geese hate (become sickened by!) the acid that gives "grapes" there grapey flavor --(the name begins with an a--- but well, i can't possible remember everything)

okay back to my point.. this acid can be, and is used to make things like "grape flavor" kool aid, and other "grape flavor" stuff (candy, icepops, etc.)

but you can take unsweetened grape kool aid mix, mix it with water, and use it to "water" your grass. (get close to the grass, and it will smell grapey!)

it only last a day or two, but unsweetened kool aid is only about 10cents a envelope, so its cheap enough to do it repeatedly.

and if you do, geese will learn not to land, on your property. no geese, no geese droppings..

there are commercially available products that are basiclly the same thing.. (no purple food color!) and they are somewhat effective. but the good news is, cheap, biodegradable, non toxic to plants and animals.. and effective.