Let it grow
By Kim Deans
A simple strategy I often suggest to farmers embarking on a regenerative path is creating a let it grow area. This is an area of land dedicated to letting everything that wants to grow, grow. No killing allowed. This area can be strategically grazed, taking care to avoid overgrazing which is another form of killing plants. The main criteria are that no killing ever occurs.
Setting aside a defined, permanent let it grow area is useful in cropping enterprises where soils are subjected to constant disturbance. In grazing enterprises, the let it grow approach can be incorporated by leaving out areas when you plan to apply herbicide as part of a pasture improvement program. It would also be useful to leave out areas when applying minerals with the aim of a nicer way to kill weeds. I have had farmers tell me that they have been sold minerals to apply to an area full of thistles, have not gotten around to putting the minerals out and the thistles disappeared anyway. The let it grow area shows us whether it is the product application or whether the weed was going to disappear anyway. Unless we like spending money unnecessarily, it is good to have the ability to see how much we don’t need to do.
When we react to the first sign of weeds with the spray rig, we lose the opportunity to learn from the weeds and can be unintentionally creating the perfect conditions for weeds to continue to thrive. Fleabane is a classic example; each plant produces over 100,000 seeds which need light to germinate. Is it any wonder it continually thrives and develops herbicide resistance in no till cropping systems where the seeds fall on the ground where there is plenty of light because the ground is kept bare of living ground cover? Yet fleabane frequently disappears after one year in a grazing system when left alone and living ground cover improves.
Let it grow areas are our reference point where we can compare our efforts to control weeds with what happens when we leave them alone. We can observe whether a product application has truly delivered the outcomes we seek or if it has created unintended consequences. We don’t have weeds because of herbicide deficiency. Having a let it grow area acts as an early warning system for signs of land degradation and shows us where we are spending money unnecessarily on addictive inputs.
Let it grow areas are a place where we learn from nature and gain confidence working with nature, rather than against it. A place where we observe nature’s successional processes at work in our landscape and under our management. Letting it grow connects us with natural cycles and the role of “weeds” or as I like to call them, indicator plants. A let it grow area provides us with the opportunity to watch indicator plants come and go over time, to witness firsthand how these plants will disappear when they have done their job of healing soil constraints and the mineral cycle. Without these areas these concepts remain a mysterious fiction, something we hear about, might know about but don’t engage with as a practice.
Let it grow areas fulfill a valuable function when we start monitoring soil physical health over time. Having an area where we intentionally keep living roots in the soil so that photosynthesising plants continue feeding the soil food web shows us what is possible when we stop doing harm. It is also a valuable comparison for us to use to identify whether our land management practices are improving or destroying soil physical health in terms of soil structure and water infiltration rates. Without being able to see these observable differences we frequently fail to notice the signs of soil health degradation before it is too late.
Incorporating a pasture ley phase in crop rotations was commonly practiced in the days preceding artificial fertilisers to counteract the obvious damage continuous cropping does to soil health for good reasons. Studies on carbon conversion efficiency, (the percentage of carbon inputs biologically converted to stable soil carbon) have shown root derived carbon conversion efficiency averaged 46% in comparison to just 8% for carbon from above ground biomass. Letting living plants grow and grazing them wisely rebuilds soil organic matter which restores soil structure, fertility, nutrient cycling, and water holding capacity. A let it grow approach can lead us back into harnessing life through using growing plants to restore soil health rather than continuing to accelerate soil health decline through the kill everything approach.
Many farmers we talk with are nervous and fearful about dropping herbicides out of their system and taking a no kill approach. It puts us out of our comfort zone unlearning the beliefs that the industrial farming system has instilled in us: that letting weeds grow makes us a “bad” farmer, weeds will get worse, weeds will take over our land and our neighbours too, that one year’s seeding equals seven years weeding or that we must have a dead fallow to conserve moisture. A let it grow patch is a great way for us to grow our confidence as we navigate a regenerative journey to reach a state of mind where we don’t have “weeds” at all and where we enjoy the benefits of capturing and storing more rainfall, so we get all the rain.
Reference: Jackson, R.B., Lajtha, K., Crow, S.E., Hugelius, G., Kramer, M.G. and Pineiro, G. (2017). The ecology of soil carbon: pools, vulnerabilities and biotic and abiotic controls. Annual Review of Ecology, Evolution, and Systematics, 48:419–45. http://www.annualreviews.org/doi/pdf/10.1146/annurev- ecolsys-112414-054234