Geese repellent. There are a couple ways to deter unwanted geese. One of them is with a product such as Flight Control. This liquid application does a couple things to discourage geese. It changes the ultraviolet reflection of the turf to mimic a darkened area. The geese will not want to land on what they see as a “dark” zone. It also changes the “flavor” of the grass to make the turf more unappealing to geese. See lawn renovation to establish turf.
These migratory birds can be a real nuisance. Damaging turf from grazing and from their droppings. They can also be a threat when nesting. Geese can become aggressive when protecting their eggs. The male goose can weight in excess of 23 pounds.
Other simple methods include fireworks to scare them from nesting. A laser to scare them in the water. A gird of fishing line over the body of water. There are also agencies which can trap and relocate the geese.
There are other methods, but these are the simplest and most humane. Migratory birds are federally protected. Therefore to avoid any legal issues always check with your local wildlife authority before performing any of these task.