How long can roots be submerged

[Orkine]

I survived Irma with almost all my tree in ok to good shape.  I had 6 inches or so of rain last night in Jupiter and it just wont drain (I am speculating hurricane debris is in the culverts somewhere).

My trees are under water, even mounds that are always above water and did not see any inundation during Irma are under water.
 My question is how long before I loose my trees

Mangos
Avocados
Lychee
Mulberry
Jackfruit
Bananas
Citrus (various)
Hog plums
Guava
Dragon fruit.

At least one or more of the listed plants have water over the root ball.

FOLLOW UP:
Will mature trees fare better than recently started trees or are they more at risk due to deeper and more dense roots under water?
 

[AnnonaMangoLord45]

If you grow them in the proper soil, at least 2 weeks, for avocados, you might want to kiss it goodbye after a few days, more importantly, is the water running or stagnant, that affects how much oxygen the plants can pull from the water. Bananas will come back from anything, mangos the same. The ones I'd worry about most would be DragonFruit and avocados, If all else fails, use an injection of Agri Fos to kill whatever diseases form

[Seanny]

Buy the cheapest pump you could find and drain your lot? A sump pump with tubing would work.
Is your street flooding?

[Orkine]

Pumps wont work on this, I have a little more than an acre and a canal that is at the same water level as my yard draining hundreds of acres much of which is just as wet.  No where to pump into, just back into my yard.
It is saturated, so much so the earth worms are dead and floating under some of the trees, so sad.  Started last evening so coming up on 24 hours.  I don't anticipate draining for at least 12 to 24 hours if lucky, maybe more.  This is not typical which is why I am assuming hurricane debris or something atypical blocking regional drainage.

[pineislander]

FOLLOW UP:
Will mature trees fare better than recently started trees or are they more at risk due to deeper and more dense roots under water?

One thing I noticed during recent flooding was that recently started trees have much more problems with flooding than established trees. This could be due to the new trees having roots only in the pot zone whereas established trees have an extensive enough root system which can find some small amount of air here and there in the soil, even if saturated. It might be hit or miss. I had two avocados suffer while many others nearby had no problem. My neighbor had four sugar apples near to each other, only two drowned, the other two seem unaffected. As water receded, they tried digging ditches around those to no avail. Almost all papaya in the neighborhood drowned, I had 20 young 4 ft. trees on mounds and lost none. I noticed that the former owner of the property who was a 30 year veteran planter had everything on mounds so I followed suit and am glad I did.

[Orkine]

Thanks.  The water started receding last night and by the morning, 80 of the trees are on soggy but un-inundated land.
The mounds seemed to help and they were peeking out above the flooding last night and fully out this morning, even the one foot or so appeared to help.  I may make this the standard for any replacement trees.

[greenman62]

Yep
Kenner where i live (outside New Orleans)
was a swamp, and they filled the lots with river sand (30yrs ago)

the water table varies from about 4ft to about 1ft depending on how much rain weve had recently.
large rain events will flood the yard, but usually just for a couple of hours
In Katrina, and 2 or 3 other floods, it lasted a couple of days.

If the water is moving even just a tiny bit, it helps a lot
even a slow rain, and slow-drain keeps water moving.
stagnant water is the real killer.

My guava and my satsuma orange were the only 2 fruit trees i had during Katrina
and both faired OK.
i think the satsuma took a year off from producing, but, it does that sometimes anyway.

the only thing i see on that list that ive lost due to water is Avocado
and ive grown them all except hog plum,

when it dries out, a good compost, or compost tea
(with some kelp, fish etc...)
might be a good idea to get the biology working again.