I have Aronia and i experimented on the bush by forcing it to become a tree like bush, mine is 8 yeas old and is a prolific producer of berries, the trunk is 2.25 inches in diameter and 5 feet high. it is by far the highest producer of Aronia berries than the other Aronia bushes i have that were allowed to go their own way. So i would think Goumi and Autumn Olive could benefit from such training. I also do not know the characteristics of Autumn Olive other than its very good grower in all types of soils to include sandy soil.