Neem oil cured leaf blight
by Richard Roberts
(Corpus Christi, TX, USA)
I have some lovely Ficus benjamina trees (I live in South Texas) and every now and then most of the new growth leaves shrivel and curl up--but don't die--over the whole tree. Whatever was causing it was too small to see.
I tried many standard insecticides, including the ghastly stinking ones from Ortho, to no effect. I finally bought some neem oil at my local nursery, and lo and behold, it got rid of it forthwith.