Anyone interested in local history or genealogy will at some point come across documents
listing areas of land in A., R., and P., the abbreviations for acres, roods and perches, which
are the units of land measure. Even with all the E.U. regulations, farms are still being sold in
acres rather than hectares. Leases, valuation records and tenant’s lists as well as farms
advertised for sale in the newspapers all include land measurements. Before getting into
any detail it is useful to know that an acre is made up of 4 roods with 40 perches in a rood.
With this little bit of information two or three portions of land can be added together when the
need arises. Confusingly a perch is a unit of length as well as of area and it will become
clear later that the size of an acre is determined by the length of the perch.
The word acre originated from an old English word-aecer, which means an open field. In
early times farmers in England defined an acre as the area which they could plough in a day
with a team of oxen. Of course this amount varied throughout the country due to different
types of land and teams of oxen. An acre can be any shape but it was always more practical
to plough a long narrow strip of land where the team would keep going for some distance
before getting a breather as they turned at the ends. Ploughmen preferred a long furrow
because turning the team was a cumbersome process. This furrow-long became the
furlong, a distance of 220 yards, also equal to 40 perches each of 5½ yards. I am using
perches because they are more commonly known in Ulster but rods (not to be confused with
roods) and poles are different names for the same unit depending on which part of Britain
you are in. They varied in length in earlier times but whatever their length, 160 square
perches made an acre so it was always the length of the perch that determined the size of
the acre. The length of the strip has already been determined and the width was set at 4
perches or 1 chain giving an area of 220 by 22 yards, equal to 4840 square yards. This was
the area limited by statute during the reign of George IV which became known as the statute
or English acre.
Although the statute acre eventually became accepted as the standard measurement of
Ulster farmers it had to compete for generations with two other variations both quite widely
used in Ulster, the larger Irish and the Cunningham acres.
The Irish or plantation acre was, as the name suggests, used in Ireland since Plantation
times but was also the measure used in Yorkshire and regions bordering the Solway Firth.
Its size like the English acre was determined by the length of the perch which was 7 yards
rather than 5½ giving an area 280 by 28 yards, equal to 7840 square yards known as 1 acre
Irish Plantation measure equivalent to 1.62 acres statute.
Although the Cunningham acre is of Scottish origin it is not the same as the old Scottish acre
which was 6150.4 square yards. It was abolished when Imperial measure was adopted in
1824 and English acres were imposed by an Act of Parliament. In area the Cunningham
acre fitted in between the Irish and statute acres and is calculated from a perch measuring
6¼ yards giving an area 750 feet by 75 feet, equal to 6250 square yards or approximately
1.3 acres statute.
Leases dated as early as 1687 can be found in PRONI using Cunningham measure and
although it was used in most parts of Ulster it seems to have been more common towards
the coastal parts of County Down right through into the 20th century. The Irish Plantation
measure also survived in some areas into the 20th century. Some variations of this that one
might come across would be Plantation measure, Irish measure, Irish acres and the Irish
Plantation acres, all there to confuse us.

This page was added on 09/11/2014.

No Comments

Start the ball rolling by posting a comment on this page!

Add a comment about this page

Your email address will not be published.