Moss and Swamp make Fern in doodlegod.
Moss+swamp
It is swamp + moss
The easiest way to say this: Weeds+Swamp (Pretty Sure)
air+seaweed=fern
fern = swamp + earth
air+seaweed=fern
grass + fern
Sorry but there is no such thing as an actual red fern. Although you could get a fern and spray-paint it red.
sun
On Alxemy, you would combine fern and earth to make a tree.
Yes. If you breathe in fern to your lungs, you can get Hay Fever and will make Asthma Worse...