Plant-inspired E-seeds drill themselves into the dirt when moistened
Using drones for aerial seeding may seem like a good idea, but … the seeds could easily just blow away if left on the surface of the soil. A bio-inspired seed carrier has been designed to help, by corkscrewing its seed load down into the ground.
The device is known as the E-seed, and it was created by a Carnegie Mellon University team led by Asst. Prof. Lining Yao. She was in turn inspired by the Erodium genus of plants, which has evolved a unique strategy for surviving in arid climates.
Some of the plants have seeds that are contained within a thin stalk with a tightly-wound tail at the top – that stalk detaches from the main plant and falls to the ground. When it's moistened by rain or high humidity, the stalk unfurls its tail to first prop itself upright and then drill itself and its seed down into the soil.
Yao's E-seed carrier works in the same fashion, although it's made of a moisture-sensitive white oak veneer. It also differs from the Erodium seed stalk in that it has not one but three tails – this feature helps it to get into an upright position on relatively flat soil. Erodium doesn't need as much assistance in that regard, as its stalks typically fall into small crevices.
Although the production of the bio-inspired seed carrier is currently a five-step process which involves chemical washing and mechanical molding, the scientists are working on adapting it for use on an industrial scale. E-seeds could then be dispensed by aerial drones into hard-to-reach places, such as remotely located fields or landslide areas requiring stabilization.
That said, in field tests, the technology has additionally been utilized to deliver non-seed payloads such as fertilizer and nematode worms which kill pest insects.
"Seed burial has been heavily studied for decades in terms of mechanics, physics and materials science, but until now, no one has created an engineering equivalent," said Yao. "The seed carrier research has been particularly rewarding because of its potential social impact. We get excited about things that could have a beneficial effect."
A paper on the research was recently published in the journal Nature.
Source: Carnegie Mellon University