John Ayres Lines migrated to Australia in 1852, from Northamptonshire, England, and settled in the Skilly Hills, Clare Valley, where he married Elizabeth Williams.
Greater acreage attracted him to the Pekina Run and he moved his family to an area of 1280 acres in the Tarcowie area, which he named “Byefield”, after his home area in England. His interest in animals and the love of animal breeding led him to, in 1885; register the Gum Hill Merino Stud that today, involves the 5th generation of Lines'.

John's son George Glanville, took over the Stud following the death of John in 1900, and in 1926, when proximity to transport became as issue, George moved the Stud base from “Byefield” to Mt Bryan, in South Australia’s mid north farming area where the local railway could send rams to nearly every state, land from the Canowie Station (Hd Anne) and the base of Gum Hill Mt Bryan (Hd Kingston) was purchased.

The working partnership of GG Lines and Sons was formed when George’s sons Lloyd and Lance became active partners after WWII
In 1959, “Geneseo” Keith, brought challenges in the development of uncleared land as part of the 90 mile dessert, in South East of South Australia, and with that a greater understanding of animal health and nutritional requirements, as well as pasture improvements.

In 2000 “Parraweena”, Keith was added and in 2004 “Byefied”, Tarcowie sold.
Total area farmed within the family structure is now 6882ha, currently running 9000 sheep and 600 head of cattle with the addition of 1200ha being cropped to canola, barley and oats.

George had produced large framed sheep, with robust constitutions that would stand up to the harsh Australian conditions.
With the return to the farm of Lance, an industrial chemist graduate, the question was asked, if farmers measure rain, why not other factors?
This brought about Gum Hill being one of the pioneers of fleece measurement, which was introduced in 1955, but by concentrating on fleece weight alone it soon became apparent that bodyweight and fertility declined and wrinkle increased, so since that time ongoing changes in selection criteria have been used based on economic factors. The main pre-requisite for valuable meaningful objective measurement has been that all animals must have the same opportunity and so since the early days of measurement all sheep have been run in large mobs of the same family.

By attending World Conferences on breeding practices, as well as within Australia, along with following research from places such as Trangie Research Centre the present generation of Gum Hill Stud Masters have kept abreast of ever changing trends,

In 1988 Lance was awarded an Australian Medal in recognition of his contribution to Animal Breeding and the rural industry at large.

In 1959, Glan returned to the farm after completing his education, and has continued this evolving trend of economic performance putting his own personality into the stud. He continues to oversee the operation of both the commercial and stud operations.


Justin started at Mt Bryan in 1990 after 12months in Western Australia , he returned to work alongside both Lance and Glan and is has responsibility for the northern properties

In 2000 Haydn had completed his professional wool classing certificate and returned to take over responsibility for the south east properties.