Come winter, and our streets, footpaths, building premises, rooftops, any horizontal surface in the sight is covered with dry leaves. From time to time, we sense acrid smoke coming from neighbor’s backyard, from the side of the street, where leaves are being burnt. But the leaves are bio-degradable and with time will eventually decompose to go back to soil. So, is there really a need to burn the dry leaves?
Simply preventing people from burning dry leaves was not the solution. Soon enough, there will be piles of dry leaving racked up and then what? What if, there was more that one could do with the dry leaves? As in was there a consumer friendly product that this can be transformed into such that a marketplace is created for brown leaves?
The Eureka Moment!
In places like Pune and Bangalore where there is a space crunch, owning a house with a garden is considered a luxury. So, people are looking towards terrace and balcony gardens to make the best use of the space that they have. The challenge then is to acquire soil for such practices. As has been the practice conventionally, plants are grown in soil usually acquired from third parties like nurseries. In doing so, not only is the source region being deprived of soil, this adds to the plantation cost. So, what can such small-scale gardeners do? The solution was then found in compost made of dry leaves and kitchen waste. Sometimes along with soil, if it is available and sometimes completely without soil. Like this, these gardeners are in constant need of dry leaves and there are people with dry leaves to offer. So, there was the answer- a demand-supply ecosystem for dry leaves. This may sound like fantasy but to Aditi, the Founder of Brown Leaf Forum, the pilot project yielded phenomenal response.
How does nature do it?
First things first, why do plant shed leaves? Water absorbed by the roots of the plant is distributed to all parts of the plant and gets evaporated through leaves and this is called transpiration. Leaves have pores on them called stomata that open and water is let out. At the same time, stomata allows Carbon dioxide (CO2) which is essential for plant for performing photosynthesis allowing them to prepare their food through this process. Also, letting out water helps trees to cool off. After winter, there is summer- the dry season. This is the time when it is necessary to save water, for us and for plants as well. Nature has an ingenious solution for this- get rid of the leaves!! Deciduous trees shed all the leaves. For some duration, there is not a single leaf present on these trees. Shedding leaves not only helps trees, but also helps the soil. Leaves that fall off from the tree, cover the soil around the tree forming a layer over the soil blocking the sun light from reaching the soil thereby allowing soil to retain moisture. In forests, or any natural landscape, when rains come, leaves decompose and nutrients from them are returned to the soil. That is the circular system of nature. Output of one system goes as input to some other system. Hence there is no waste. Dry leaves is never a problem in the natural landscape.
How humans should NOT do it?
In our cities and towns there is no space as most of the surfaces are covered with roads, building, tiles, paver blocks, etc. Of the minuscule amount of space left for this natural decomposition to work, we do not like seeing heaps of leaves. We see them as trash that need to be removed. Our current solution- set the dry leaves on fire.
But this does not solve the problem, in fact, gives rise to many more. People need to understand that burning leaves using open fire means smoke is inhaled by people around and is carried by winds and reaches even people quite far from the place. Burning leaves releases particulates that can give rise to respiratory ailments ranging from minor coughing to major long-term respiratory problems and it is even worse from people who already suffer from asthma or other breathing disorders. Just like any other organic matter, leaves are also made up of carbon and upon smothering releases carbon monoxide (CO) which poses significant health risks like reduction in the oxygen-carrying capacity of the Red Blood Cells (RBCs) aside from contributing to the global warming. One thing that humans should learn from forest fires across the globe, especially the recent Australian bush fires is that the fire spreads with wind and can easily spread to surrounding areas causing significant damage to property and livestock. Also, burning the dry leaves disturbs the environmental balance. Trees absorb various nutrients from the soil of which some percentage is also present in these dry leaves. When leaves are burnt, we lose those nutrients. The nutrients that would have nourished the soil, get destroyed. In all, burning off dry leaves is entirely lose-lose situation. We lose clean air & beneficial nutrients for our soils.
How humans should do it?
The answer to this as explained by Aditi, is a simple 3 fold-strategy of managing dry leaves in eco-friendly manner giving rise to a circular ecosystem. First option is to adopt mulching that is the process of mimicking what happens in natural landscape. We cover the soil surface, in garden, in plant beds, in pots and planters with crushed dry leaves. Layer of dry leaves helps soil retain moisture. Second option is composting– In natural landscape, with monsoon, dry leaves decompose, and nutrients are returned to the soil. In our case, it is not possible to let dry leaves remain where they have fallen and let rains take care of it. Hence, we should collect the leaves, and proactively do the process which nature would have done at its pace. Lastly, the option could to consider leaf donation– At times, quantity of dry leaves is so much, that even after mulching and composting, there are surplus leaves. Or sometimes it is not possible for somebody to practice these options, then this is the 3rd option, leaf donation which is the exchange of dry leaves from people who have dry leaves to the people who want dry leaves. As setup by the Brown Leaf Forum, no financial transaction takes place, that is the beauty of the system. Nobody pays any money to each other. It all happens in the spirit of collaboration. Both of them are simply helping each other. Leaf-donor has surplus leaves, which (s)he donates to leaf-taker who needs them for mulching and composting.