Some citizens have adopted a novel method of increasing Bengaluru’s green cover. They mix soil, seed and fertilizer, make balls from the amalgam, and throw them into fields.
The method, called seed balling, is simple, cost-effective and has high chances of success.
Siddalinga Swamy, a research and development engineer who has been a part of Uttishta Bharatha, an NGO carrying out seed balling since 2015, explained the process to The Observer. “To prepare a seed ball, we require seeds, soil and fertilizer. Normally, we use natural fertilizers like cow dung and cow urine instead of chemical fertilizers like potassium and urea. We get the soil free; a seed costs 5-10 paise; we get 20-25 kg of cow dung for Rs 50. So the manufacturing cost is low.
“You have to get a sapling from a nursery. It could cost between Rs 50 and Rs 200. Planting seeds takes a lot of effort and time, but in seed balling, you can just throw the balls, so there is no need to dig. In one hour, a group of 50-60 people can easily prepare 30,000-35,000 seed balls. The process of making these seed balls is simple. It’s just like making a laddoo. We take some soil, and mix cow dung with it in the ratio of 3:1…. You shouldn’t add too much cow urine or water. The preferred soil is always red soil or clay – what we get around lakes,” Swamy said.
There should be only one seed in a ball. If it is thrown on the day it is prepared, there is no need to remove the moisture content. But if it is to be thrown after a few months, then the moisture needs to be removed because, otherwise, the seed will absorb both the fertilizer and the moisture and germinate before it is thrown.
Seed balls should be dried in the sun for a few hours. They can then be preserved for a year. Because a seed ball contains cow dung, insects won’t be attracted to the seed.
About 70% of the seed balls thrown germinate, Swamy said. The survival rate depends on rain. “We always conduct these (ball-throwing) sessions during the rainy season.”
Prof KJP Reddy of the department of aerospace engineering, Indian Institute of Science, has found a different way of dispersing seeds. He uses drones to scatter seeds.
“It was first done near Gauribidanur, 60 km from Bengaluru, on a 10,000- acre land. If you have inaccessible places like Gauribidanur, you can’t go there and put seeds. So I used drones. You can prepare a map that you can follow. Even the drone will follow that path and keep on seeding. You can monitor it with an onboard camera. It will also map how many seeds have germinated,” the professor said.
About the disadvantage of seed balling, he said: “People put a seed into a handful of mud, and squeeze it into a ball. The mud is supposed to have all the nutrients and is tightly packed around the seed. It becomes like a laddoo. But it doesn’t do the job well always because the ball is so tight that the seed is sometimes not able to break out. We keep the seeds in water for a while before scattering them through drones, so that they are on the verge of germinating when they are thrown.”
Durgesh Agrahari, head of partnerships and projects at Say Trees, which has funded the drone project, said: “The seed ball initiative is new, unique and successful. It is a most cost-effective method and consumes less time too. Drones are not too costly in comparison to the volume of balls dispersed. The cost per seed ball is not more than 50-60 paise or a rupee. The cost is not more than Rs 40-50 per sapling. It is a viable project for large-scale afforestation programmes.”