Susan Riepma farms at Tuturau, on a 400-acre family-owned sheep and beef property that has been in the family for generations. Today, Susan works alongside her son Simon, continuing a proud farming legacy while adapting systems to meet modern challenges.
The farm runs approximately 2,500 ewes and 120 mixed-age cattle. Stock are set stocked during periods of lower pasture growth, then moved into a rotational grazing system as grass growth increases. The focus is on producing quality finished lambs, with the bottom 10 percent sold as store lambs and some stock transferred to another block. Hogget lambing has been discontinued to simplify the system and improve overall efficiency.
Located in Southland, the farm experiences cool winters and strong seasonal growth patterns typical of the region. Soil type and climate play a significant role in pasture performance, requiring careful management to make the most of peak growth periods while maintaining pasture quality year-round.
Californian thistle has been a long-standing challenge on the property. Previous control strategies have included topping and the use of MCPA/broadleaf herbicide mixes. While these approaches provided some suppression, thistles have remained persistent, particularly where timing and follow-up control were difficult to align with the grazing system.
Susan describes the farm as a sustainable, traditional Southland sheep and beef operation, with a strong emphasis on good pasture utilisation and stock performance. The goal is to maintain productive, resilient pastures that support efficient lamb finishing while protecting the long-term health of the farm.
Through the Corteva cali thistle control programme, Susan is looking to significantly reduce thistle pressure and, importantly, develop a clear rotation and system that provides ongoing control rather than short-term fixes. By integrating effective thistle management into the wider farm system, the aim is to improve pasture quality and make grazing management simpler and more predictable.
Outside the farm gate, Susan values time with family and grandchildren and supports her husband’s engineering business—interests that make efficient, well-managed farming systems even more important.
The first application of Tordon PastureBoss went on in March 2025. Follow Susan's progress in photos below.
For expert advice on Californian Thistle control or help tailoring this programme to your farm talk to your Corteva Agriscience Territory Manager or your local PGG Wrightson Technical Representative.
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