Field Notes: Could These Crops Save You Nitrogen?

So let's kick off by exploring the risk processes that occur when we spread urea.

And by risk, I'm talking about those losses because I don't like wasting money.

If you wanna make sure you've pretty well got zero risk of losses, you wanna incorporate that stuff into the soil.

So spread it and then plough it in or drill it straight into the ground.

But if you do that, you are going to get moisture losses and if you're in the cropping game, that's going to cost you.

And if you're in the pasture game, well, if you're ploughing up your paddock, that's probably going to cost you a lot of grazing because you've got no grass left.

So what happens? Well, when we spread urea out on a paddock, moisture dissolves the granule and urease drives hydrolysis towards ammonium.

That is breaking down that pellet and turning it into a form of nitrogen the plant can use.

Surface runoff can, you know, take fertilizer away.

And a rising pH during the hydrolysis process, so making that dirt around the granule more alkaline, can create ammonia gas, which then escapes, and that's called volatilization.

And that is where your biggest losses can occur.

Now, it's not the same risk profile for everyone.

Some people have...

They've got better soil.

They've got higher cation exchange capacity.

They've got different pHs.

And for some people, the risk can be pretty well close to zero of these losses.

But if you're me, I've got some somewhat more acidic soils.

I've got a very low CEC, even though it's pasture country.

That risk is much higher for me.

So that's why that urea was blue.

It had a urease inhibitor coated on it to prevent those volatilization losses.

So what happens when it gets into the ground? Well, when it gets into the ground, it's ammonium.

That's plant available and the plants can use that form of nitrogen.

And it mixes with the exchange sites in the soil and is generally less mobile.

So let's kick off by exploring the risk processes that occur when we spread urea.

And by risk, I'm talking about those losses because I don't like wasting money.

If you wanna make sure you've pretty well got zero risk of losses, you wanna incorporate that stuff into the soil.

So spread it and then plough it in or drill it straight into the ground.

But if you do that, you are going to get moisture losses and if you're in the cropping game, that's going to cost you.

And if you're in the pasture game, well, if you're ploughing up your paddock, that's probably going to cost you a lot of grazing because you've got no grass left.

So what happens? Well, when we spread urea out on a paddock, moisture dissolves the granule and urease drives hydrolysis towards ammonium.

That is breaking down that pellet and turning it into a form of nitrogen the plant can use.

Surface runoff can, you know, take fertilizer away.

And a rising pH during the hydrolysis process, so making that dirt around the granule more alkaline, can create ammonia gas, which then escapes, and that's called volatilization.

And that is where your biggest losses can occur.

Now, it's not the same risk profile for everyone.

Some people have...

They've got better soil.

They've got higher cation exchange capacity.

They've got different pHs.

And for some people, the risk can be pretty well close to zero of these losses.

But if you're me, I've got some somewhat more acidic soils.

I've got a very low CEC, even though it's pasture country.

That risk is much higher for me.

So that's why that urea was blue.

It had a urease inhibitor coated on it to prevent those volatilization losses.

So what happens when it gets into the ground? Well, when it gets into the ground, it's ammonium.

That's plant available and the plants can use that form of nitrogen.

And it mixes with the exchange sites in the soil and is generally less mobile.