You will need 3 things:
Barrel (empty) 10 memory
Leaf 10 memory
So first: what you start out with is tint-ing the barrel to a dark-ish brown (also shrink it)
Second step: stack the barrels on top of eachother and keep track of layers
Third step: place the leafs around the top of the wood pillar use the rotater tool to angle the stem at the top barrel it dosent matter about the layering of the leafs for now
Fourth step: place them till you get something like the trees right next to the ones i fully made
(its kinda bad because i already made trees and i wanted to make one just for the tutorial)
(final step)(most simple 2)
take one leaf and find it in the layering and put it to the above section then you will get the stack of barrels or the trunk covered making it more realistic (ik its gimkit but bare with me) if you want the stem not to stick out place it by the blast lines surrounding the leaf
Tips:
keep trunk short
keep leafs as scattered as possible but also in a way it looks nice
(warning it takes up lots of memory depending on how many leafs you place)
Hope this helps! 
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