We think our previous lawn care company got a weed eater too close to the trunk of our 25 year old sago palm (about 3.5 ft tall) and created a large gash in the side of the trunk, a 4"-by-4" area that is about 4" deep, 2-3 inches above the ground. The plant has been suffering since. We have fertilized and we sprayed it with mineral oil-based Volck oil for scale, but it still looks like it is struggling. The leaves are curled up and dried out (brown and dead-looking throughout most of the fronds). We are wondering what we should do about the hole in its side? See attached photo. Thank you for your help.
Certainly the damage could have been caused by such a method.
Damaged trunks can leave the plant susceptible to disease and or pests.
If the trunk is soft, it may not be able to be saved.
I would consult with a professional Arborist that specializes in the care of Palms and Cycads.