Rhode Island Reds can have both Rose or Single Comb, Reds will also be Darker Mahogany color than a Buckeye and the Rhode Island more is brick shape with a long back.
Buckeyes should have a Pea Comb, Not as dark as a Red and less brick shape and a shorter back.
Pea
The Pea comb is a medium length, low comb, the top of which is marked with three low lengthwise ridges, the center one is slightly higher that the outer ones. The outer ones are either undulated or marked with small rounded serrations. This style comb has many variations that are still referred to as a pea comb.
Rose
A broad comb, nearly flat on top, covered with regular points, and finished with a spike or leader. It varies in length, width, and carriage according to breed.
Single
This comb is a moderately thin, fleshy formation of smooth soft surface texture, firmly attached from the beak along the top of the skull with a strong base. The top portion shows five or six rather deep serrations or distinct points, the middle points being higher than the anterior or posterior, forming a semi-oval when viewed from the side. The comb is always erect and much larger and thicker in males than in females.
Chris
I have 18 pullets and 2 cockerels. Two are RIR pullets and two are Buckeyes. For the life of me, I can't tell the difference, even though I've googled, read and even gone to the local farmer supply store. Right now they are are two days shy of being 12 weeks of age. I spend a lot of time with them especially cause I allow them free range time and I have to keep them safe from eagles/hawks and adult hens , so right now they are the same color, size and yellow footed.
