A good soil moisture bank at the start of spring provides some assurance of reasonable spring growth. Whilst much of the state is in this position with moisture to depth, East Gippsland is seeing some extremely dry conditions. 

One of our producer demonstration sites projects that finished up last year, provided confidence that soil moisture could be a good indication of spring growth. August was flagged by some farmers as a good time to consider plans for the season ahead – be it a very good spring as many experienced over the last 2 to 3 years, or a poor one.

Unlike the last few years, the outlook indicates a drier, warmer spring.

In this newsletter, we have provided a snapshot across the state of soil moisture and temperature and recommend you click on the links through the report for sites listed, or access the dashboard (link at the bottom).

While April and May were generally colder and wetter than usual, this has been followed by drier and warmer months since, leading to good pasture growth and stock condition across Victoria, except East Gippsland.

Some of the soil probe site hosts have provided comments about the current season and plans for the season ahead.

Compiled by Jane Court, Dale Boyd and Raquel Waller

The autumn break commenced on a dry profile after perennial pasture depleted moisture reserves during the low rainfall decile summer.

After generally good rains across Victoria in April, a dry May was corrected by a wet start to winter. June was very much above average rainfall north of the divide. July was below average, but total rainfall for winter (month to date) is above average in all regions except Gippsland.

The map shows the full soil moisture profiles for most sites across the state (as would be considered average or 'normal' for the end of winter, except East Gippsland which is very much below). 

Soil moisture probes in Gippsland have been drying since mid winter, due to pasture growth initiated by April rainfall but now plant water use requirements are exceeding rainfall. These areas need rain this month to conserve the low soil moisture reserves or there will be a high reliance on spring rainfall.   

Areas of above average rainfall have been able to build soil moisture through winter which will allow them to approach spring with a full profile, albeit a drier spring outlook.

The perennial pasture at the Bairnsdale site, used soil moisture reserves over summer, leaving the profile dry (20%) and only traces of deep soil moisture at 60-80 cm.

Autumn rains made some improvement to the profile, down to 50 cm.

The dry winter has failed to fill the profile above 70% and is now being depleted (10% in the past month).

Bairnsdale perennial pasture soil moisture graph and key dashboard indicators

Temperature over the last week dropped below what was estimated in our last newsletter (9 to 15 May) for most sites. 

The soil probes are also showing soil temperatures are up to 4 degrees colder than the same time last year. This is declining further with the onset of some recent frosts which we have discussed in a previous newsletter. This is despite the warmer than average air temperatures for July (see the maximum air temperature deciles map for July). 

Sites with adequate soil moisture, may consider earlier applications of winter boosting products this year. Areas with drying soil moisture profiles and low soil temperatures will need follow up rain soon to get dry matter responses.

Frost effect on soil temperature - Harrow site example

Soil temperature is influenced by ambient temperatures, rainfall (soil moisture content) and ground cover. Fluctuations of soil temperature at 10 cm occur daily, depending on the weather.

Frost events in the past month can be seen in the soil temperature graph (with insert highlighting recent weeks) with significant drops in soil temperature with 3 events highlighted.

Soil temperatures are best observed for rolling 7 day trends to buffer extreme weather influences and determine if levels are stable or increasing at this time of year.

Charlie de Fegely, Ararat

Perennial Pasture Systems probe site

This year would have to be one of the best autumn breaks we have seen in many years. The early break provided great winter feed and allowed us the opportunity to carry out some early winter cleaning to control barley and silver grass.

We started lambing in early July and had good cover and the ewes were in ideal condition. The clover content was above average (30-50%) which gave us higher lamb growth rates.

Currently, we have nearly full soil moisture profiles but not too wet which was the case for June. When we compare this year with last year we had major water logging in October and November and the pastures ended up very grassy.  As a result animal performance dropped as did the pasture quality. This forced us to grain finish our lambs in the autumn as they hardly put on any weight during spring.

Going forward we are being told about an impending El Nino but we have a full profile of soil moisture. Even if we have reduced spring rainfall we will maintain pasture quality and finish a large percentage of lambs on pasture. Should rainfall in spring drop, we have the option for some strategic use of nitrogen (urea), if we can get it, to promote more pasture growth.

Our clover content is high and we would not apply nitrogen to those pastures. Our next target will be to balance the number of breeding ewes with the available pasture at the end of the season. We aim to have 3000 kgDM/ha to carry our breeders and keep supplementary feeding to a minimum.

Ross Hanrahan, Balmattum Station

Gecko Clan Landcare soil probe site

The season started off alright in autumn but then got a bit dry. July then got very wet, limiting heavy vehicle access to paddocks.

This restricted the use of nitrogen based fertilisers even though the timing was good from a response perspective. Pasture growth was light coming into winter, so sheep relied on supplemental feeding.

Good pasture growth in August and clover growth has been a stand out. It is growing like crazy.

David Caldwell, Lindenow-Meerlieu 

We had a dry finish to summer and then a fairly good autumn, starting late March, but the tap has turned off since early June.

We have had 22 mm rainfall in the past month (16 mm past week)
Year to date is 241 mm (2023)
Year to date was 552 mm (2022)
Year to date was 243 mm (2019 – previous drought)
Year to date average 380 mm, approximately.

Our soil moisture paddocks are quite short, grazed since 26 July through to 18 August.

It is fair to say they were over-grazed as we were holding stock off lambing and calving paddocks. No recent fertilizer application as rain events have failed to materialize. Last fertiliser application was 150 kg/ha of pasture booster in April.

Feed on offer (FOO) was high in mid May from self sown ryegrass and sown improved species; grazed for 4 weeks and spelled from 26 June to 26 July. Was grazed down to approx. 800 kg/ha FOO and currently being rested.  If rainfall picks up prior to the 1 October, a light application of urea at 70 kg/ha is planned.

Overall the farm currently has depleted FOO coming out of winter and will be looking for a spring on dryland country.

Currently running 13-15 DSE/ha on dryland. We will begin selling down to 12 DSE/ha in mid September. Current trigger point date is set at 15 September.

If the season has not improved this will trigger a sell down of yearling steers earlier than planned and all surplus heifers will go.

If no improvement by 15 November the next trigger is early wean and sell down breeding herd by 10%.

I have been monitoring the soil temperatures which were traditionally low during winter and restricts growth.

Now would be an ideal time to apply fertilizers but with a drying top soil and no rain in the short term, plant available moisture is the limiting factor. Fertilizer that was allocated to that paddock has been applied to spray irrigated area where there will be growth responses.

Management from now will be rainfall dependent but if season improves the application of urea will occur, and potentially a RLEM (red legged earthmite) spray in the first week of October (Timerite date) as populations were higher than previous years following the autumn break this year. If no rain in the next 3 weeks, there will be a commencement of strategic livestock sell off.

The soil probe has provided both a moisture and soil temperature insight. While in the middle of winter it felt moisture would be a major limitation, but it was clear at below 10 degrees that temperature impact was significant.

In more recent weeks, as we have lifted past 10 degrees, moisture has become the major limitation. East Gippsland has felt the effects of lower winter rainfall and colder temperatures.

We are now going to need a decent drop of rain to get this spring going based on current evapotranspiration rates. If this fails we all generally have higher stocking rates than historical so a sharp liquidation will occur, if its not already. Fingers crossed.

Ken and Kym Skews, Ensay

Ken and Kym Skews said while the season is dry, and good rainfall events are needed, they would like to think they will have some kind of spring.

Having ryegrass crops in, they would see the benefit of rainfall for further grazings and fodder. 

‘We have already implemented strategies to manage the current conditions, and are planning to sell our steers at weaner weight rather than keeping them on to feeder weight,’ Ken said. 

They feel well prepared for ongoing dry conditions with good fodder stores and water supplies and intend to maintain their cow numbers.

‘We fed our breeding herd through the 2018-20 drought and at that time the economics stacked up,’ said Kym.

‘However, current market prices and the cost of bringing in fodder will influence this strategy if the dry conditions persist,' she continued.

They have trigger points set for early decision making and will readjust plans as required. Both Ken and Kym believe maintaining good animal nutrition was key to their ability to recover quickly from dry seasonal conditions in the past.

After 2 years of good seasons, they are also conscious of the upcoming fire season and the need to prepare.

The soil moisture monitoring website shows data from Agriculture Victoria soil moisture probe sites as well as a number from other organisations including the Gecko Clan and Perennial Pasture Systems group and Gippsland Agricultural Group.

Both soil moisture and temperature are measured at each site with sensors to depth (recorded hourly and uploaded from the field with the telemetry unit).

The website also provides additional site information on the soil characteristics and plant species.

The new dashboard allows easier and quicker access with an improved search function.

This allows farmers to distinguish between crop types being monitored, pasture and soil types and location rainfall, all of which influence soil moisture data.

There is also a Victorian seasonal outlook for 1 – 3 months and extended into spring.

To access the new website.