| Scale on a palm is a terror in Florida. Millions of sago palms have gone to the burn pile. There is a new scale called Asian scale that has infested this year. Unfortunately all the techniques recommended here will not eliminate the scale since it lives in the trunk and roots of the plant. You did not mention the type of palm.
You have killed the scale on the leaves and if you have common scale you are OK, but if it is Asian scale it will return in a couple of weeks as new scale hatches out of the pot.
The Florida Dept of Agriculture does not have a recommendation for destroying the scale, hence the burn pile.
We have found the scale can be eliminated with worm tea. The ceitanese in the worm tea dissolves the skeleton of the scale. Treatment is a concentrated solution (20-1 for OurVitalEarth brand) sprayed three times over the course of a week and then repeated if the scale is not dead. (scrape one off with a fingernail and when crushed will be drown rather than green if dead. Then it is necessary to soak the trunk and the ground (pot) as well to kill what is in the soil.
Hopefully, you have the more common type. BTW worm tea will kill common scale in one spraying. Regular spraying is a great preventative.
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jerry  |