Stalked Hairy Fairy Cup 
Stalked Orange-peel Fungus 
Stalked puffball-in-aspic 
Stalked scarlet cup 
Star-tipped Reindeer Lichen 
Steccherinum bourdotii 
Steccherinum oreophilum 
Steel blue rozites 
Stem rust 
Stereocaulon ramulosum 
Stereum fasciatum 
Stereum lobatum 
Stereum rameale 
Stereum subtomentosum 
Stereum versicolor 
Sterocaulon vesuvianum 
Stinking Dapperling 
Stinking Earthfan 
Stinky squid 
Stocking Webcap 
Straight-stalked Entoloma 
Strobilurus trullisatus 
Stropharia hardii 
Stubby brittlegill