It is similar to idiom 'shaking in one's boots'. It means that one is very afraid and shaking from fear.
It means that the people were very afraid of something
The people are afraid; that is why they are shivering.
The experience left the greenhorn quaking in his boots.
The leaves are quaking in the wind.
San Francisco was quaking from the earthquake
A quaking aspen tree is a type of poplar tree, it is not a conifer.
boots means a pair,
It is hard to understand the slang used by people now a days. "Knocking boots" with someone refers to engaging in sexual intercourse.
A quaking of the sea.
the quaking of the earth
it means that powerful people get too big for their boots and then get murdered..........sort of
Yes, quaking aspens can be planted in a pot. However, the trees will eventually outgrow it and need to be transferred to the ground.
Boots mean "Ma'gafa'eem" (מגפיים) in Hebrew.