“ A desolate region is almost entirely without normal vegetation. Local plants are able to unroot themselves and crawl along the ground in search of water and fertile soil. The inhabitants fence their crops in to keep them from wandering off and put heavy stone thresholds in the doorways of their huts to keep wayward plants out.
The plants sense by chemical cues, lacking sight or hearing, and tend to avoid herbivores or anything that smells of 'dead plants'. Characters with horses are likely to be unwelcome among the locals.”
“ An alchemist enchanted his equipment to produce even more powerful alchemical compounds, potions and the like. Unfortunately, it is not well-known that he had different sets of equipment for different processes: If the wrong set of gear is used, the result will invariably fail to function. It's not a cursed item, just something that's hard to figure out.”
“ A Deity of some sort has unleashed a plague of bookworms or something like that in the area. Almost all spellbooks are destroyed, along with bardic and historical books.”