Twelve thousand years ago, as the massive ice sheets from the last period of glaciation were retreating from North America, the land beneath them was left scoured and barren of plant life. Slowly over time, plants and trees migrated northward again. First, algae appeared in pools of water and next, lichens clinging to bare rock. Then as soils began to form from glacial till and atmospheric dust, seeds of various plants blown in by the wind, or transported by birds and packaged with a little natural fertilizer, dropped onto the soils and began to proliferate. Over the next twelve millenia, the northern boreal forest, with maple, pine, hemlock, birch, ash, beech, spruce, and black cherry trees became the predominant forest biome of the northern United States.
Just as the invasive nature of “weeds” causes them to quickly reclaim barren land, the invasive nature of plant life in general drove this reforestation, restoring ecological equilibrium.
Today, there are a number of plants and animals throughout the world that horticulturists, biologists, and some naturalists have negatively termed, “invasive species.” Foremost on the invasive plant list for New England, are European Barberry, Japanese Knotweed, and Purple Loosestrife.
There is one thing to keep in mind when considering "invasive plants," however. It was a human, a member of the most invasive species of large mammal on the planet, that first coined the phrase! Did our ancestors twelve thousand years ago cherish the bare rock of the north to the point that they deemed the incoming plants as invaders, then institute campaigns and weekend forays to prevent them from destroying the beauty of the bare rock? Certainly not! Instead they gratefully accepted the providence of nature and learned to utilize the benefits; functionally, nutritionally, and medicinally of each plant as they could.
We humans are a proud species, believing since the time we first mastered fire making and invented religion, that as the dominant species on the planet we possess a god-given supreme judgement when it comes to controlling our environment. Selfishly employing that judgement for our own interests, we have driven hundreds of species to extinction, disrupted ecosystems around the world, created deserts in the midst of paradise, and generally tinkered like ignorant children with the workings of a system so complex we cannot begin to understand all of its intricacies.
While it is certainly practical to employ organic methods to subdue pests in our own backyard gardens, attempting to control nature on a regional scale is the ultimate homosapien hubris and futility, and as it has in the past, will always result in unforeseen detrimental consequences. Just ask an Aussie about cane toads!
On the other hand, if we work in harmony with nature, starting in our own backyards, neighborhoods, and extended communities to create "backyard wilderness", the benefits will return to us many times over.
Japanese Knotweed is a beautiful ornamental shrub, especially when in flower, as shown above. Brought here from Japan by Frederick Law Olmstead in the 1800's, it has spread rapidly throughout the northeastern United States, especially along roadsides and waterways, choking out native vegetation.
As an invasive, it is despised, but as a wild edible it is prized while a young shoot up to 8" tall, (see photo below,) and can be used to make delicious strawberry-knotweed pie! Japanese Knotweed is also the primary commercial source for the healthful antioxidant Resveratrol.
The photos to the left show European Barberry in flower, then fruiting. Its sharp thorns make this rapidly spreading invasive a great hedgerow shrub, and the berries can be used to make delicious jams and jellies.
All photos are copyrighted and may only be used with permission.