This breed is one of the two traditional breeds of Scotland, having great old names such as : Shepherd's Plaid, Chick Marley
The other Scottish breed being the Scots Dumpy. Both are fairly rare breeds now and the productive strains are virtually non existant. They have been bred almost entirely by exhibtion breeders or others who have not kept records of the egg numbers etc. Without this selection for old fashioned productivity their value as egg layers or table birds is limited. The national flock has lost the qualities that gave the birds such popularity hundreds of years ago.
Our flock comes from a very old line - they are smaller than the large fowl so often seen at shows but certainly larger than the bantams. Old breeders who have seen them say they are more like birds they used to see around farmyards of the past. They are a great fun bird - the boys strutt around the yard like little soldiers and are very proud. The girls are active and pretty good layers. With careful selection they have become strong winter layers, AND great mothers, a rare and useful combination. Both have attractive barred feathering and prefer plenty of space to range in. The eggs are not huge and are tinted in colour.
I have not had the time yet to do much research on this breed and suspect much that is put out there as being wishful thinking. I have concerns that many of the birds I have seen at shows etc are rather soft looking and don't think this is as they probably were.
It is an ancient breed, from at least the 1500s, and was once widely distributed in the area around Lanarkshire, Scotland. It is likely that records of birds around ancient houses; farms and crofts were Scots Greys - so any historians out there doing research on life in olden times in various parts of Scotland, if you come up with references to chickens at all I would love to hear about it.

It may carry both Dorking and Game blood but I can find no more evidence for this so far. They are some of the oldest breeds we have in the UK so its likely. It is a more slender bird than the similarly marked Barred Plymouth Rock, and the barring is not as distinct. The barring on the hen is slightly larger and more clearly defined than that on the cock and the hen is darker. Black mottling is allowed on the white legs.
It is a long-legged, upright standing fowl. Large fowl hens now have a recommended weight of 7-9 pounds and roosters 9-11 pounds. I cannot find any old records yet to confirm this.
The Scots Grey should be a good, year-round layer of large whitish eggs and its flesh is reported to be extremely tasty (but then flavour is mostly to do with rearing and feeding !!). It has a reputation for being a vigorous breed and excellent forager, it was a good choice for a small dual purpose chicken. It is usually a non-sitter, but our strain is a very successful sitting strain without doing too much damage to their annual lay, by compensating in the winter. Our mums are superb !
If anyone has any information about this old breed I would love to hear it - even if it is only anecdotal.
This picture is from a pair of posters we sell depicting a collection of cigarette cards from early in last century. To me it is interesting to see the shape and form of birds then when often the breeds were much more productive.

Scots Grey champion at the Scottish National poultry show 2000
We do not show our birds at all - for a number of reasons
We are simply too far away and too busy
We are selecting for productivity in old strains, not feather and form
We select our eggs at incubation by their correctness for the colour; size for the breed
While we don't breed from birds that are "wrong" for their breed it is health and vigour and egg numbers [or table qualities that interests us more