How kernel germination artificial by river? ...

Caterpillars?
Answers:    water triggers the inestimable majority of seed to germinate. When wet hits the seed chemical reaction start within the pip and germination occurs.
What are those wooden bits set on the...
Depends on the type of pip and what you mean by artificial by water.

Some seed like corn, bean, pea, etc are drier than they would be easily and soaking in dampen not only help soften the outer shroud but it triggers germination.