What happens to national parks and federal land inside Texas?

Very little, because the federal footprint on Texas land is unusually small to begin with. Texas kept its own land when it joined the union, so the federal government owns less of Texas than it does of almost any western state, and the parks Texans love stay open through a routine transition.

Texas owns Texas, by design

This starts with a fact most people do not know. When Texas joined the union in 1845, it kept its public lands instead of ceding them to the federal government, which is what most other states did. The result is that the federal government owns only a small slice of Texas, on the order of 1.8 to 2 percent of the state, a tiny share next to states like Nevada or Utah where Washington owns most of the ground. The land question in Texas is small precisely because Texans never handed their land away.

The famous parks are a short list, and they stay open

Texas has two national parks, Big Bend and Guadalupe Mountains, along with national seashores and preserves like Padre Island and the Big Thicket, all run by the National Park Service. Nobody benefits from closing a beloved park, and an independent Texas would keep them open. The standard menu for any federal site applies: transfer to Texas, a cooperative agreement, or continued joint operation. The most natural outcome is that these lands pass to Texas stewardship, most likely under Texas Parks and Wildlife, which already manages a state park system bigger than the federal footprint. Big Bend does not close because the flag changes. It gets a Texas steward.

Most of Texas land is already in Texan and private hands

Because the federal share is so small, the overwhelming majority of land in Texas is already private property, state land, or local public land, none of which is affected by independence at all. Your ranch, your home, your county park, your state park: ownership of all of it is settled under Texas law today and stays exactly where it is. The transition touches only the narrow federal sliver, not the land Texans actually live and work on.

The federal sliver is settled at the negotiating table

The small amount of genuinely federal land, the parks, a handful of installations, scattered federal facilities, gets handled the way every modern separation handles such property: by negotiation. Some transfers to Texas, some is leased, some is settled as part of the larger accounting between Texas and Washington. It is a line item in a negotiation where Texas brings far larger claims of its own, not a fire sale and not a seizure.

Self-government means Texans steward Texas land

The deeper point is about who decides. Today, land-use and conservation rules for federal acreage in Texas are set in Washington. After independence, the stewardship of every acre inside Texas answers to Texans. The parks, the wildlife, the public lands, all of it would be managed by people accountable to the Texans who use and treasure them, not by an agency a thousand miles away.

The bottom line

Federal land is a small fraction of Texas because Texas kept its own land at the start. The national parks stay open under Texas stewardship, the private and state land that makes up almost all of Texas is untouched, and the narrow federal sliver is settled at the negotiating table.