The stump-jump plough is a kind of plough

Plough

The plough or plow is a tool used in farming for initial cultivation of soil in preparation for sowing seed or planting. It has been a basic instrument for most of recorded history, and represents one of the major advances in agriculture...

 invented in South Australia

South Australia

South Australia is a state of Australia in the southern central part of the country. It covers some of the most arid parts of the continent; with a total land area of , it is the fourth largest of Australia's six states and two territories.South Australia shares borders with all of the mainland...

 in the late nineteenth century by Richard Bowyer Smith

Richard Bowyer Smith

Richard Bowyer Smith was an Australian inventor.Under R.B. Smith's direction, his brother Clarence Herbert Smith created the first stump-jump plough, entitled the Vixen, in 1876...

 to solve the particular problem of preparing mallee

Mallee (habit)

Mallee is the growth habit of certain eucalypt species that grow with multiple stems springing from an underground lignotuber, usually to a height of no more than ten metres...

 lands for cultivation.

The problem

Mallee

Mallee (biogeographic region)

Mallee, also known as Roe Botanical District, is a biogeographic region in southern Western Australia. Located between the Esperance Plains, Avon Wheatbelt and Coolgardie regions, it has a low, gently undulating topography, a semi-arid mediterranean climate, and extensive Eucalyptus mallee...

 scrub originally covered large parts of southern Australia, and when farmers moved into these areas they found it peculiarly difficult to clear the land. After the trees were cut down, the roots energetically produced regrowth. These young shoots and the old roots could be killed by repeated burning (see below), but the large roots remained in the ground, making it impossible to plough the soil. Grubbing the roots out was a slow and labour-intensive activity, and the problem was seriously hindering agricultural expansion.

In South Australia, land was being offered under the Scrub Act of 1866 to farmers on lease, with the option of purchasing after 21 years at the price of £1 per acre. However, grubbing the scrublands was proving costly, at approximately £2 per acre, and solutions to the problem were desperately sought.

Solutions

The situation had grown so frustrating by 1878 that the South Australian government offered a reward of £200 to anyone who could develop an effective mechanical stump puller; although myriad devices were developed, none proved to be a breakthrough success. Many of these machines were trialled in contests near Gawler

Gawler, South Australia

Gawler is the first country town in the state of South Australia, and is named after the second Governor of the colony of South Australia, George Gawler. It is located north of the centre of the state capital, Adelaide, and is close to the major wine producing district of the Barossa Valley...

 in the same year, but none were as effective as three skilled axemen.

Pending the development of an effective machine, a technique known as mullenizing (after a farmer from Wasleys

Wasleys, South Australia

Wasleys is a hamlet located north west of Gawler, South Australia. Roseworthy College is located around 6 km south of the town. At the 2006 census, Wasleys had a population of 235....

 named Charles Mullens) became popular as a means of clearing the scrub. Mullenizing involved dragging a heavy roller over roughly cleared ground to crush young shoots; the field was then burnt, and a spiked log was run over the ground, and a crop of wheat sown. The next season, the stubble and any mallee regrowth was again burnt, and eventually the mallee died, though stumps remained underground.

Breakthrough

In 1876 a special plough was invented by agricultural machinery apprentice Richard Bowyer Smith

Richard Bowyer Smith

Richard Bowyer Smith was an Australian inventor.Under R.B. Smith's direction, his brother Clarence Herbert Smith created the first stump-jump plough, entitled the Vixen, in 1876...

, and later developed and perfected by his brother, Clarence Herbert Smith

Clarence Herbert Smith

Clarence Herbert Smith was an Australian agriculturalist, engineer, blacksmith and inventor....

, on the Yorke Peninsula

Yorke Peninsula

The Yorke Peninsula is a peninsula located north-west and west of Adelaide in South Australia, Australia, between Spencer Gulf on the west and Gulf St Vincent on the east. It has geographic coordinates of...

 (where the problem was particularly acute). The plough consisted of any number of hinged shares

Ploughshare

A ploughshare or plowshare is a component of a plough or plow.Ploughshare or Plowshare may also refer to:* Operation Plowshare, United States project to use nuclear explosives for civilian purposes* vomer, facial bone in the human skull...

: when the blade encountered an underground obstacle like a mallee stump, it would rise out of the ground. Attached weights forced the blade back into the ground after the root was passed, allowing as much of the ground to be furrowed as possible. Although a little unorthodox, the plough in action appearing "like a ship in a storm", it proved remarkably effective, and was dubbed the "stump-jump" plough.

The invention was hailed as a "complete revolution" and, in combination with the process of mullenizing, was adopted almost universally across the mallee lands, even proving as useful in stony ground as it was in mallee country.