In the suburban city we live in, the city looks the other way if no one complains when it comes to certain rules. Like for instance, you can't keep a dead car in your drive way(unless you are repairing it) or backyard, you can't have a dead tree in your front yard for an extended time. You must keep your yard grasses below twelve inches in the summer, except, we know now because we asked, for a pollinator garden. I'm sure there are other rules I don't know about. I'm also sure that in most towns and cities there are rules similar to these.

However, I've never seen these rules enforced unless someone calls in. The city does not have an enforcement squad who inspects the neighborhoods. On my street, my next door neighbor is the street busybody. She called in on me once because of a tree that died in early spring and by mid-June I still hadn't removed it. The city worker told me I had two weeks to remove the tree or they would, for a fee. I explained my tree guy was busy and he said no prob, now he knows it will get done.

So, we asked about the pollinator garden just to be sure.

These kinds of things are highly localized and I would not be surprised if there are municipalities that would have this kind of restriction.

It's usually neighbors complaining vs. the government. My buddy had parents who lived in New Hampshire, a notoriously small-government state. They kept their front yard unmowed for insects and wildlife. Got so many complaints from neighbors they had to register their front yard as an "urban nature preserve" of sorts to get them off their backs.

In some urban and suburban areas, where there aren’t a lot of predators, thick vegetation will harbor pests like mice and rats. I’m not sure if there’s a code against in my town, but I have let certain areas of my back yard get thick, sure enough tons of mice showed up in my sheds and moved indoors, too. Do not recommend.

Canadian here, I let my entire back yard grow wild for 7 years. My neighbor was mad about it "because of ticks" and if the town found out about it, they would have come and mowed it and charged me for the "service" plus a fine.

Americans love rules and regulations. America is big on social structures that allow the common man to enforce rules upon others, giving them a sense of power. See HOAs or middle managers as an example.

In my town we have Neighborhood Services drive around on patrol looking for code violations. I put a chair for free at the end of my driveway for not even 24 hours and received a letter from the city. My town really is just one large HOA.