Are you stuck on the browntop treadmill going nowhere?
Shifting Pasture Dominance Away from Browntop by Managing for Diverse Swards
Siobhan Griffin
I struggled for years to understand what Allan Savory meant by “manage for what you want”. Often, we as farmers focus on a symptom and try to manage that instead of looking at how we can change our management to address the root cause of the problem.
Brown top management is a good example. Many sheep and beef farmers have been using severe grazing, mowing low in summer, or set stocking beef cattle at low density to manage sod forming low quality weedy grasses to remove the ineffective thatch which forms at the bottom of a sod bound sward. It sounds logical but the result usually is more of the offending weedy grasses because higher succession grasses and forbs like timothy, lotus, red and white clover, and even ryegrass can be stunted, killed, or prevented from growing with set stocking or severe grazing in the summer. The farmer is like the dog chasing his tail and money has been forfeited on lower animal performance and possibly time and fuel by focusing on the symptom (ineffective thatch) but the problem continues because the problem (the management which browntop is thriving under) has not changed and the farmer does the same thing next year like he has been doing for decades.
Back in the 60’s New Zealand researchers looked at browntop and how to manage this poor-quality low performing grass so prevalent on hill country. It is interesting that they found may years of flying on seed and fertilizer had not reduced the prevalence, but they still suggest you need it. The good news is they do acknowledge that changes to pasture management are the missing piece of the puzzle and can allow farmers to encourage higher succession plants of better quality which will ultimately compete with it.
THE OCCURRENCE OF BROWNTOP, MANAWATU IN THE R. W. BROUGHAM, D. A, GRANT and V. C. GOODALL Grasslands Division, DSIR, Palmerston North
Highlights directly from this work:
- The deductions from this work were that fertilizer inputs or clover over sowing alone we’re not sufficient to obtain marked changes in botanical composition. Such inputs must be associated with changes in farm management practice and especially systems of grazing management.
- there is ample evidence to support Levy’s observations that productivity levels’ from browntop dominant pastures are usually much lower than those from comparable areas or farms where species such as the ryegrasses, white clover, dogstail, and cocksfoot are the main pasture components. Suckling (1960)) for example, in a comparison at Te Awa recorded 8500 kg/ha from pure browntop plots under high fertilizer input, a level of production about one (half to one third that of ryegrass sand cocksfoot
- To conclude, hill farms exist today where, through planned fertilizer practices associated with full utilization grazing techniques such as block grazing, and in extreme cases forms of rotational grazing, high production swards can be created.
Manage for what you want
New Grass in Central Otago being mob grazed in November with ewes and lambs followed by beef at Tinwald Farm. Browntop and dogstail will likely creep in if residuals get low in summer or set stocking is resumed.
More reasons to manage for higher succession pasture diversity are revealed in the study below. Although you may not be able to grow lucerne specifically, forbs and legumes tend to have higher nutrient content along with my favourite grass timothy.
ASPECTS OF THE FEEDING VALUE OF PASTURES M. J. Ulyatt Applied Biochemistry Division Department of Scientific and Industrial Research Palmerston North
Highlights
1) Ryegrass and browntop have the lowest feeding value for sheep
2) An extreme example of declining digestibility is seen with browntop which declines from approximately 30% in early spring to approximately 50% in mid-summer (Lancashire and Ulyatt, 1974).
