We’re getting hit harder by drought. Doing the usual things to drought-proof our farms no longer seems enough.
Change is essential – the challenge is to what extent? While no one can blame us for being cautious, we need to challenge our thinking by asking ourselves “what’s the best thing we can do to drought-proof our farms?”
Fortunately, there are farmers leading the way in drought-proofing.
Not a handful – thousands, and they are getting heartening results despite growing food in the marginal country. These farmers were willing to make radical changes because their situation was urgent. They didn’t have the luxury of making changes they hoped would be enough. With no government assistance and low-interest loans – their lives, as well as their livelihoods, were threatened. Arguing that they lacked sufficient funds, time or the necessary equipment and machinery to drought-proof their farms was not an option.
How do they do it?
Growing trees. Yes, it’s that simple. Like many marginal rainfall areas, the southern edge of the Sahel desert in Africa had been open woodlands – scattered trees and shrubs. Massive tree clearing happened from the 1960s for firewood, and because farmers believed that trees consumed precious water and nutrients that would otherwise be available for their crops and pastures.
Over the last twenty years, families have revegetated five million hectares of farmland, increasing their incomes by strategically planting and allowing the natural regeneration of trees within their pastures, arable fields and vegetable plots.[i]
Growing maize under trees in the Sahel.
Why do trees make such a difference for drought-proofing?
Trees store water, create shade, reduce wind, air temperatures and the amount of water lost from the soil through evaporation. But, as I explain in ‘Drought-proof your farm’ and the ‘Eco-logical Farming Handbook‘, by growing trees and other extra vegetation, we dramatically increase the amount of rainwater infiltrating and stored in our soil.
When given a plentiful, regular and preferably diverse diet of organic materials from shoots and roots, and root exudates (the sugars and proteins plants release from their roots), soil organisms construct soil which water readily infiltrates and is stored.[ii] Research demonstrates that something as simple as planting trees in paddocks increases water infiltration three-fold.[iii]
Some farmers I meet are concerned that trees will suck more water out of the ground, but research demonstrates that increased water infiltration and storage in soil, due to the extra organic matter and enhanced soil structure, more than compensates.[iv]
Growing vegetables under trees in Africa.
What’s critical to realise is that the:
1. Warmer (and wetter) your climate, the more food your soil organisms need to do their job. That’s why – silvopasture, the raising of animals among trees, is ranked across Africa, Asia and South America as the most important climate-smart intervention graziers can make,[v] and arable farmers and horticulturists in these regions are starting to grow cereals and veggies using agroforestry designs.
2. It’s difficult to maintain grass cover under trees using set-stocking or rotational grazing, as the grass gets continuously trampled by livestock camping under the trees. Mob grazing techniques like holistic planned grazing move livestock on allowing grass to recover.
3. Improving the condition and number of shelterbelts, patches of remnant vegetation, riparian and other natural vegetation help, but these actions are not sufficient.
We need to skillfully plant and allow the natural regeneration of trees within our pastures, arable fields and market gardens, and to develop other ways to grow more plant biomass using practices like polycultures, alley cropping, cover crops, living mulch, and green manure.
In ‘growing up’ – using the vertical space we have available, we create opportunities to grow extra forage and emergency stock feed for livestock and, like the African farmers, create additional income streams by selecting tree species producing fruit, nuts, seeds, construction timber, pollen, nectar for bees, etc.
We also reduce flooding, sequestrate more carbon in our soil and vegetation, and increase rainfall. Yes, it’s true. We now have evidence that when we grow more trees, rainfall increases!
Farmers using trees in Australia for drought-proofing
Unfortunately, when you mention growing trees many Australian farmers just think of Leucaena (Leucaena leucocephala). Palatable and productive, it has been the species of choice for pastoralists, but there are many other valuable species.
Graziers Shane and Shan Joyce, have realised the value of their tree cover as part of their strategy to build “an antifragile landscape”.[v1] Land with natural revegetation of Brigalow scrub (Acacia harpophylla), a nitrogen-fixing tree, yields nearly 40% greater return than areas wholly cleared.[vii]
Ben and Andrew Sippel have “taken weather out of the equation” and tripled their carrying capacity for sheep by adding saltbush (Atriplex species) as an extra layer of vegetation in their paddocks. Saltbush is water-efficient, and “provides shelter to the grasses, allowing them to grow well.”[viii]
Malcolm Donaldson maintains his cover of Kurrajong trees (Brachychiton populneus) as fodder for cattle during droughts.[ix]
On our farm in far north Queensland, we’re seeing the benefits of combining holistic planned grazing with silvopasture, and tree alleys for windbreaks. The grass under the trees stays green longer into the dry season and continues to photosynthesise later in the morning than grass growing in the full sun. In the bananas and orchard, the overstory of open-canopied legume trees is also designed to provide ‘protective cropping’ by reducing sunburn on our fruit.
Getting practical with drought-proofing
By asking “what’s the best thing I can do to drought-proof my farm?” you’ll do the major re-think necessary to take you beyond hoping that what you do will be enough.
Start small by trialing techniques to see what works best. Get your seeds, seedlings and planting materials ready for when the rain does come.
In Niger, farmers convert approximately 250,000 hectares of farmland each year, despite getting little or no rain. By controlling grazing, tree suckers grow up to 2m within the first year, and within 2-3 years the trees are 4 to 5 m high.[x] In areas where farmers can’t rely on natural regeneration, or they want to grow particular species, they plant seeds and young trees.
Digging half-moons for planting (©FAO/Giulio Napolitano)
Find out why this ‘eco-logical’ approach to drought-proofing works and how to use it on your farm – Drought-proof your farm.
[ii] Wendy Seabrook, 2019, Ecological Farming Handbook. Learning from Nature Publ.
[iii] U. Ilstedt, A. Malmer, E. Verbeeten, D. Murdiyarso, 2007, The effect of afforestation on water infiltration in the tropics: a systematic review and meta-analysis. For. Ecol. Manage., 251 (2007), pp. 45-51 (https://www.sciencedirect.com/science/article/abs/pii/S0378112707004665)
[iv] Andrea D. Basche & Oliver F. Edelson, 2017, Improving water resilience with more perennially based agriculture. Agroecology and Sustainable Food Systems, Volume 41, 2017 – Issue 7 (https://www.tandfonline.com/doi/full/10.1080/21683565.2017.1330795)
[v] Bringing the Concept of Climate-Smart Agriculture to Life. Insights from CSA Country Profiles across Africa, Asia, and Latin America. Sova, C. A., G et. al. 2018. “Bringing the Concept of Climate-Smart Agriculture to Life: Insights from CSA Country Profiles Across Africa, Asia, and Latin America.” World Bank, and the International Centre for Tropical Agriculture, Washington, DC. (https://elibrary.worldbank.org/doi/abs/10.1596/31064)
[vi] Shane Joyce, 2014, Building an Antifragile Landscape, Soils for Life National Forum (https://www.youtube.com/watch?v=rNBTCJNGv5A)
[vii] Soils for life, 2017, Dukes Plain’ – Continuous improvement of the farm resource. Soils for Life Regenerative Agriculture Case Study 2017 (https://www.soilsforlife.org.au/case-studies/duke-plain)
[viii] Hannah Powe, 2019, Saltbush helps drought-proof Narromine farm. The Land 6 Feb 2019 (https://www.theland.com.au/story/5884436/drought-proofing-the-land-with-saltbush/)
[ix] Lara Webster and Haley Craig, 2018, NSW farmers take up tree lopping to feed drought-stricken cattle. NSW Country Hour 21st December 2018 (https://www.abc.net.au/news/rural/2018-12-21/drought-stricken-farmers-lop-trees-to-feed-cattle/10633486)
[x] Tony Rinaldo, 2008, The Development of Farmer Managed Natural Regeneration, Permaculture Research Institute (https://www.permaculturenews.org/2008/09/24/the-development-of-farmer-managed-natural-regeneration/)