Has black mold on the leaves and this white stuff? My Lemon is fine, no signs on it. These are my first citris plants. I bought them for the butterflys to lay eggs on so using poison is out of the question.
What's wrong with my Mandrin Orange tree
AAAAACK. Mealie bugs and sooty mold!!
#1. Get rid of the ants! They are probably living in the soil at the base of the tree, under the soil. Sprinkle Sevin around the tree trunk so the ant have to go thru it to get to the nest. Then, I would hit all that fuzzy white stuff with a good jet of water (mealies hate it). When the water dries...see what is left. Oil soap with suffocate the little $%^@@# and once the honey dew is gone, the sooty mold will dry up and wash away and your plant will be OH so much healthier. It is hard to photosynthesize when covered with it. You might also check for scale and aphids (common companions of mealies, spread by ants and causing sooty mold). I deal with those things 24/7 on our citrus trees and they can hear me coming!!!
;.DDD
Thanks Carol. We just got 3" of rain and ants are everywhere. Will give them a good shot of water and put a potted Milkweed plant by it to take care of any aphids and watch to see what happens.