brown spots on avocado leaves

[sttmike]

the leaves on my avocados are developing brown spots on the top surface with some form of brownish, blackish mites? on the underside.
i've seen this on avocado trees before and they seem to survive, but one of mine (a 4' tall, one year old pollack) has now lost most of its leaves.
i've started spraying neem oil and cutting off some of the leaves that are affected.
appreciate any suggestions for how to manage.

best,

mike

[pineislander]

Hey I spent the 80's in STX and had an avo tree which bore for six months before the last of the crop dropped off. I can't recall if we had seasons but up here in Florida it is not unusual for avocados to drop leaves about this time of year to the extent of being barren and then begin flowering. One year old it might possibly flower if grafted. Maybe compare to other local Pollock trees?
There are others in the Caribbean who might be able to hopefully help.

[spaugh]

The black sooty stuff looks like bug secretion but its hard to tell from the pic for sure. 

[Capt Ram]

If you look closely on the underside of the leaves you will see it's very small insects or there leavings..I've got the same thing going on and will spray when it warms up a little this week

[guadua]

Avocado lace bugs and they can be a real annoyance.

http://edis.ifas.ufl.edu/pdffiles/IN/IN16600.pdf

[sttmike]

thanks for all the replies.

my guess is that avocado lace bug is the problem.  the link provided by guadua (thank you!) had photos that looked exactly like my plants. 
from the linked article:
''Wolfe et al. (1949) stated that it preferred the West Indian “race” of avocado, although no variety was known to be free from attack.''  which may explain why the damage was most severe on the pollack and less on the adjacent lula and oro negro. 
although an article from the california avocado commission:
(https://www.californiaavocadogrowers.com/cultural-management-library/controlling-damage-caused-avocado-lace-bug) had a different take:
''AVOCADO TREE VARIETIES VARY IN SUSCEPTIBILITY TO AVOCADO LACE BUG.   West Indian x Guatemalan avocado hybrids appear to be particularly resistant to attack.
Hass avocados (a Mexican-Guatemalan hybrid) can be severely damaged by lace bug outbreaks.''

i've just spent an hour or more wandering around the internet looking for solutions.  it appears that there is no real danger to the tree (even with extensive leaf drop) but that it can be a recurring problem season after season.

most suggestions for control start with some form of predator or insecticidal soaps or oils (which seems to have mixed success), or systemic insecticides (imidacloprid) which they say may provide the most effective control, although with some risk to beneficial species.

i guess, for now, i'll just keep spraying the neem oil weekly and see what happens.

really appreciate all the help.  : >)

best,

mike

[OCchris1]

Guadua for the win! Nice job