We bought a large palm from the garden center and were given 2 other small palms by friends who had heard we were going to buy one! The bought palm has developed large lumps out of each of its fronds and is being eaten away. The ones we were given are now following the same pattern. Something is really damaging the palm. Please advise treatment as our 3 palms are really looking tatty.
It is scale. Neem oil may help. Here is more information: https://www.gardeningknowhow.com/houseplants/palms/sticky-palm-tree-leaves-treatment-for-palm-scale.htm
https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm