Like reeds, grasses, locust? Not sure what size or factor you are thinking. We have lots of trees here growing in the water. Most are out of the water at low tide but several commonly grow in sandbars.
The database below definitely isn't perfect, so I'd verify that any plant on the list you're interested in can handle both submersion and 35ppt salinity (a lot of plants can handle one or the other; relatively few can handle both), but it should be a good place to get some ideas from at least:
Currently, the only non-mangrove/seagrass plant that I've verified can handle submersion and 35 ppt conditions is Sarcocornia perennis - but it grows best at lower salinities and when kept moist rather than submerged (it was submerged at 5cm under the water in the study below, and that was the condition that correlated with the highest mortality rates in the plant).
As a note here, the depth the plant is going to be submerged at under the water is important (as a general rule of thumb, the less water that covers the roots, the better, though are definitely exceptions to this rule; verifying how much water the plant you're interested in can handle is a good idea).
Salinities greater than 35 ppt and completely submerged conditions reduced growth of Sarcocornia perennis (Mill.) A.J. Scott, an important intertidal …