Hmm...I like those starvation-idea really !
The indirect reason for the burned fields could be the imperial highway through the domain. Over most parts, the road is paved and makes fast travelling possible. (However, inside the Schwarzforst, the highway isn´t very reliable)
So, during the war, more than one Landsknecht-Army stomped through Sorbria....
Another idea: The people in Sorbria don´t know any common nonhuman races, because the world, Sorbria came from was nearly exclusive dominated by humans. Dwarves and gnomes are known by legends and there are even some fairytales about elves (that differ much from the reality about elves). So, the sorbrians will be more than curious about nonhumans, when they happen to meet one. (Exept dwarves. They will be treated as humans, because they just look like small humans...)
But that does not mean, Sorbria has no nonhuman population. Deep in the Schwarzforst is the home of the "Wichtel", a race of strange, tiny humanoids. The existence of the wichtel is known to the people of Sorbria, but the little people are hardly ever seen and more than one sorbrian thinks the wichtel to just another fairytale. The wichtel themselves avoid humans, because they fear the "giants".
Wichtel are about 15 cm tall and dwell in small caves between roots and crude huts constructed of wood and large (poisenous) mushrooms. They are as intelligent as an averange human, but have a rather primitive lifestile thanks to the fact, that they don´t cast metal themselves, but use goods stolen from human farms.
Wichtel nearly always speak in rhymes and have shrieking, childish voices, that are not overly pleasend to the human ear. Most wichtel are quite peacefull (although they enjoy playing tricks), but there are some spellcasting wichtels, that are extremely evil and try to harm humans where-ever they can. The normal tribal wichtel can become also very nasty when they feel threatened. The culture of the wichtel is very strange for humans and similar races and not much is known about it.
Singing a strange, monotone song and dancing around special mushrooms in circles (at full-moon) seems to be very important for them
The wichtel live in eternal fear of the Black Ranger: The darklord of the domain hates the wichtel, but does not actively hunt them down. In the most cases, Max sees a wichtel, he will shoot at sight - but sometimes he is just satisfied by scaring them.
This is a Wichtel (in original size

)
