Putting the (soil) P in productivity

Productivity of cattle is closely tied to the amount of available phosphorus (P) in the soil. Without sufficient soil P, cattle show suppressed feed intake, decreased reproductive performance and significant health challenges.

To help conquer the challenge of low soil P levels which are common across Australia, MLA has launched an updated digital soil map, giving Queensland producers an indication of their on‑farm P levels.

Producers often use supplementation to overcome P deficiency. However, with varying P levels across land types on property, it can be difficult to determine if there’s a deficiency before the severe clinical signs are present. 

Many rely on soil maps to inform them of the likely P status of their lands – while these are a significant decision‑making tool, up to now the information for North Queensland has been missing, leaving a significant portion of the state’s grazing land P status unmapped. 

Mapping for success

Dr Evan Thomas from the Queensland Department of Environment, Tourism, Science and Innovation said producers often develop a P management plan. This involves supplementing P in the form of loose licks, liquid supplements, blocks or via water medication. 

“Without an understanding of what’s likely in your soil, you risk taking the wrong management approach and may not get the expected benefits,” Evan said.

 “The new digital soil map takes all the best available information about soil P levels, and in collaboration with producers collecting additional soil samples, provides indicative estimates of P levels down to a 30‑metre grid space.

“The new digital soil map takes all the best available information about soil P levels...and provides indicative estimates of  P levels down to a 30-metre grid space.”

The map provides general information to producers regarding soil P status across their properties. While it’s a useful indicator of phosphorus levels, producers should still use a combination of soil samples, blood and faecal testing.

“We still recommend soil testing as an essential part of developing a P management plan, with the map helping producers target their actions where supplementation or additional testing might be best undertaken,” Evan said.  

Starting to supplement

Creating the right supplementation program is crucial once a P deficiency has been identified.

MLA Beef Productivity Project Manager, Ainsley Smith, said production goals, cost per unit and quality should all be considered when choosing the best method.

 “Supplement feeding can be costly, so careful and strategic decision making will help you get the full benefits the first time,” Ainsley said.