High magnesium soils

[Warnesworth]

What is problem with kieserite?

I don't find it works particularly well, and is expensive. As I say, that's just my experience.

 

[Warnesworth]

It's bloody expensive for a start!

I think where Warnesworth is coming from is that applying a product containing Ca, Mg, P, K etc does not guarantee that that element will be available to the crop. It depends on what is going on with the chemical compound it is delivered in and what else in the soil may be surpressing the processes to make it available. A simple lab test for each macronutrient does not necessarily mean it is going to make much difference to the crop. I've had Olsen P index 0 yielding 11 t/ha of wheat year in year out. Pouring P on as DAP and MAP over the years to build indices to 2+ and cover theoretical offtake did not improve yields any further.

In a brief summation, I'd agree with that.

Can you get enough macronutrients into the plant by foliar tonics? The established RB209 Fertiliser manual would have you believe that you'd flatten the crop under the weight of foliar stuff if that's the only way you choose to deliver it. There's a good profit margin in foliar feeds - none of the registration costs of pesticides & not much in each can either. You can see why the likes of Agrii are selling them hard.

And therein lies the question, bit also the answer. Why is the interest in foliar K rising? Is it perhaps because it works? Especially when peak demand for K (in Wheat) is june/july, when the soil is generally in moisture deficit.

 

[Warnesworth]

Perhaps we should all use Maxi-Phi?

You can use whatever you like, only you can decide if they work for you or not. I spend as much time, if not more, advising on the efficient use of N, P, K, S Ca, and lots of other things I don't sell...

 

[Brisel]

In a brief summation, I'd agree with that.



And therein lies the question, bit also the answer. Why is the interest in foliar K rising? Is it perhaps because it works? Especially when peak demand for K (in Wheat) is june/july, when the soil is generally in moisture deficit.

So why not build the soil levels so plenty is available throughout the soil profile? If the moisture deficit is beyond the roots then K won't be the only problem.

So, how about getting enough calcium or magnesium into the plant even if there appears to be enough in the soil? How do you balance the two when there is so much of one of them present?

 

[Warnesworth]

I’ll see what tissue testing says, though that’s only a snapshot and part of the picture.

So, how else do I get enough magnesium into the plant? Or calcium? Is my problem the inverse of Wobblebox’s or is it more complex than that?

Are you just going to recommend of some of your Maxi Phi products? That's cyncial but trying to navigate the murky path into better soil management which is littered with sales agendae that put me right off!

@Brisel. No you can use what product you like ultimately, I haven't made sales recommendations on this forum yet and I am not going to start now. Magnesium is particularly tricky as I suspect you know. Have you tried epsom salts foliarly? But you need to apply quite a lot to get them to work.
Calcium is another tricky one, and this is going to sound crazy to a man who farms on chalk, but does your soil contain enough available calcium?

 

[Warnesworth]

So why not build the soil levels so plenty is available throughout the soil profile? If the moisture deficit is beyond the roots then K won't be the only problem.

But even when soils have plenty of K it seems that foliar K can help. The plant, for whatever reason, cannot access or supply enough at peak demand.

So, how about getting enough calcium or magnesium into the plant even if there appears to be enough in the soil? How do you balance the two when there is so much of one of them present?

I am not sure you can balance them, just do your best to supply the crop what it needs, when it needs it. From what I have read, and forgive me if i have this wrong, but you are trying to reduce your 'soil intervention' by strip-tilling and working on improving your soil health (whatever that means,but that's a whole new thread). In order to maximise the potential soil health gains and consequent nutrition gains I believe you have to feed the plant to feed the soil. And a nutritionally balanced plant can produce more sugars, which means more is given back to the soil which helps to kick start the system.

 

[Brisel]

What happened to feeding the soil to feed the crop?

 

[Warnesworth]

Balanced nutrition, feed the soil and feed the crop. I think we have been so focused on just feeding the crop via the soil that we have forgotten about feeding the soil. Most soil analyses that I take show the soil is depleted. This is the fascinating thing about what I see every day. Every situation bring about a different response. I just like to query what I observe and try to understand it.

 

[franklin]

But even when soils have plenty of K it seems that foliar K can help. The plant, for whatever reason, cannot access or supply enough at peak demand.

Yes. I would agree with this. Despite all manner of soil tests saying plenty of K, we always find that the plant simply cant take up enough when they start to shift. Even then, I cant get an economic return with foliar K, but seems silly to do all the science and then not apply any.

Could it be that high levels of K actually lock up K? Similarly we are up to 800ppm mag but still see deficiency in the crops. Soil would suggest we have no sulphur, but never see it lacking in the crop.

 

[Cab-over Pete]

Wooaah there @Cab-over Pete
Before we start chucking personal insults around, I am just speaking as I observe, I wasn't suggesting that anyone is offering a poor service, racing around or chucking crap over the hedge. Its only this year that I have actually started testing the ag-lime, and it was due to a suspicion that it's not quite what it's claimed to be. I didn't find one that matched the specification. If you want me to test the quarries that you use, I'd be happy to do so. I think everyone has right to know if what they are being sold isn't whats claimed.
I am not doing down ag-lime, quite the opposite, I recommend a lot of it, ideally in prilled form, for all the reasons mentioned above. If anything I think a major problem with many soils is that they are calcium deficient. I don't sell ag-lime or prilled lime, but I do like products that work effectively and in my opinion prilled lime is more effective in a maintenance situation than ag-lime. Becuase it can be applied much more accurately Simple as.

I beg to differ on your spreading accurately idea, but suffice to say no personal insult was stated or implied.
The last thing we need is another thread spiralling downhill!!!

I will also decline your offer of testing the lime I supply because I occasionally send samples away myself. The last time I did so all the claimed figures were exceeded, some by as much as 34%.

I have had results back occasionally to suggest the sample is struggling to meet spec, but it’s been found to be a blip and normal service resumes next time around, so I think nothing to worry about when most figures are very good.

I always send to an independent lab.

 

[Warnesworth]

Yes. I would agree with this. Despite all manner of soil tests saying plenty of K, we always find that the plant simply cant take up enough when they start to shift. Even then, I cant get an economic return with foliar K, but seems silly to do all the science and then not apply any.

Could it be that high levels of K actually lock up K? Similarly we are up to 800ppm mag but still see deficiency in the crops. Soil would suggest we have no sulphur, but never see it lacking in the crop.

With 800 mg/l of available mg you are almost certainly suffering mg induced potash deficiency and mg induced mg deficiency. Work that one out.
Just because you don't see a deficiency symptom doesn't mean it's not there.
I don't think high levels of K locks itself up, more likely the plant just can't access enough, probably due to SMD.

 

[Coximus]

Why dont people name the poor suppliers? And the good ones. I have posted here about this in the past, Tarmac and Hanson have both supplied samples that were less than half of what they claimed on their spec sheet, and the specs were pretty poor.
Tarmac's sample was almost 60% over 1mm in size.... and 10% 3mm+ only 30% less and of that what passes a 150micron sieve I dont know but, at that spec it was about 1/3 of what it needs to be.
That and the cheek they wanted 19 a tonne for it ex - quarry. In the end I got a ground sample with 80% under 1mm, delivered and spread for 25/tonne (10/ for spreading and 15 for the lime). (I belive it came from derby shire but was excess from a large contracting job, as I onlywanted 15ac doing i had to take what i could, but would not take the utter crap offered by tarmacs sales lady).

THe problem for me is access and topography.... but if their was a good reliable supplier please share!

 

[Coximus]

This is the spec asking at 19/tonne ex quarry. Am I right in thinking this is pretty much total crap?

 

[Cab-over Pete]

Well, it’s not very good, but that’s why I ALWAYS say on here to buy ground lime and not screened lime.

You did the best thing and bought just that in the end.

On the high price, that just sounds like a huge company that can’t be bothered to deal with small jobs. If there is a lime spreading contractor local to you I suspect they can get a better price for you if they are buying thousands of tonnes per year.

I bought 16,500 tonnes off my main calcium lime supplier last year. I rang another one of their quarries yesterday for a price on 80t of mag lime. First they said they didn’t have any and then quoted almost three times what it was last year!! I pulled the celebrity “do you know who I am?” LOL:) line and, lo and behold, common sense prevailed!!!

 

[Coximus]

Well, it’s not very good, but that’s why I ALWAYS say on here to buy ground lime and not screened lime.

You did the best thing and bought just that in the end.

On the high price, that just sounds like a huge company that can’t be bothered to deal with small jobs. If there is a lime spreading contractor local to you I suspect they can get a better price for you if they are buying thousands of tonnes per year.

I bought 16,500 tonnes off my main calcium lime supplier last year. I rang another one of their quarries yesterday for a price on 80t of mag lime. First they said they didn’t have any and then quoted almost three times what it was last year!! I pulled the celebrity “do you know who I am?” LOL:) line and, lo and behold, common sense prevailed!!!

Do you know anyone good in Yorkshire? I need 12ac doing this year with 2t of calcium lime and in 2 years again with 2t of mag lime. Mag is easy as local quarry supplies a top notch product but the calc lime just comes too often as utter crap.

Would screened lime ever work? Or is it just super slow?

 

[Renaultman]

To state the bleeding' obvious, try to avoid Mag Lime, and if the haulage isn't too prohibitive use the finest *ground* Calcium lime you can find.
But then again your pH maps look OK, and the lowest pH areas are lower in Mg, possibly lighter corners of the field?

We're on Magnesium limestone so have similar problems. Interesting thoughts on gypsum, agree that anything you apply has to have more Ca than Mg in it. Also interesting about the S03 we have started using polysulphate instead of MOP and getting as much OM as we can get. FYM, Turkey musk, digestate and compost.
My pet passion so sorry for boring the usuals with it.

 

[mo!]

Do you know anyone good in Yorkshire? I need 12ac doing this year with 2t of calcium lime and in 2 years again with 2t of mag lime. Mag is easy as local quarry supplies a top notch product but the calc lime just comes too often as utter crap.

Would screened lime ever work? Or is it just super slow?

We would use Coning as he's local to us.

 

[Cab-over Pete]

Do you know anyone good in Yorkshire? I need 12ac doing this year with 2t of calcium lime and in 2 years again with 2t of mag lime. Mag is easy as local quarry supplies a top notch product but the calc lime just comes too often as utter crap.

Would screened lime ever work? Or is it just super slow?

Yorkshire is a big place. Another thumbs up for Richard Coning. North Yorkshire you could try Neil Fewlass at Robinson Contract Services, Brandesburton. Martin Hays near Chesterfield would cover South Yorkshire I would imagine.

Screened lime will do a maintenance job but needs to be cheap. It won’t put right very low pH levels though.

 

[bravheart]

A basic bit of of nutritional advice, some areas of these fields look terrible (sorry to be so blunt). You have magnesium levels well in excess of the potash so you are probably experiencing some poor yields. I suspect the crops are probably magnesium deficient as well (I know how crazy that sounds in a soil stuffed full of magnesium but bare with me). Some areas are certainly also calcium deficient and the pH is elevated due to the high magnesium.

just looking my maps again.
Going back to @Wobblebox s maps, am i reading this correctly, you saying a dollop of prilled lime is the only way to cure the situation and he should keep applying said material till he gets pottash readings above magnesium readings, also he has artificially high ph's what else would you recommend for that because prilled lime surely won't cure that.

 

[Warnesworth]

just looking my maps again.
Going back to @Wobblebox s maps, am i reading this correctly, you saying a dollop of prilled lime is the only way to cure the situation and he should keep applying said material till he gets pottash readings above magnesium readings, also he has artificially high ph's what else would you recommend for that because prilled lime surely won't cure that.

In @Wobblebox situation I would not try to build the potash to twice the magnesium level because the magnesium level is too high already. Spending more money on potash fertiliser would not be sensible. Spending money on timely applications on foliar potash and magnesium would. As would spending money on a decent soil test....

No lime will ‘cure’ the high pH, but his soil maybe deficient in calcium, the pH maybe elevated due to low calcium and high magnesium. As I say spend money on a decent soil test. After all, the crop is a reflection of the soil ....