The first section of the bill states that it can be called the "Federal Lands Amplified Security for the Homeland (FLASH) Act."

The Table of contents section of the bill lists the titles and sections included in the Act, covering topics like securing federal border lands, reducing environmental harm on public lands, and protecting communities near the border. It outlines specific initiatives and policies, such as creating roads for border security, protecting federal lands from illegal activities, and addressing environmental issues caused by border activities.

The section defines key terms used in the Act, including "appropriate congressional committees," which refers to specific committees in both the House and Senate; "Border State," meaning a state on the southern border; "covered Federal lands," which are specific public lands near the southern border but exclude lands held for Indian Tribes; "operational control," referring to a definition from the Secure Fence Act of 2006; "Secretary concerned," involving the Secretaries of the Interior and Agriculture concerning land management; and "southern border," which is defined as the border between the U.S. and Mexico.

The Savings Clause ensures that this Act does not restrict legal activities like grazing or hunting on federal lands, nor does it affect State or private lands. It also confirms that the Act does not alter treaties or agreements with Indian Tribes.

In this section, the bill proposes building "navigable roads" along Federal border lands to improve border security by allowing access for patrol and emergency response. It outlines requirements for the roads' size, positioning, and completion timeline, and mandates cooperation with the Secretary of Homeland Security for deploying fencing and technology to enhance border enforcement.

The amendment to the Wilderness Act allows U.S. Customs and Border Protection to perform certain activities, such as using vehicles and aircraft, conducting patrols, and building roads in wilderness areas to secure the U.S. borders, while trying to protect the natural character of these areas as much as possible.

The section allows Border States to place temporary structures on certain Federal lands near the southern border without special permission, as long as they notify the responsible Secretary 45 days before placement. These structures can stay for up to one year, with possible 90-day extensions, if approved by the Secretary after consulting with Customs and Border Protection to decide if the border is secure.

The section prohibits the Secretary of the Interior and the Secretary of Agriculture from interfering with the activities of U.S. Customs and Border Protection on federal lands near the southern border. These activities include search and rescue operations and preventing illegal entries, such as terrorists, unauthorized immigrants, terrorist devices, drugs, and other contraband.

The section requires the Secretary concerned to make an agreement with the Secretary of Homeland Security to work together on national security and counterterrorism efforts on federal lands near the U.S. borders, following a specific agreement made in March 2006 or any future versions of it.

The section defines certain terms used in the subtitle, including "applicable fire and sanitation regulations," which refer to specific sections of the Code of Federal Regulations, and "waste," which includes any human-created trash or debris that is left without permission or not placed in a proper receptacle.

The section outlines the requirement for the Secretary, in coordination with the Secretary of Homeland Security, to create and implement strategies within 90 days to reduce environmental damage caused by undocumented immigrants on federal lands near the southern border. It also emphasizes the need to focus on reducing trash, protecting sensitive natural and archaeological sites, and preserving wildlife habitats.

The section requires the Secretary concerned to submit a yearly report to Congress on the amount of trash collected on certain federal lands, mostly where unauthorized immigrants are present or drugs are illegally grown. This report must include details like the total amount of waste, costs of removal, wildlife impacts, and any other relevant information, while ensuring that the privacy of the individuals and organizations providing data is protected.

In this section, any non-citizen without legal status who breaks fire or sanitation rules on certain federal lands can face criminal charges and fines. The fines and penalties will be increased, but they cannot exceed 1 year in jail or $250,000. A report on the fines collected will be given to Congress every year.

This bill section outlines plans for dealing with environmental contamination from illegal cannabis growing on federal lands. It involves the Secretaries of Agriculture and the Interior setting up initiatives to clean up pollution and work with other groups, such as state agencies and nonprofit organizations, under specific guidelines. The section also details funding and legal responsibilities for these efforts.

The amended section of the Federal Insecticide, Fungicide, and Rodenticide Act states that a private applicator who knowingly breaks the law can be fined up to $1,000, imprisoned for up to 30 days, or both. If they commit a federal offense at the same time, they can be imprisoned for up to 10 years in addition to any other penalties.

The section amends a law from 1897, stating that if someone illegally grows cannabis on public lands using unapproved pesticides, they can be fined up to $250,000 or face up to 20 years in prison, or both.

Any person caught growing cannabis illegally on federal land can face a fine up to $250,000, up to 20 years in prison, or both, and these penalties are in addition to other legal consequences they might face. The term "federal land" includes areas managed by the Bureau of Indian Affairs (excluding tribal trust lands), the Bureau of Land Management, the National Park Service, and the U.S. Fish and Wildlife Service.

The Southern Border Fuels Management Initiative is a program set up by the Secretary of the Interior to manage vegetation along the southern border with the aims of reducing wildfire risks and improving safety and operational control. The program involves removing hazardous fuels, controlling invasive species, and installing firebreaks, and it will operate for seven years with $3.66 million allocated annually from 2025 to 2031.

The section requires the Secretary concerned, working with the Secretary of Homeland Security, to create policies to prevent wildland fires and environmental damage caused by people crossing the southern border illegally. It also mandates reports to Congress and the Comptroller General on the effectiveness of these policies and incidents, including details such as the number of fires and environmental damage cases, their costs, and areas affected.

The section defines several terms used in the bill, including "Federal land management agencies," which refers to the National Park Service, Bureau of Land Management, United States Fish and Wildlife Service, and the Forest Service. It also defines "housing" as shelters for certain aliens, and "specified alien" as someone not admitted under the Immigration and Nationality Act.

The section prohibits the use of federal funds to provide housing to certain aliens on any federally managed land. Additionally, it revokes the lease between the U.S. National Park Service and the City of New York for a specific area and prohibits similar leases in the future.

The Secretary of the Interior and the Secretary of Agriculture are required to work together to submit a yearly report to Congress. This report must detail the number of specific immigrants who have received housing on federal land and provide information about their countries of origin.