N min tests??

[snipe]

We have had these done in the past but have never had the balls to follow them 100%. Sometimes they say to reduce fert by 50%(100kg/ha total) usually where FYM has been applied. With the Fert price where it is I’m wondering if I should pay more attention to them. Does anyone else follow their recommendations 100%?

 

[Laggard]

How much does the test cost?

 

[snipe]

Agrii a couple of years ago charged £65. I did the sampling my self and took them to lab and it was about £40

 

[Hindsight]

How much does the test cost?

How are you going to interpret the result? Possibly ought to decide that before you take any samples and get those samples tested!

 

[Brisel]

We have had these done in the past but have never had the balls to follow them 100%. Sometimes they say to reduce fert by 50%(100kg/ha total) usually where FYM has been applied. With the Fert price where it is I’m wondering if I should pay more attention to them. Does anyone else follow their recommendations 100%?

Be careful. Just because a lab test says that's what should be available on one day does not mean it's a substitute for extra N throughout. Don't drop below 150 kg/ha N extra applied (unless in extreme circumstances e.g. peat soil) and ignore any reading below 100 kg/ha SMN.

If you really want to know the true value of N min testing, take 3 cores and send them to 3 different labs on 3 different days....!

 

[snipe]

I will mainly rely on my 46year old N sensors

 

[Laggard]

How are you going to interpret the result? Possibly ought to decide that before you take any samples and get those samples tested!

Post the results on TFF and wait for advice. Had a quote from NRM sampling today, anybody used their services?

 

[Gong Farmer]

Soil N is only 60% availability so remember that when interpreting results.

Then throw them in the bin.

Cost of N bought is more important in determining the most cost-effective N dose. At least, this year it is.

 

[ajd132]

I’ve always been to led to believe than N min sampling is basically a waste of time?

 

[Gong Farmer]

I’ve always been to led to believe than N min sampling is basically a waste of time?

Has a role in looking for extremes but in a typical arable rotation you're unlikely to experience any of those.

 

[teslacoils]

I’ve always been to led to believe than N min sampling is basically a waste of time?

Yes. I think the only real place would be after certain veg that leave large legacy N.

Crop gai is a useful tool for osr nitrogen management though.

 

[snipe]

I was thinking they might be some use if FYM or bio solids had been applied, or would you just use the RB 209 figures and adjust Fert requirements based on that.

 

[teslacoils]

I was thinking they might be some use if FYM or bio solids had been applied, or would you just use the RB 209 figures and adjust Fert requirements based on that.

I did some in the year after spring applied digestate. Was concerned there'd be loads of residual n and my oats would go flat. There wasn't. They didn't.

Tests routinely show 20kg available irrespective of rotation.

 

[Hindsight]

I was thinking they might be some use if FYM or bio solids had been applied, or would you just use the RB 209 figures and adjust Fert requirements based on that.

I did some in the year after spring applied digestate. Was concerned there'd be loads of residual n and my oats would go flat. There wasn't. They didn't.

Tests routinely show 20kg available irrespective of rotation.

Generally most times I have had SMN data presented to me it has led to even more uncertainty and confusion. The top of the N dose response curve is quite flat and one can be some 50 kg N applied iether side of the optimum and still be correct. So the few kg N I see folk tweak rates because of a SMN result always intrigues me.

 

[Stephensonlouis]

Been looking at this a lot over Christmas from what I can work out a chlorophyll meter or sap testing would give much more useful data at a lower cost

 

[snarling bee]

Yes. I think the only real place would be after certain veg that leave large legacy N.

Crop gai is a useful tool for osr nitrogen management though.

Re OSR GAI

Not according to my tramline trial it wasn't! Higher N = higher yield, regardless of GAI. Why hold back a good crop? In these days of CSFB larvae eating lots of N its probably even more irrelevant.

 

[Brisel]

Been looking at this a lot over Christmas from what I can work out a chlorophyll meter or sap testing would give much more useful data at a lower cost

That's better. Because the results have the same value.

 

[Brisel]

Re OSR GAI

Not according to my tramline trial it wasn't! Higher N = higher yield, regardless of GAI. Why hold back a good crop? In these days of CSFB larvae eating lots of N its probably even more irrelevant.

Was there any lodging? Even leaning plants are compromising yield.

 

[snarling bee]

In my trial there was no lodging. I'm not saying that would never be a problem though.

 

[Sprog]

Two n-min tests.
The WOSR follows wheat which had digestate in wheat crop April last year and more on stubble before planting OSR first week in September. Pleased with the way crop looks but too wet to take a photo this morning.
The WW follows maize which had chicken muck and digestate before planting and wheat drilled first week November.
Thought residual n would be good so got agronomist to send samples off before the rain set in last weekend. But having got the results what do I do now?
Throw them in the bin and carry on as normal?
Do more tests in a month’s time? Soil, leaf or saps?