植根於

植 = 木 + 直 : James II of England (zh) decided to go straight-edge (直), so he buried all his drugs in a hole in the space station's kitchen (Ø2) and, as a sign for his new beginning, plants (植) a Christmas tree (木) on top of it.

根 = 木 + 艮 : Guy Fawkes hates Christmas, so he his especially annoyed when he sees a Christmas tree even in front of the encampment. He takes out his chewing gum, sticks it to the tree's star and pulls it as long as he can to see if he can beat his record. Afterwards he wants to wrap the Christmas tree with the chewing gum.

于 = 亅 + 二 : Mnemonic symbol: prepositions (in, at, on, to, ...) are what glue the sentence together. Honey is as sticky as glue, so I'll represent 于 by a honey jar.

Yu the Great (于) was assigned to repair the electronics of the space station's kitchen (Ø2), but instead he was snacking honey from a honey jar (于). Unfortunately his capacitor (二) got stuck in the honey and now he has to use a crowbar (亅) to lever it out.