Shrub or small tree (6)
I believe this clue is a double definition.
'shrub' is the first definition.
(I've seen this before)
'small tree' is the second definition.
(I've seen this in another clue)
(Other definitions for acacia that I've seen before include "Garden plant also known as wattle" , "Plant of the mimosa family" , "source of gum arabic" , "Plant such as the Australian wattle" , "Spiny shrub with clusters of yellow or white flowers" .)
(Other definitions for juniper that I've seen before include "Evergreen shrub or small tree with berry-like cones" , "Shrub with berries used to flavour gin" , "Shrub flavouring gin" , "Its cones are used to flavour gin" , "Coniferous shrub with berries used to make gin" .)