shinmai
Chumono
Over the last few days my Natal plum has had leaves turning brown, on the edges at first but then eventually the whole leaf, becoming brittle and falling or easily knocked off. When it started I thought maybe sunburn, because we had a pre-dawn deluge followed by bright, fairly hot sun. I thought perhaps the water droplets were magnifying the bright sun and causing a burn, which I've seen many times on roses. I moved the tree to a shaded/indirect place in the yard, but things seem to be getting worse. Is this possibly a fungus of some kind?