Variable rate N

[CORK]

Hi all,

I’d like to hear what people’s experiences have been like with variable rate N.
I’ve been looking at the Yara Atfarm system and it looks quite accessible for the likes of me (not into too much tech and not farming 1000’s of acres).
I’m not looking at this because of the current N prices, more so looking to get more out of our crops.

 

[jack6480]

if your lucky you might get one for Christmas

 

[CORK]

looking at this thread doesn’t fill me with confidence….!

No Satellite Biomass Imagery Available This Year for VRA N?

We have not had a useable satellite image since late January so are unable to do any up to date VRA N plans. Given that all these services supposedly use the same satellites, is everyone else in the same boat or am i incredibly unlucky that each of the subsequent ~ 8 passes (approx 1 per week)...

thefarmingforum.co.uk

 

[Brisel]

It works well in oilseed rape canopy management, but largely useless in cereals. That’s 8 years of trials using satellite, drone and N Sensors. @PSQ is pretty adept at using this technology.

 

[CORK]

It works well in oilseed rape canopy management, but largely useless in cereals. That’s 8 years of trials using satellite, drone and N Sensors. @PSQ is pretty adept at using this technology.

Thank you.

When you say useless - do you mean no yield advantage or N saving or useless because of cloud cover?

 

[quattro]

It works well in oilseed rape canopy management, but largely useless in cereals. That’s 8 years of trials using satellite, drone and N Sensors. @PSQ is pretty adept at using this technology.

How are you enjoying working in n Yorkshire??

 

[PSQ]

It works well in oilseed rape canopy management, but largely useless in cereals. That’s 8 years of trials using satellite, drone and N Sensors. @PSQ is pretty adept at using this technology.

I used VRN for a few years but gave up after changing to liquid.
I still pay for the NDVI satellite images, but only to check for areas of high and low variation as a sort of litmus test for further investigation (see avatar).
And we still use the NDVI seed rate maps that we made in 2014, no more insufferable thin bits to stare at all year long.

 

[Brisel]

Thank you.

When you say useless - do you mean no yield advantage or N saving or useless because of cloud cover?

No significant yield response

 

[Brisel]

How are you enjoying working in n Yorkshire??

It’s all good thanks. A different mindset - you get on with it when the conditions are good, ignoring the calendar. If you don’t start drilling in early September, you don’t get it all done before the winter closes in. None of this southern “leave the drill in the shed until October“ Some good yields up here and some very talented farmers too.

 

[warksfarmer]

Hi all,

I’d like to hear what people’s experiences have been like with variable rate N.
I’ve been looking at the Yara Atfarm system and it looks quite accessible for the likes of me (not into too much tech and not farming 1000’s of acres).
I’m not looking at this because of the current N prices, more so looking to get more out of our crops.

Waste of money. Tried real time sensing and sat maps. Neither showed any benefit and in fact real time sensing lowered yield at the time but that was about 12 yrs ago so tech might of changed.
However the real problem is there’s no spreading machines that can vary rate every 1m. So for example on a 24m boom for this tech to work you need to be able to have different rates every 1m length of the boom.
If your sensor is mapping say 6m in front of the tractor you then apply that rate over 24m. If the 6m of crop reads ‘good’ then it cuts rate back on the rest of the 24m which might be ‘bad’.

225kg N for group 1 and 180kg N for feed is a much simpler life and cheaper!

 

[CORK]

Waste of money. Tried real time sensing and sat maps. Neither showed any benefit and in fact real time sensing lowered yield at the time but that was about 12 yrs ago so tech might of changed.
However the real problem is there’s no spreading machines that can vary rate every 1m. So for example on a 24m boom for this tech to work you need to be able to have different rates every 1m length of the boom.
If your sensor is mapping say 6m in front of the tractor you then apply that rate over 24m. If the 6m of crop reads ‘good’ then it cuts rate back on the rest of the 24m which might be ‘bad’.

225kg N for group 1 and 180kg N for feed is a much simpler life and cheaper!

Thanks for this. I don’t think I’ll be bothering!

 

[T C]

How hard can you be on OSR, I know we should have a LAI of 3 to 4 at flowering.
Many crops will have that now.

 

[ajd132]

I haven’t done it but re visit the idea every few years and come to the same conclusion as many of those on here.

 

[Hindsight]

Good explanations and reviews in this AHDB commissioned research. Paid for by your levy.

 

[ajd132]

Good explanations and reviews in this AHDB commissioned research. Paid for by your levy.

I wish they would make this stuff abit more concise for us!

 

[Hindsight]

I wish they would make this stuff abit more concise for us!

All project reports are also present in a concise summary document = which I attach.

But farmers should read the full document. Print it off and read it. As it is full of useful explanations and knowledge and then one gets the full depth of the project, rather than the headline bullet points. AHDB will be disbanded because farmers do not absorb what research work is commissioned. And thus the checks and balance will be removed. But so be it if that is what farmers want.

 

[ajd132]

All project reports are also present in a concise summary document = which I attach.

But farmers should read the full document. Print it off and read it. As it is full of useful explanations and knowledge and then one gets the full depth of the project, rather than the headline bullet points. AHDB will be disbanded because farmers do not absorb what research work is commissioned. And thus the checks and balance will be removed. But so be it if that is what farmers want.

Thanks. Good stuff. Will read this afternoon.

 

[MikeNeaverson]

I've used a couple of systems over the years. In neither was there any noticeable increase in yield and you could do better yourself from the seat just by pressing plus or minus on the rate controller. There was certainly no justification for investing in the kit.

However with fert prices as they are, the cost of over application has increased massively. The economic response curve used to be so flat for so long that as long as you were in the ballpark of N rate you'd be within a few quid of the optimum return. Now that curve drops of very quickly above the optimum N rate and perhaps the software can be more accurate and nuanced than you can be from the cab.

 

[An Gof]

Good explanations and reviews in this AHDB commissioned research. Paid for by your levy.

Can you check that link please, it’s not working here or the summary one. TIA

 

[Phil P]

I’ve tried VR N in the past but couldn’t really see any benefit and we yield map everything. Yes there’s potentially a saving in N if you have bits of crop/field that aren’t worth applying any N too but it’s as easy to just switch off the spreader or drop the rate manually.
By far the biggest benefit I’ve had is VR seed as we have extremely variable soil types across most of our fields. So if you have a consistent crop canopy and good establishment to start with there’s not really any need to use VR N in the first place.