The sooner the better on getting the extra dirt off the roots. Silver maples aren't native to Texas - they are planted by builders because they grow fast (but they die young and usually leave a diseased body).
If I were you and you are keeping these trees now for shade, I'd plant another good quality tree at some distance from each of these two (be sure to follow the DirtDoctor tree planting guide
) and once they are established and growing, then take out the maples.
But as to the silver maples now - removing the dirt on the root flare can be done gently with garden tools and a power nozzle on a hose. And then I'd suggest the sick tree treatment
because even if these trees die or are coming out later, it will improve the site for the next trees you plant. Be sure to visit the Natural Organic Library
- there are lots of tips you'll find useful, and sometimes several entries for the same subject (especially when it comes to tree planting.)