Weeding Test Certification is a “qualification” for doing jobs in the world of Chiikawa.

In the world of Chiikawa, there are various jobs like subjugation, but also jobs (part-time work) aimed at collecting various wild grasses and weeding. To take on such a job, a qualification in knowledge of wild grasses is necessary. In one episode, Chiikawa and Hachiware are depicted taking this exam. It's primarily a written test, with Hachiware passing level 5 and Rabbit passing level 3. Upon passing, they receive a license certificate, which can be presented in various situations.