Your best bet is something repellant & lime is natural. It may/may not work as a stomach poison (like boric acid) but will not keep them away.Also, there are appearance issues. There are household products that will work (ants have a keen sense of smell) but may harm the tree. Your best bet is a pesticide, bait to draw them away or ECOPCOARX-avail. in a spray can is 100% natural, fast-acting, provides a residual & is readily available.
Cayenne.
No
No Ants keep a healthy lifestyle by keeping termite populations low and ants also take scraps away.
To keep away from predators
Just put high fences around trees!!!
Try diatomaceous earth. It is a powder and will keep ants out of electrical devices. It is sold at lawn and garden supply houses. Silicone is the second best choice. place the dust at where the ants will have to cross it to get to the connectors.
There's no evidence that sugar gum trees keep spiders away. Several oils, such as tea tree and citrus, may be able to repel spiders.
Army ants are the name given to several species of aggressive ants. The worker ants produce pheromones to keep army ants marching.
Their extensive root systems hold them up.
No, if anything the Weeping Willow would harm the Ants by the around of Aspirin they produce. But, the answer is no. The Weeping Willow will keep the Ants away on its own. If they still find a way to your Weeping Willow. Use a spray to secure the area.
they have sharp thorns
Because you keep feeding them & providing water & protecting them from the elements. Stop all that & they will go away.