Using soil moisture for early decisions
Authors: Jane Court and Raquel Waller, Agriculture Victoria
In previous newsletters we have reported on an Enhanced Producer Demonstration Site that is looking at soil moisture probes to predict spring pasture growth. If we can predict a particularly poor (or good) spring season early, what useful decisions could be made that might save money or stress?
Discussions with farmers involved in the demonstrations have indicated that early decision making in spring, could assist with key management decisions such as selling stock early (or purchasing), buying-in feed and timing of pasture sowing in autumn (before too cold) or spring (before moisture limiting) and for summer crops e.g. brassicas (see Laura Forward’s article next).
How did we go?
Pasture growth for spring at all sites – as estimated by pasture cage cuts and silage weights – were within the predicted ranges modelled by Brendan Cullen from Melbourne University on 1 September 2021. This was probably not surprising, however, as all soil moisture profiles were full at the beginning of spring and the probability for a wetter than average spring was forecast for between 65–75 per cent depending on where you were in the state (i.e., higher probability in the east of the state). Therefore, all predictions were for above average (in peak and/or length of spring growth), which was what actually occurred at these sites.
The Bureau of Meteorology (BOM) soil moisture maps have shown to be a good representation of what we are seeing on the ground at the Agriculture Victoria soil probe sites. This is shown in Figure 1, the map of soil moisture (at root zone) as produced by the BOM on 8 February, with the soil probe data (as represented by the coloured “soil cores” on some selected sites).
We held a webinar recently that covered the decision-making topics in more detail, including
- How did we go? – Brendan Cullen, Melbourne University
- Effect of season on stock and feed prices
- What I did – Tim Leeming, farmer and site host
- Critical soil moisture and temperature for pasture sowing – Laura Forward, Meridian Agriculture
If you would like to access the webinar recording, click here https://vimeo.com/711515196
Or contact Jane Court jane.court@agriculture.vic.gov.au.