Q.My stag horn has been in my pontana tree for about 12 years doing well this year it has black holes in the ball of the stag horn a
nd is looking rather sick and looks like it is going to detach from the tree. I have to others that are healthy I live in the Sunshine Coast I think I have some sort of insect doing the damage but not ants could it be native bees or wasps?
If the plant's base, where the frond branches meet, is black, then the plant is dead. A common staghorn fern that is kept too wet is vulnerable to fungal infection, most often rhizoctonia. The infection causes black spots to develop on the thick, rounded fronds that overlap and hold onto the fern's growing surface. The fungus can spread rapidly into the growing point of the plant, killing it. Reducing water at the first sign of black spots can help control the fungus, and the infection can be treated with a fungicide. Fungicides are available at home and garden centers.