Acorns appear under trees exclusively in Wild World during the Acorn Festival. They grow on oak trees, the trees which do not produce fruit. Giving certain amounts to Cornimer will result in him giving the player an item of Mushroom Furniture. Acorns, Large Acorns, Round Acorns, and Small Acorns will not rot when they are kept in the player's pockets, unlike turnips. Tom Nook will pay 400 bells for an acorn. However, Cornimer will not accept Rotten Acorns. It is sensible to sell Rotten Acorns to Tom Nook, as he will take them for 2 bells, like any other acorn. It is also smart to send them in letters to villagers. They will treat it like any other gift.
The different types of acorns are:
Acorn
Small Acorn
Round Acorn
Large Acorn- Rotten Acorn
Acorn rewards sorted by amount
5 Acorns: Mush Stool
10 Acorns: Mush End Table
25 Acorns: Mush Lamp
40 Acorns: Mush Chair
60 Acorns: Mush Closet
100 Acorns: Mush Stand
120 Acorns: Mush Table
140 Acorns: Mush TV
170 Acorns: Mush Bed
200 Acorns: Forest Wall
230 Acorns: Forest Floor