invasive plants often grow even faster than our native plants.
Ongoing maintenance needs to be considered whenever undertaking such a project.
By the spring of 2016 the fall rye had really sprouted! Unfortunately it was so tall and lush that our little native shrubs weren't getting any light. Additionally lots of exposed soil means lots of happy little weed seedlings so the next step is to weed!
The tall healthy fall rye produced a bountiful crop of seeds which led to some very happy ducks and pheasants but also an explosion of the population of meadow voles.
Meadow voles are a native rodent that is an important part of the food chain. They are food for coyotes, hawks, owls, bobcats, weasels and other predators.
During the cold winter months meadow voles remain active. One of their food sources throughout the winter months is the nutritious bark from shrubs and young trees. The large population of voles though good news for the neighbourhood hawks was bad news for our young and tender native plants.
Native plants like this little common snowberry (left) were surrounded with a layer of mulch. Mulch helps retain moisture in the soil, releases nutrients as it beaks down and suppresses weeds.
Many of our native shrubs are able to survive getting nibbled and did start to resprout from the roots. Unfortunately these teeny plants need sunlight to thrive and they don't grow as fast as the weeds.
That means that we needed to do lots of weeding to ensure that our native plants had sunlight and space to grow. Weeding was done by hand pulling, digging out roots or brush cutting depending on the species of weed and the best information available on methods of control.
After 3 and a half years of work the native plants are growing, and wildlife is using the area. There is still lots of work that will need to be done to make sure that this wetland thrives and becomes a thriving oasis for wildlife.
Below are some of the wildlife that are using the wetland including mallard ducks, killdeer and pacific chorus frogs.
We hope that as the native vegetation continues to establish and grow it will be home to many more wildlife species.
Many thanks to Wayne and Wendie Radies for their vision, support and patience with this project. Funding for this project was generously provided by Habitat Conservation Trust Foundation, Environment Canada's National Wetland Conservation Fund, Wildlife Habitat Canada, and the Okanagan Basin Water Board.