By Heather Stone, Volunteer-
My inspiration to do this project started in the summer of 2011. I was the designated weed helper for my sister Tiffanie at Compatible Technology International’s plot: Lost Crops of Africa. I’d never done any work in a field before, and my only previous work with plants was growing garden vegetables. The crops were very unfamiliar to me, as were the weeds. The first couple days of going to the field was full of differentiating between weeds and crops. As I got more familiar with the plants, I started asking myself questions. One of the main ones was on the tef that was planted. It was planted in rows, but after a month we could barely get into the crop to weed. Why was the plant so prone to lodging (falling over) and how do farmers in Africa deal with this problem? I started doing research to answer these questions.
Tef is a staple crop grown in Ethiopia, eaten at every meal. The tef seed is so small it’s comparable to sand (there are 1.3 million seeds per pound). The farmers of Ethiopia don’t have any technologies to plant this miniscule seed, so they hand broadcast it, which leads to lodging, inability to weed, harvesting difficulties, a laborious process. I researched ways to plant small seeds, and putting seed in rows always came up as the best way to get the most yield out of a field.
Before I started building a tef seeder, I wanted to be able to compare my seeder with other commercially small grain seeders available for under 100 dollars. There were 5 of them: the Earthway seeder, Vibrating seeder, Dial seeder, Water Bottle seeder and a Push seeder (pictured right in order).
To test these seeders I rolled out a 56cm x 300cm paper roll and laid duct tape (sticky side up) down the center of the paper to catch the seeds as they fell. I then marked 25cm away from the center and also 52cm away. I set a metronome to 72 beats per minute and walked that pace down the paper roll while working the seeding device. Afterwards, I picked 3 different 52cm x 30 cm blocks and counted the seeds in each region (5cm duct tape, 25cm and 52cm). I repeated this for each seeder with 4 trials each and recorded the data. From this test I found out that the water bottle seeder was the best seeder of all those tested, it rarely hit outside of the 25cm mark and the amount of seeds per cm was very reasonable. This was surprising and a little ironic. All of the seeders except the Water Bottle seeder were bought; this seeder I made up on my own, thinking that by dragging the water bottle with holes, it will follow the path you take it on. Since it’s on the ground you won’t have to worry about wind carrying the seed and dispersing them. I then did a field trial on these seeders and my findings confirmed what I’d found in the home trial.
The next thing I did was make standards that I wanted my seeder to live up to. These included: lightweight, easily replicable design, made out of readily available materials, low cost, accurate and has an accepted seed flow rate. I also made a list of materials that would be easily found in third world countries, including: cloth, wood, tires, nails, screws, bottles and cans. Then I went to designing and this is my final result:
Starting with the build; the handle is at about a 45 degree angle made to be pulled. The four (seed holding) water bottles are 4 ½ inches spread apart and are held to the wooden board by screws. There are aluminum slips in-between the wooden board and the caps of the bottles. This controls the flow of seed. On the underside of the board there are furrowing screws (right under the holes seed flow out of), these screws make divots in the ground for seeds to fall into. Because of the tilt to the seeder, the other side covers up the seed. There are also tacks in the wood to help the storing of the seeder, but these are optional.
With my seeder at hand, I tested the seeder the exact same way as the other small seeders with the paper roll method. The seeds never reached the 52 cm marker or the 25 cm marker; it was the most accurate along with having the most consistent seed flow rate.
The next step from here is to test my seeder directly against hand broadcasting. I am currently running tests on which got the most yield in a square foot. I will let you know my findings on my next blog post.
Heather Stone is an 11th grade PSEO student at Century College, a local high school.