MOST grain growers don't hesitate to assess paddock soil fertility and to correct deficiencies with fertiliser at sowing, pre-sowing or in-crop.
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Averaged across NSW (and the whole of Australia) fertiliser represents the highest crop input cost. That's recognition profitable cropping requires high soil fertility.
Yet commonly we don't address soil fertility in pastures, often on the same property where big dollars are spent on crop fertilisers.
The logic seems to suggest it's not profitable to fertilise pastures, but it is profitable to fertilise crops.
Many colleagues and I, who have been involved in pasture as well as crop research for much of our professional lives, have repeatedly noted pastures responded to correction of soil fertility deficiencies just as much as crops.
Not only have we commonly recorded big responses to modest rates of fertiliser, sometimes in the order of several hundred per cent, but it's equally important to better feed quality.
I often tell prospective new property buyers with an interest in running livestock enterprises that if they don't correct soil deficiencies, they will run them at less than half their capacity.
While fertiliser is a big cost many farms are hardly going to be economic grazing ones unless deficiencies are addressed.
Our property is a case in point. Soil type is light to loam with phosphorus and sulphur deficiency in its natural state so low that legumes fail to thrive.
And if legumes don't thrive soil nitrogen is also low. Correct phosphorus and sulphur deficiency with single super (100 kilograms a hectare) combined with acid soil tolerant legumes within tropical, as well as native perennial grass paddocks, and production multiplies 700pc.
For plants, pasture or crop, correcting soil deficiencies like sulphur and phosphorus also results in deeper and wider roots accessing moisture as well as nutrients over a more extensive area.
Fertilised pastures commonly grow longer into a dry period as well as faster once a season breaks after a long dry period.
Pasture fertiliser programs for many situations are nowhere near as expensive as they are for crops businesses.
Provided legumes are a strong part of the pasture they are capable of supplying, much if not all of the pastures nitrogen requirements.
Meat and wool sales result in far less nutrient export than does tonnes of grain a hectare. In addition, nutrients added via fertiliser are capable of accumulating, at least to some degree, should a drought follow application.
In research we have commonly noted good pasture responses to fertiliser in the year following application if the year of application was a drought.
While residual benefit of fertiliser applied to pasture declines in time (rate of decline depends on many factors) research has commonly noted good pasture responses up to several years after application.
It is not uncommon for good soil nutrient build up to occur from a regular fertiliser program.
As for the economics, our example is a case in point. If we didn't fertilise we would be restricted in livestock enterprise choice and probably would have been in big trouble with the current drought (spring summer).
But fertilised pastures permit a finishing business that largely has allowed for turnoff of finished steers with good growth rates.
Our property, as an example and after decades of research and working with farmers correcting pasture deficiencies, is an essential part of a well-managed business.
Next week. Research supports closer crop row spacing.
Bob Freebairn is an agricultural consultant based at Coonabarabran.
