Q.Ming cutting
My ming is growing tall only with a very thin trunk, but many stems growing near base. What can I do to improve the trunk thickness now supported by poles ? Can I cut the top of plant that is 6 feet tall? How can I get the trunk where cut to grow and will lower plant by base survive if I cut the main tree?
This is a common complaint about Ming plants, they can grow 6 feet or taller.
Dry air, especially in the winter can cause lots of leaf drop. Misting is recommended for this plant.
https://www.gardeningknowhow.com/houseplants/aralia-plants/polyscias-fruticosa-ming-aralia.htm
I have had many people have luck just cutting off the top and keeping in water until it roots. There is no way to thicken the stem or get the bare stem to grow branches or leaves. You can either embrace the plant as is and even trim it further into a topiary or be brave and try to root the top. Good Luck!