Apartments, quiet & relaxation when in late 70's. Any advice?

What does the lease say about the use of "common areas"?
What is the noise ordinance in your area? And is there a noise ordinance in your lease? The stricter of the two has to be followed if they are different.
If there is nothing in the lease and there is no ordinance then the landlord is within his rights to place tables and other items where he/she wishes.
Now if it blocks her view to the point where she can no longer see out the window that might be a reason to ask the landlord to move the table. And if the window is designated as an emergency exit there needs to be clearance so that a responder in full gear can still get through the window.

In my Township the "no noise" ordinance is 10pm and after. So check with the Township you live in. If its 11pm u have no recourse but to move. If at 10pm, the landlord has to abide by the ordinance and so do the people in the complex.

I don't think you have recourse if the management clearly stated that noise after 11 pm is not permitted. You can't really expect silence at 5 pm or 6 pm, since that's dinner time and a picnic table is conducive to eating dinner at that spot.

While nobody wants to sleep in headphones, necessarily, you can try soft earplugs if there is significant noise coming from this picnic table that winds up keeping your mom awake past her bedtime. I like sleeping with earplugs, and there isn't any noise I'm trying to silence, either! Try closing the drapes or putting up drapes to muffle any noise coming from that area.

Good luck!

FivePeppers, I can understand that you would prefer a more quiet environment in the evening, but that doesn't always happen when living in an apartment/condo building. It also doesn't always happen when living in a single family home out in the burbs.

One has to think back to when they were young. Bet Mom and friends would have been out at that picnic table if they had lived in that apartment when in their teens or early adults.

Everyone winds down at different times. Where we live [we are also in our 70's] there is Friday Night Football that we can hear [sound carries] from the local high school, the Sports Announcer along with the band music.

Only thing I can think of is maybe move to another apartment in the building, ground floors tend to get more traffic by their windows then upper apartments. But then you may wind up with a neighbor who plays music until midnight.