material (such as rocks, earth, bamboo etc) used to hastily repair a dike / (literary) door bar (vertical bar used to prevent the horizontal movement of a door bolt)
Blob the Builder (建) and Joan of Arc (ji) want to construct (建) a Go (廴) field in the anthill's bathroom (an4), so they paint the field on the floor using decorator's brushes (聿).
tree / wood / coffin / wooden / simple / numb / one of the eight categories of ancient musical instruments 八音[ba1 yin1]
木
=
八
+
十
:
Mnemonic symbol: a Christmas tree. Malte Monkey is putting up a Christmas tree (木) in the bathroom of the space station (Ø4). He's using a cross (十) as a base to put the tree on, and decorates the tree with eight-balls (八).