White crust on philodendron micans leaves
I brought home a new adoptee from Lowe's tonight but one thing has me puzzled. I see that some of the leaves have a white crusty substance on them that look similar to what I imagine salt deposits would look like. It scratches off with my fingernail (I only tried gently doing this on one leaf) and wetting a q-tip and running it over the spots gets a lot of nasty dark crud off the leaves, but the white remains. Is this a fungal infection of some sort and if so, how to treat it? I have another micans that also seems to have some white crust on it.