Email features have been reactivated 4/17/24
Weed killer was applied a few months ago and that could also be one of the issues, although it wasn't very close to the tree.
Spiders or spider-mites or webworms.
In soil mixes, 10% peat is great (up to 20%) (by volume).
No decomposable ammendment is likely to improve planting holes for mangos--- way likelier to sicken.