Yeomans’ Plow Company is an Australian family owned and manufacturing company of deep tillage plows.  Yeomans have been manufacturing in Australia since 1954.  The plows we manufacture are designed for deep tillage and renovation of soil.  The models we manufacture range from 6 to 40 foot, with horsepower requirements from 45 to 400 horsepower.  They are used in a wide variety of applications such as vegetable farming, pasture renovation, row cropping, vineyards and the broad acre farmer.  Yeomans has been exporting to the United States of America, South Africa, Asia and New Zealand for many years.  The reasons for soil renovation or subsoiling, is often seen as a costly and time-consuming exercise. Yet there are long-term benefits leading to more sustainable cropping. The prime and fundamental reasons for subsoiling is to increase the fertility and productivity of soil. Increasing fertility is best achieved by converting root matter into molecular humus. Subsoiling mechanically increases the water-holding capacity of soil and increases the oxygen supply to benefit microbiological activity. The abundance of water and air dramatically increases the conversion of all dead soil organic matter into humus, no matter from where it derives. According to Yeomans’ Plow, with all forms of soil building it is especially wise to avoid wasting money on nitrogen-based fertilisers, as the ammonia released by these chemicals kills vitrually all microbiological soil life. Even fully –grown earthworms will die and all soil fertility enhancement attempts will go into reverse. If hardpans have formed in cropping lands, these have to be fractured to allow for the penetration of water and air, and also to allow for the spread of new root fibres into the dead soil material beneath the pan. So how deep? Well, it is always a good approach to rely on commonsense. One depth-determining factor is to subsoil 4 inches beneath a hardpan structure but no more. The cost effectiveness fo the first subsoiling operation will decline with excessive depth. If no classic hardpan has formed in the soil, then a second answer is to cultivate three or four inches below the general existing depth of the pasture root zone. Then there is a third depth determining factor. When subsoiling with a Yemoans or with any subsoiling implement based on the Yeomans design, the appearance of the cultivation lines at shallow depths – just a few inches – look like those of a scarifier or a chisel plow. But with a good  subsolier, as cultiviation depth is increased a point is reached where the appearance of the cultivation completely changes. The earth suddenly appears to simply rise and then drop back in place, all with little apparent disturbance. This becomes a good general minimum depth guide. And the soil life will love it. Deep work to these depths will prevent rain run-off except from extremely heavy downpours. CONTACT DETAILS YEOMANS’ PLOW COMPANY 30 Demand Avenue, ARUNDEL.  4214 Queensland Australia Telephone:  61-7-55716544 Web: www.yeomansplow.com.au Email: info@yeomansplow.com.au Regards Keith Ryan Yeomans’ Plow Company keithryan@primusonline.com.au