Sounds like hotspots or a grass allergy - my Lab x gets the same in spring and summer. Dry, sore red, itchy, hairloss...

Cutting out all chemicals worked, giving her two fish oil tabs twice a day did AMAZING things (you can start with a higher dose, it won't hurt her) and the very bland diet of rice, veg and raw meat.

Honestly though, the Fish Oil was like a dream cure.