When we look at photos from our history, it’s amazing to see the dramatic changes in the landscape. Areas now dominated by houses and neighbourhoods, were once an ecosystem of some kind or another. Whenever humans colonize, we displace species and manipulate the landscape. Whether it’s clearing forests, filling in swamp and bogs, or cutting off natural flood systems, our disturbance can have major impacts to the ecology short term and long term.
Here in Golden, BC, an area dominated by coniferous forests, disturbance by humans has been extensive and dramatic. Lucky for us, the museum has kept records and photos to give us a glimpse back into the past. It doesn’t take much investigation to realize our town was once a mature coniferous forest with areas of swampland and seasonal floodplains.
As the town has grown, more and more areas have been converted to housing and the once dense forest has been opened up, allowing more light through, changing the overall ecosystem to more open savanna and meadow habitats. The one problem is that the native plants that would thrive in this type of new ecosystem are historically absent. Plants, unlike animals, can’t move. They rely on seed dispersal techniques such as wind like those with fluffy parachutes as we seed in sow thistle, or by animals like birds who eat the fruit and distribute the seeds elsewhere. However, some species have a harder time, especially when they have to compete with non-native, invasive species of plants.
Upon moving to Golden, I noticed that in the forested areas, the woodland plants dominated and very few invasive plants could get a foothold. However in the town and areas where forest has been cleared, the plant life is heavily dominated by opportunistic invasive plants like Creeping Thistle, Sweet Clover, Orange Hawkweed, Burdock, etc. At first I didn’t understand why there were no or very few native plants present, but a picture posted by the museum from the 1800’s gave the evidence why.
Typically in nature we see habitat disturbances primarily caused by forest fire, landslides, avalanches, floods, and animal herbivory. These events reset the natural succession, with seeds given an opportunity to sprout with the new opened up canopy, allowing more sunlight to the ground and less competition for water resources. Certain species of herbaceous perennials and annuals are fire specialists, appearing quickly after a fire moves through an area. Plants like Fireweed, Lupines, and Asters, are quick to rebound. As succession continues, shrubs begin growing above the perennials, shading them out. At the same time, tree seedlings are stretching up as well, eventually shading out the shrubs, creating a new forest. This natural cycle can take hundreds of years to eventually regrow a forest, much longer than we humans are used to. And to eventually achieve Old Growth status, this can take millennia.
In our town, we are stuck in perpetual succession which we manipulate by continually mowing and disturbing the soil. Nature does not like bare ground and invasive weeds have taken over in the absence of native plants adapted to our town’s new growing conditions. Additionally, we have vilified native plants for years, which is reflected in their common names. Bugbane, Hawkweed, Devil’s Club. Milkweed, is a previously vilified native plant that is an incredible nectar source for bees, parasitic wasps, butterflies, hummingbirds, and is the only host plant for Monarch Butterflies. By vilifying native plants, we have removed them entirely from our landscapes, which has exasperated our battle with invasive weeds and directly has impacted the biodiversity in our ecosystems where we call home.
We have an opportunity in our town and beyond, to work with organizations like Wildsight and CSISS (Columbia Shuswap Invasive Species Society) to remove invasive plants. But, we also need to add the native plants adapted to our ecosystem at the same time as removing the unwanted. Remember, nature does not like bare soil, thus, while we remove an invasive, we can plant a desired native plant plug in its place.
Why native plants anyways?
Native plants have evolved here for thousands of years alongside our native insects and animals. They are genetically diverse with high variability which helps them adapt to changing climate and environmental challenges. Plants are the keystones, and critical to ecosystem function and biodiversity. Some species of native plants like the Willows (Salix spp.) support over 200 species of insects including numerous butterfly and moth caterpillars. Goldenrod is another great keystone plant that not only hosts many insect larvae but also is a critical late nectar and pollen source for overwintering bumblebee queens. Besides increasing your butterfly populations, you also provide food for birds, naturally. No feeders needed just a mindset shift.
Nesting birds require a steady supply of food for their young, primarily caterpillars and soft bodied insects. And they need a lot of them! A pair of chickadees require 6,000-9,000 caterpillars to rear and fledge one clutch of chicks. This is just one pair of small songbirds. Larger birds require even more. In the fall and winter, migrating birds depend on high fat dogwood berries and seed heads from wildflowers. Leaving up your spent coneflowers could make a winter Siskin very happy on a chilly January day.
Adding native plants is often very easy. Some species of course have complicated germination requirements but most are pretty straightforward to germinate and grow. The one difference however is they require stratification. This means they need a thaw and freeze cycle to break seed dormancy. The most effective way is to plant your seeds in pots and leave them outside all winter in the elements. This allows the seed to naturally germinate.
One thing to consider when growing from seed is to have patience and set your expectations reasonably. Most perennials need three years to fully reach their potential and some require even longer. They spend the first two years establishing roots, often extensive root systems, which allow them to weather dry spells and droughts. Once their roots are well established, many species can persist a long time and require very little from the grower.
A good way to remember to be patient is:
First year they sleep (As they spend energy sending down roots)
Second year they creep (Again they continue to establish their root systems and colonize their spot)
Third year they leap! (This is when they really start to shine and put on a show)
By year five, gaps should be filled in with native plants that have seeded to allow no space for competing invasive weeds.
Helping your native ecosystem can be as easy as incorporating them into your existing garden beds or starting a couple new beds. An easy way is the lasagna gardening technique. They involves mowing the grass very short, adding leaves or grass clippings, two layers of cardboard (tape removed and preferably plain brown cardboard), then a layer of leaves and then finally soil on top. This method smothers the grass below and as your plants establish, the leaves and cardboard break down and are incorporated into the soil. This method also buries the seed bank below which can be harbouring a wave of invasive plants that would awaken if brought to the light. One addition is to create an edge and use either logs, wood planks or plastic edging around your new bed to prevent creeping plants like crab grass from infiltrating your new bed.
Most of us have areas of lawn that we do not use and these areas can easily be made into biodiversity hotspots that help our local ecology. You don’t need to remove all your lawn but increasing the biodiversity by adding native plants is a great addition. If more people did this we could seriously and dramatically help our declining insect and bird populations!

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