Q.Arboricola
Why does my Arboricola have sap flowing out of it?

Certified GKH Gardening Expert
It's not sap. It is honeydew. The plant has either aphids, scale or a similar pest that gives off honeydew. It will drip off the plant like it is sap if it is a bad enough infestation. I would recommend treating the plant with neem oil. This article will help:
https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm
https://www.gardeningknowhow.com/plant-problems/pests/homemade-aphid-control-a-natural-way-to-kill-aphids.htm
https://www.gardeningknowhow.com/plant-problems/pests/scale-bug-how-to-control-plant-scale.htm