2025 DEEP SOIL NITROGEN TEST RESULTS
Recent deep soil Nitrogen test results across the Rural Management Strategies client base have provided some interesting insights into the current state of soil Nitrogen in various regions.
For clients with a long cropping phase, most test results have shown comparatively low levels of soil Nitrogen. This trend could largely be attributed to a series of high-yielding seasons, particularly for western clients, which have significantly depleted soil Nitrogen reserves. Therefore, these clients will need to be applying significant quantities of urea to replace Nitrogen removal from last season, when targeting average yields. In some instances, these soil Nitrogen levels have dropped significantly since last year, highlighting the need for routine deep N soil testing.
Clients with strong pasture phases, generally have significantly greater soil Nitrogen levels. The integration of pastures into their farming systems, has helped in sustaining soil Nitrogen. Furthermore, the amount of Nitrogen removed from these paddocks has been offset by urea applications, particularly late applications which was not utilised due to dry spring conditions. Strong levels of residual Nitrogen coupled with moderate yields in 2024, has resulted in proportionately high levels of soil Nitrogen relative to continuous cropping clients in the western regions.
Canola crops with high yield potential before frosting and unaffected by moisture stress during winter and early spring, have generally retained less Nitrogen compared to paddocks where canola did not achieve a strong yield potential.
The results from pulse crops and brown manure vetches vary significantly, even for the same clients. Time of sowing, soil moisture at sowing and subsequent rainfall, seem to have affected biomass production. Pulse inoculation may have also contributed to these variations. The few paddocks of straight vetch that were cut for hay do not appear to have differed significantly from those that were not cut for hay. This is likely due to overall biomass production, resulting in similar levels of below ground Nitrogen fixed. It should also be acknowledged that there may be additional organic matter which is still to mineralise in brown manure stubbles, due to a relatively dry summer and autumn.
While these observations provide a general overview of the soil Nitrogen levels across the RMS client base, it is important to acknowledge that there are exceptions. There are various factors contributing to the Nitrogen status between farms, blocks and even within paddocks. Thus, it is crucial for each client to consider their unique circumstances.
Ultimately, these deep soil Nitrogen test results emphasise the need for tailored Nitrogen strategies which address the distinct requirements of different farming systems. By staying proactive, clients can ensure the long-term sustainability and productivity of their soils.