The national park closed its gates Saturday to campers and vehicles wanting to pull into their lots for some desert fun -- but because the area is still open to hikers and bikers ... a bunch of Angelenos and others made a mass exodus to the Coachella Valley-area grounds this weekend.

That caused a bit of pandemonium for some of the locals who live right nearby, including 15-year resident Carrie Dagher ... who tells TMZ she's been in full chase-off mode with out-of-town dopes who keep wandering onto her property, apparently thinking it's God's land.

Not the case, according to Carrie ... who says she's literally confronted and driven about 100 different people who unknowingly crossed her front and back yards while exploring the area. Her property and others can stretch anywhere from 1 to 3 acres, so it's understandable a mistaken trespass might happen here and there. That's not the only problem though.

Carrie also tells us some would-be campers have even tried pitching a tent right in her front yard, which she quickly put a stop to as well. Lawn chairs and picnics have also been attempted on her property -- it seems people either don't know or don't care.

The bigger issue, though, is that because of the massive amount of cars coming to the area -- not to mention all the people they're transporting -- Carrie says these bored city-slickers are actually ruining the land with constant traversing, contaminating the rich soil specifically.

BTW, Joshua Tree is far from the only hiking hot spot people want to get to right now -- the Runyon Canyon trail in the heart of L.A. is also drawing hordes of bodies ... most of whom are NOT maintaining any sense of social distancing as they shuffle past each other.

Snitches (or good citizens, really) have been tagging Gov. Gavin Newsom and L.A. Mayor Eric Garcetti to notify them of the bizarre scene, in hopes of getting these public places shut down to avoid further spreading of the coronavirus.