Get rid of the termite inspection/poison "vents" and have them moved a bit away.
Quit pruning the trees. (naturally a nice "elmish"/cone shape)
Give them a general fertilizer.
Put sand or soil in small amounts over roots that come up and get whacked by the lawnmower--the grass will grow right through.
Give them a few years and just watch them grow.
When I moved into this location less then 7 years ago the few I left standing were about 3" to 4" in diameter--now they are 1 foot in diameter or so and 35 ft tall.
But I'm hard headed and stubborn so I cultivate the silly things myself and it's the only major source of shade for my newish yard until the Bradford Pears and Magnolia's get a bit larger.
They are the predominate tree around here outside of the Cedars, Persimmon, and down by the spring branch the Birchs.
I just call them the "Southern Elm"--it comes up everywhere--sprouts from the roots readily, and puts seeds everywhere.
The resulting "Gum Balls" are your reward for letting the pesky things grow.
But if you "like 'um"--"grow 'um"
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