Tree Father planted in North America (4)
I believe the answer is:
upas
'tree' is the definition.
(upas is a species of tree)
'father planted in north america' is the wordplay.
'father' becomes 'pa' (pa can mean dad or father).
'planted in' indicates putting letters inside.
'north america' becomes 'us' (United States. I am not sure about the 'north' bit.).
'pa' put into 'us' is 'UPAS'.
Can you help me to learn more?
(Other definitions for upas that I've seen before include "Tree from Java with poisonous sap" , "Sap used to poison arrows" , "Java tree providing arrow poison" , "Tree yielding poisonous sap" , "Antiar tree of Java" .)