This is primarily because interactions with wildlife are unpredictable and potentially harmful.
Every place has its rules - and reasons - regarding visiting pets (service animals are not pets so do not apply). To give you an idea of what you expect, we give a rundown of considerations for different types of lands below. The general rule though is: when in doubt, find out!
When you do leash up, be sure to follow Leave No Trace principles - especially to pack out dog waste - and observe all rules.
Generally, leashed pets can go where cars can: on roads, in picnic areas and sometimes in campgrounds - but not on trails. There may be exceptions for short treks near Visitor Centers or campgrounds. The parks that are the most accommodating to dogs are Maine’s Acadia National Park and Virginia’s Shenandoah, though several more have nearby kennel options. And of course, mushing is another thing entirely.
Wilderness visitors are welcome to bring leashed pets, but if you plan to travel to wilderness that is inside or adjacent to a national park, of course you will need to follow their regulations. Always remember that dogs can pose problems for wildlife, so keep them under good control.
America has 900 national trails, 30 of which are scenic ones like the legendary Appalachian Trail, Pacific Crest Trail and Continental Divide Trail. In general leashed dogs are welcome on most parts of these trails, except where these trails pass through national or state parks that do not permit them. That being said it takes a very exceptional dog to be able to deal with the conditions that some of these trails require one to, so consider carefully what your dog would truly enjoy.
Leashed dogs are generally permitted on trails in national forests. If you plan to camp, keep your dog inside an enclosed area and keep them quiet.
Some monuments like Colorado's Dinosaur National Monument and New Mexico's White Sands, allow dogs on most trails. But others such as Wyoming Devil's Tower or Utah's Cedar Breaks don’t allow dogs on any trails. You’ll need to find out what the rules are for where you plan to go.
Refuges are distinguished for putting wildlife first. While many don’t allow dogs anywhere, like Maryland’s Blackwater, others like Oklahoma’s Wichita Mountains can be remarkably accommodating. In some places, such as New Mexico’s Bosque del Apache, the regulations depend on the season, so once again you will need to find out.
These places are especially for recreation so dogs are often most welcome here. Some are for boating and fishing, though, so you should still ask ahead of time.
Many national seashores allow dogs on beaches (the southeastern ones are often an exception), but they are seldom allowed on trails. National lakeshores, however, often allow dogs on many trails, especially along the Great Lakes.
These parks are considered hidden gems for hikers with dogs as there are few bans.
Most of the lands managed by the Bureau of Land Management are in Western States. These places are generally less well known, but there are plenty of recreational opportunities for your dog, so they might be worth finding out about.
While the federal lands listed above often have many rules, often state parks are less restrictive when it comes to pets. Sometimes this can be a good alternative when you find out the wildland you were hoping to visit won’t allow your dog to join too.
Big Bend Ranch State Park (Texas). Credit: Dave Hensley, flickr.