Weeds! Understanding them and their Uses
Written by Adam Mohammed
What is a 'weed'? Typically we humans describe a plant as a weed when it gets in the way of what we're trying to grow. We often react with frustration, spending vast amounts of time ripping these plants out, or worse, spraying them with toxic chemicals, all without stopping to think; why is this plant growing here? And further, what does it have to offer? Every plant in an ecosystem has a purpose, a niche it fills. Humans have been practicing agriculture long enough that our food production zones have become eco systems in themselves; along with 'weed' species that fill niches, and have evolved alongside us. When we observe any eco system (which includes human ones!), and look hard enough, we can find a purpose for every component.
From this vantage point, let’s view our gardens. A garden is a human mediated eco system, with many of the key functions maintained by human input (fertilization, seeding, pest control, etc.) We've developed quite an attachment to what we perceive as 'ideal' garden conditions. The image of bare black soil, with only our prized tomato growing, its glistening red skin beckoning to us... (Our eyes are most sensitive to the colour red after all). It's neat, ordered, and productive. We know where everything is, and exactly what's happening. But let’s shift our eyes, to the general perspective of the wider ecosystem. Think of a forest, or grasslands, or a marsh. Do you ever see bare soil? Very rarely; with the exception being forests with heavy canopies providing full shade. There are a few instances in which the soil is exposed temporarily. These situations are; after a forest fire, or large scale deforestation by a bug (an increasingly common sight with our reliance on mono culture forestry.)
Let’s take the forest fire situation. Forest fires are a natural cycle in eco systems; at least they were up to sixty years ago, when we started getting very good at fire control. Instead of the 'mega fires' we see know, which sterilize the soil and kill every tree, there were natural cycles of small low intensity fires, which would kill off most of the underbrush and some small trees, but in general, leave thelarge trees alive. The top of the soil would sometimes be damaged by the heat however. This created a niche which was filled by what we call the 'pioneer' species. These species specialized in colonizing recently damaged, bare soil, and reaching down with long tap roots to the undamaged nutrients in the lower levels. They would bring these nutrients up and store them in their leaves, and when the plants died, their leaves would fall to the ground (full of the nutrients that came from the deep). The leaves are eaten up by the surface bacteria, and slowly become the top layer of soil, thereby effectively returning the top layer of soil to a healthy state full of nutrients and minerals! These pioneer species are often call weeds when in reality they are very useful plants indeed.
Let’s think about this, bare, recently disturbed soil . . . sounds suspiciously like a newly tilled garden bed! What we've done is unintentionally associated what we perceive as a 'beautiful' garden bed with what looks to the eyes of our ecosystem as recently damaged soil in need of repair. And so what happens? The pioneer species arrive! And with them, a lot of back breaking work trying to get rid of them. In this series of articles, I'll be exploring common 'weeds', and how, after understanding their niche and purpose, we can work with them, versus against them. It takes a lot of effort to fight against the flow of such an entrenched system. What if we, with a bit of thinking, can channel the forces of these pioneer species to increase the productivity of our gardens, while filling our bellies as well? Every plant has its use; it's up to us to recognize it.