What's up with this vanda leaf?

[Monks-in-Miami]

I noticed this one black leaf earlier this week. The blackening seems to be spreading up the leaf, but otherwise the rest of the plant is healthy. The vanda hangs from a tree where it gets pretty direct sun in the morning, and filtered light for the rest of the day. Any suggestions on how I should treat it? Should I just cut the entire leaf off, or cut just above the black area? Physan? Cinnamon?

Any and all help would be appreciated. Thanks!

[catttan]

Fungus. Cut that leaf off.

[ksriramkumar]

Concur with Yew Sung. Cut the leaf and apply cinnamon powder or sulphur