Scabs around neck area

Last week I noticed Harley had some red sores around his neck and I immediately thought it was the collar as it was quite wide and may have been digging into him. Hes just been on the harness for the week and the sores have scabbed to the size of roughly a 5 pence. You could only notice if you parted the fur but they are lumpy and look a bit dry.
I checked to see if they are anywhere else but rest of coat appears shiny its literally just around the neck area and some on the shoulder area.
What do you guys think it could be and any home remedies to treat it. I've attached a rather rubbish pic of one of them just to give an idea you wouldn't notice to look at it but you can just see lumpy fur with a scab underneath.

Has he been in the garden beth? Sounds like an allergy hun get him checked to be sure at the vet meanwhile bathe the spots in warm salt water this will take the itch out bless him

Thank you for replying so quickly, yes he has been out quite a lot the last few weeks so maybe it is a reaction. I shall see if I can book him in tomorrow

Could be hes brushed against nettles beth bless his wee staffy sox i know its unlikely to be his collar his collar looks comfortable and isnt leather leather is more likely to rub.

Now you mention it Crystal he does do a funny twitchy thing when he sniffs stingy nettles lol and sometimes jumps for no reason maybe its that. shall I just bath with salt water over the weekend and still if no improvement ring vets then?
Also can i put sudo cream on them?

Yes beth bathe in salt water no longer than a couple days id use savlon rather than sudocreme and only in areas harley cant lick

Small update- Bathed with salt water and scabs didn't seem to be healing so popped him to the vets to be on the safe side and they think it may be some sort of mite as I left his flea treatment lapse :S because the one he had before lasted 3 months. 
Hes got steroid cream and wash to dab on and some avocate

Bless bopefully the scabs have healed soon