The role of Mee tree in paddy cultivation
Local farmers planted 3-4 Mee trees per acre of paddy field. These trees were planted in the water inlet areas as well as the water outlet areas since they have a deep as well as a superficial root system that prevents soil erosion at the water entry and exit points. Ancient farmers were also aware of the fact that by planting Mee trees at water exit points, nutrition-rich liquid fertiliser would be carried away to downstream paddy fields.
The irrigation system of the Nuwara Kalawiya region had been designed in such a way that water from one lake flows into another. The water from one paddy field joins the canal carrying waste water and thence to the adjacent lake or paddy field. Since this stream of water flows across a plantation of Mee trees, nutrient components mix with the water and are carried to the adjacent field. This is evidence that the ancestors had efficiently combined the irrigation and agricultural systems with elements of the natural environment and is a testament to their indigenous knowledge as well as their altruistic attitudes.
Farmers knew the chemical properties of the various parts of the Mee tree and took advantage of having these trees at the water inlet points of paddy fields. Chopped roots of the Mee tree exposed to water helped to control insect larvae and pupae in the paddy field (Irangani and Shiratake, 2013). Ancient farmers would also select a Mee tree in a specific location of the field, remove a certain number of rings from the bark and place them in the water inlet or mix them with sand and spray to the field in order to get rid of rats. The seeds of the tree were chopped and sprayed to the field to get rid of paddy bugs (Jayatissa, Dissanayake and Perera, 2019). The oil extract from the seeds was used as a natural pesticide against Kola hakulana dalambuwa (leaf roller – Cnaphalocrocis medinalis ) (Irangani and Shiratake, 2013). The oil was also used to light oil lamps in the paddy field to prevent insects such as paddy bugs from destroying the produce (Jayatissa, Dissanayake and Perera, 2019). By such methods, the farmers managed to control pests without the use of harmful agrochemicals.
The flowering season of the Mee tree attracts insects and birds to it (for the nectar of the flowers and for the fruits) and creates a natural food chain around the tree. This natural food chain attracts various predator birds towards the paddy field which naturally reduce the pest infestations. Also farmers placed the petiole of coconut leaves at different locations around the paddy field as resting places for birds. This allow the predator birds to rest on the paddy field further reduce the pests. These petiole of coconut leaves functioned as a resting site for owls at night who hunt rats who damage paddy in its final growth phase as well. By this method, the farmers were able to attract birds across the field and encourage natural pest control. The insects themselves attract insectivorous bats who feed on them and eventually help control the pests.
The fruit of the Mee tree is one of the favourite meals of the fruit bat (Old World fruit bats, Pteropus flying fox). Swarms of bats arrive and consume the fruits once they are ripe enough and leave bite marks on the remaining fruits (Figure 4). By the dusk of the second or third day, these fruits too ripen and the villagers believe that these bats have the remarkable ability of flying back in search of the fruits that they marked. Occasionally, the bats would carry a few ripe fruits back to their roosting sites. The fruits that fall from their grip along the journey gets planted in the vicinity and is a reason for the abundance of Mee trees around the roosting sites of bats. The excrement produced by bats (guano) after consuming the fruits of the Mee tree is a source of organic fertilizer for paddy fields. These stools contain organic matter, carbon, nitrogen, phosphorus etc. Bat guano is an organic fertilizer that can improve plant growth and soil structure. Mee trees were therefore grown in paddy fields to attract bats in order to collect their guano for fertilizer. Traditional farmers also used the leaves of the tree as fertilizer (Jayatissa, Dissanayake and Perera, 2019).