Animal impact or fire for pasture regeneration?

The second of a three soil health webinars was held today and heard from Dukes Plain in the Brigalow belt and Winona in the NSW central highlands. Both spoke about how they have improved soil health, and in the process increased yield and reduced costs. A feature of the soil health webinars is that some farmers are now aiming for 100% groundcover. You can read these and other case studies here.

A third case study attracted my attention. It said:

‘In areas that aren’t grazed, pastures go to seed and senesce, by which time they are of little use for fattening cattle…. There are only two ways to ensure that grasses remain useful for grazing: animal impact or burning.

“Grasses regenerate readily after burning, but at the cost of loss of organic matter, soil biota and volatile nutrients. Frequent burning degrades the soil. Conversely, brief periods of high pressure grazing consume or knock down the pasture before it goes to seed and senesces. This maintains pasture in a vigorous growing condition.”

Fire will favour some species and select against others, so depending on which are desirable, fire may be preferred or not. But fire may affect water and nutrient cycles and succession (increasing stability of the plant community).

Short-term animal impact that incorporates dead grass into the soil and fertilises with manure can be simulated by offering a reward that induces excitement and is consumed quickly. E.g. supplement, hay or salt. Long lasting rewards don’t spark excitement so the effect is less obvious.

Fire is obviously a great pasture management tool and easier to use on a broad scale, but animal impact that improves soil health and long term pasture condition may be worth a try where time and resources allow. I am not saying that strategic early dry season burns to protect assets aren’t necessary. That’s complimentary if it protects more extensive areas of groundcover elsewhere.