Weeds: the co-worker we love to hate
Exploring the annoying, yet admirable ways weedy species get ahead.
Weeds! I’ve got the weeds. They’re all over our yard and it feels like a very “cobbler’s kids have no shoes” situation for me: a soil practitioner, to have a weedy lawn.
Like anyone else I have the urge to pull them out, and sometimes I do! Weeding can be quite therapeutic after all – y’know the actually pulling of them, not spraying devil’s water on them. I’d literally. never.
Anyway, I wanted to give you my unfiltered thoughts on all these weeds and what my plan is long-term.
What’s a weed?
We call plants, “weeds”, when they’re a nuisance in one way or another. Typically it’s the way they grow that’s a nuisance – pervasive, outcompeting desired vegetation.
Why are weeds always the first to pop-up on disturbed sites?
Why are they so darn aggressive in the way they proliferate?
How weeds work.
In ecology there is a biological strategy theory called r/K selection - super sexy name, right?
r is for reproduction - hey-oh, it IS sexy!
K refers to “carrying capacity” - or is it karrying kapacity?? 😉
r-selected species survival tactic is all about putting a small investment of resources into their offspring, while producing LOTS of them. The babies of such species tend to grow rapidly and do best with little competition, which typically correlates with an environment limited in resources.
On the other hand, the carrying capacity part of K-selected species refers to the idea that the environment of these species, at least during most of their evolution, has been stable at their current population levels. There tends to be competition on an intraspecies level, so success is found by investing a lot of resources into a few offspring to ensure they’re strong and capable to mature and survive.
When it comes to plants, weedy species are strategizing their way through life with the r-selection approach – quick life spans and rampant reproduction. An oak tree on the other hand, leans more towards K-selection (despite the quantity of acorns they can produce, the number of viable offspring is relatively low and the maturation process is long).
This harkens back to our chat on ecological succession! As the ecosystem itself matures, it becomes more stable in the populations of plants and animals it can support. So, in early succession – a time where there are very few resources – a weed has a much better chance of survival than an oak tree. In later succession, the oak tree’s strategy to life will be favored and the weeds will have to spread their seeds elsewhere.
You might be wondering, “a weed can survive in a low quality environment, but wouldn’t it be happy to have more resources too?” The answer is, not really…
It would certainly love having more of the resources it prefers, but a weed is specialized to take up the type of nutrients that are available in a harsh environment. The nutrients found in a more complex environment are different and a weed will have a hard time finding what it needs and ultimately be outcompeted.*
Isn’t that a beautiful thing? They fill a role, and they do their job extremely well.
What weeds lack in versatility, they make up for in specialty.
When soil is left bare, you may notice some of the first plants to pop up are shallow-rooted, low growing / creeping varieties - purslane, spurge, chickweed. Their roots aren’t much, so while they’re not exactly helping build soil, the vegetation is, at the very least, protecting the surface.
This is a source of wonder for me. The morphology of these lateral growing plants may be explained by the fact that the roots are so shallow; they simply couldn’t support an upright growth pattern. But how perfectly convenient is it that the lateral growth happens to protect the soil more than an upright plant would anyway?!
Eventually, tap rooted weedy species show up like dandelion and thistle. We love taproots because they help break up compaction, right? Consider exactly how they do that… it’s not just the mechanical pushing of the root through the soil. It’s also that, with a deeper root, there are at least some plant exudates starting to provide a microbial food source deeper in the soil. This is the very beginning of how nature builds its own soil.
Redefining “Quick Fix”
So, our lot was cleared and compacted with large machinery, sprinkled with an inch of fluffy topsoil, sad-looking sod thrown atop, and nursery trees aggressively planted. Now, can you guess which plants have the most vigor in our yard? That is, the greenest color, reliable flowering, and least amount of pest and pathogen pressure?
Yes, it’s the weeds that are cropping up between the sod seams and along the fence lines. Of course!
I occasionally uproot them so the seeds won’t spread, but I know my real ticket to thriving grass and trees is not going to be through stamping out weeds. That’d be a very long road – decades of labor-intensive hand weeding, resisting synthetic fertilizers and herbicides, and allowing the microbial population to naturally establish itself via ecological succession.
The shorter road to a weed-free future: inoculating, feeding, and protecting the underground world with intention.
This road is more challenging in some ways:
Redefining “quick fix”: our brain loves watching something happen right before our eyes, but perhaps we should reconsider what works and what doesn’t. Is a fix something that kills weeds immediately and needs to be reapplied seasonally, with weeds eventually building a resistance to it? Or is a fix nurturing disturbed land with awareness on the front end and letting it take care of itself for years to come?
Thoughtful Insight: the intentional approach challenges us to know more about the amendments we’re producing or buying. Are we actually applying beneficial biology for the desired plant’s successional group, or is it possible this product is doing more harm than good? Insight can range from key observations - color, smell, texture, etc. - to something as literal as a microscope assessment or proof from the vendor via a biological report.
Stewarding > Piloting: lastly, this approach requires us to regard ourselves as part of an ecosystem – a steward, rather than a commander and operator. As we take responsibility for our role in and impact on our immediate environment we must get still and find our intuition; we must hold space for what we don’t know and be open to observing over weeks, months, and years rather than just minutes and days.
Being a steward is less about obsessing over minimizing your footprint, and more about answering the invitation to be a collaborator with your environment.
What are you taking away from this discussion? Has it provided any answers or evoked any questions? Let me know in the comments below!
Thank you so much for reading. Happy holidays to you and yours.
With Love,
Andie
*In case you’re interested, here’s some more insight into how nutrients differ in successional groups:
As far as soil life goes, early-succession is dominated by bacteria. The main nutrient that becomes available through the predator-prey cycles at this stage is nitrogen in the form of nitrite and nitrate – the latter of which, plants can uptake. In later successional stages, with a greater diversity of organisms comes a greater diversity of waste products. Nitrate becomes less and less dominant, and instead ammonium (NH4+) is the primary form of plant-available nitrogen. Weedy species prefer those nitrate-rich, bacteria-dominant rootzones and won’t be fit to survive in an ammonium-rich, fungal-dominant soil. And vice-versa for an oak tree!
References
Hill, Stuart & Ramsay, Jennifer. (1977). Weeds as Indicators Of Soil Conditions. MacDonald J.. 38.
Kempf, John. May 19th, 2020. Insects consume unhealthy ‘weeds’ growing in healthy soil. https://johnkempf.com/insects-consume-unhealthy-weeds-growing-in-healthy-soil/
Kempf, John. May 4th, 2020. Weeds and crops are never equally healthy in the same soil. https://johnkempf.com/weeds-and-crops-are-never-equally-healthy-in-the-same-soil/
Kempf, John (Host). (2018, May 12). Winning the Weed Control Challenge on Organic Crops with Klaas Martens [Episode 8] [Audio podcast episode]. Regenerative Agriculture Podcast. Libsyn. http://regenerativeagriculturepodcast.com/winning-the-weed-control-challenge-on-organic-crops-with-klaas-martens
Theories of Life History. (2020, August 14). https://bio.libretexts.org/@go/page/14194