Until September 2019 we were were using weekly data from the Modis satellite to obtain estimates of pasture growth rates in Kg dry matter/ha/day. Sadly the Western Australian government authorities who provided the service decided to close it down.  Data for the property  is available since Jan 2007. The data to February 2011 is shown below where the weekly pasture growth is shown as a red line and the property rainfall as green columns. Minimum growth occurs in the winter where temperatures are often below zero. The maximum is in Spring and mostly we get an Autumn flush in April-May that in good years allows us to carry stock through the winter with little supplementary feeding.

Total annual pasture growth has ranged  from an average low of 4.1 tonnes per ha in 2009 to 14.5 tonnes per ha in 2010. Its relationship to the local rainfall is shown below. Extrapolating backwards shows that zero growth occurs when the rain falls below an annual total of just over 500mm.  Differences between paddocks are small but the pastures growing on the cenozoic alluvium are consistently higher than those on the other parent material types.

As at April 2016, is heading towards one of the severest droughts since 2005 from when data was first collected.  In the charts below the total accumulated Dry matter (TDM in Kg Dry matter /ha) and the Feed on Offer for the two driest years since 2005 (2005 itself and 2006) are compared to 2010 that was the wettest year in the period and the data to date (April 2016).  Note that the  scales of the charts are different. The current year has the lowest FOO and TDM as at April of any of the other years. The advent of frosts towards the end of April mean will inhibit nay pasture growth even if good rain is received after that time.

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