Grass is what covers the player's town (in the areas not covered by buildings, pavement, and dirt). In early December, snow falls and replaces all of the town's grass. On February 25th, the snow melts, and the grass comes back. In September the grass begins to become lighter to turn darker and browner in October and November.
Grass by game
In Animal Crossing, all of the town not occupied by pavement or buildings was filled up with grass. There were only a few spots occupied by dirt, and those were designed in figure 8-like shapes.
In Animal Crossing: Wild World, more of the land was occupied by dirt rather than grass, giving the player's town a more desert-like feel.
In Animal Crossing: City Folk, the player starts out with an almost complete town of grass. However, as the player plays the game, the grass starts to disappear. This process is called grass deterioration, this process only happens in areas where the player walks (and usually walks/runs most often). Grass will wither faster if it is run over rather than walked. However, grass deterioration can be prevented by staying off dirt where the player would like grass to regrow in. This process can take up to a few months until the grass regrows completely.
In Animal Crossing: New Leaf, grass deteriorates the same way as in Animal Crossing: City Folk but at a slower pace. Grass deterioration is NOT prevented by placing a pattern over it. Grass can be regrown over dirt by planting flowers over it, and watering those flowers every day (even if the flowers are not dying) until the grass has regrown completely. Rain and snow will also accelerate grass restoration.
There are three different designs for snow/grass in the Animal Crossing series. The patterns change when grass turns to snow and vice-versa. (The picture below does not apply to Animal Crossing: New Leaf.)
|Undergrowth vegetation||Flower • Grass • Bush • Jacob's Ladder|
|Trees||Bamboo • Money Tree • Stump • Palm • Tree|
|Weeds||Weed • Clover • Rafflesia • Dandelion|
|Other||Grass Deterioration • Fruit • Flower Fest|
|Geography of an Animal Crossing Town|
|Water||River | Ocean | Pond | River Pool | Waterfall | Water System | Bay | Tropical Seas|
|Land||Tree | Palm | Cliff | Ramp | Canyon | Beach | Grass | Grass Deterioration | Island|
|Ramps||Regular Vertical Ramp | Wide Double Ramp | South-East-Facing Straight Ramp | South-East-Facing Angular Ramp | East Cliff Straight Ramp | East Cliff Curver Ramp | Straight South-West Corner Ramp | South-West Corner L-Shaped Ramp | West Cliff Straight Ramp | West Cliff Fold-Back Ramp | South-East Inside Corner Angular Ramp | South-East Inside Corner Normal Ramp | South-West Inside Corner Normal Ramp | South-West Facing Inside Corner Stretched Extremely Wide Very Long Ramp|