If a giant spore explosion destroys food then it won't necessarily leave a fungus (ballistomycete) even though the food is presumably being 'eaten' by the spores, and if the explosion leaves a fungus on top of food the food might survive. What should happen:
1) If a spore explosion destroys food on the ground then there's a second chance of it generating a fungus, the chance increasing with the weight of the food destroyed.
2) If a fungus is placed on top of food then the food is definitely eaten, with a chance of the fungus growing large enough that it splits into two, placing the new fungus on an adjacent square.
By Andy:
Heh, talk about a mushroom cloud... this could be really interesting if applicable to butchered meat, as a Feawn-allied player could drop chunks all over the place, summon and somehow detonate a spore, then "Evolve" the resulting roomful of fungus into an army of Wandering Fungii.
On the other hand, those "Wandering Fungus"-type things are so stupid, they're really quite inferior to simply creating Giant Spores or Okhlob Plants (I never dreamed I'd get saved by a salad, but those plants ROCK!!)