Hello, I am trying to identify this weird "thing" that has appeared on some of my Pieris'. I am not sure if it is a disease, an infestation or mold? Description: A black sooty looking moldy stuff nn my Pieris. It also has white fuzzy deposits on the bottom of the leaves. Any ideas anyone? Looking for any suggestions on what it is and or how to get rid of it. Thanks!
thanks for the photos. This does not appear to be from a fungus. Leave it posted though, we have some good plant experts here and I hope they will chime in soon.
The black soot is probably a fungus called 'sooty mold'. It grows from insect secretion, honeydew. Which likely comes from the bugs in the second pic. The second pic looks like mealybugs, which is a major source of honeydew that causes sooty mold, along with aphids, whiteflies, etc. The sooty mold doesn't harm your plants but the mealybugs will. Get rid of the mealybugs and the sooty mold problem will go away. Simply spaying them off with a water hose with a fair amount of pressure will help. You can google other treatments. http://plantclinic.cornell.edu/FactSheets/sooty/sootymold.htm
i agree with the white things being mealy bugs!! and, i agree with the thought that they have to go! and soon!! plain water won't really do the job (works okay for aphids though) because the mealies latch on well and they lay eggs that stick really well... you can mix rubbing alcohol and water (75/25 respectively) and spray the bugs...do that in either early morning or late in the evening...basically at a time when the full force of the sun is not going to hit the plant. the rubbing alcohol will dissipate and then the sun won't be an issue...it's just that while the stuff is still there, damage could be done to the leaves if they are hit with full sunlight. just spray directly on the bugs and just enough to get a good coating on them. wait a day and rinse the plant down with the hose (plain water) and you'll remove the dead bugs and blast away the sooty mold. retreat, with the rubbing alcohol/water mix, in about 10 days if you see more of the white fluffies...