Drought-tolerant rootstocks
Large and small companies are seeking strategies to reduce their water use and impact on the environment and to mitigate risk in drought years.
The Bay of Plenty farm has comfortable pasture cover, good milk production and an abundance of clover when most farmers are drying off.
The Law family, who currently milk 850 cows on a 260ha milking platform, historically farmed conventionally using 150-180kg synthetic nitrogen annually.
However, over the past few years Alan, wife Wendy and sharemilking sons Brandon and Cameron have started making changes that will allow them to farm more sustainably.
They implemented the total replacement therapy programme in October 2019, with phase one targeting an improvement of soil health to establish a strong clover presence. Clover fixes nitrogen naturally so synthetic nitrogen can be reduced dramatically without sacrificing pasture production.
Wyndlea, the 89ha home farm, was given its first whole-farm round of total replacement therapy on October last year, with second and third treatments applied in December 2019 and March 2020. Ten hectares of the 120ha Oriini Farm was also added to the trial area.
Positive results snowballed with each application, particularly when summer drought took hold.
“The home farm has hung on far better than it has in previous drought years; our pasture cover is comfortable, and we haven’t needed to feed any additional PKE,” Alan says.
Milk production reflects the substantial feed available: in early summer 2019 the farm was producing 100kgMS/day more than last season, and in April 2020 the herd was still producing 1.5kgMS/cow/day.
The amount of clover observed in the paddock has also increased exponentially, to around 70%, and the family has been able to reduce their synthetic nitrogen use from 180units/N to 80 units/N in the transition year.
They also felt confident enough to add another 50ha to the treatment area at the Oriini Farm.
With phase one complete the team will now steer the farm toward phase two, which will consider the concept of having the pasture rotation extended to around 50 days.
To prepare for this, they have over-sowed 5kg/ha of a three-clover mix and chicory into the soil to increase diversity in all paddocks, rather than planting individual specialty paddocks.
“We have never seen the farm look like this,” Alan says. “Our farm consultant said our farm has the most cover of all her clients.
“I think a huge potential exists with this exciting programme; the future has new potential for all of us.”
The total replacement therapy team intends to hold a virtual field day at the Law farm to showcase the results of the programme.
