Organic matter financial value

Unquantifiable IMO.

TSP is approx. £315/t or for 460 kg of P2O5. That's £0.68/kg of P2O5. Multiply that by the P2O5 in your compost per tonne and then x the dose rate. Repeat for K2O and MgO and you'll have your £/t for each macro nutrient. Sorry - I don't have any recent MOP prices to get a K value.

Be careful where the supplier's nutrients are quoted as elemental values - these are obviously less than the phosphorous pentoxide or di-potassium oxide values used to measure bagged fertiliser.

I don't normally value the N as the available N is negligible. You ought to reduce the P and K values by the % availability too, though on most soils you should recover most of the P long term. K will leach out unless you're on potash releasing clays, in which case does it have a cash value??

Hassle value = some subsoiling where the heap was and any lost crop if tipped pre harvest.
Organic matter value = priceless

There have been a few threads on the value of compost if you have a search @mountfarm

If its any help, I am carting and spreading (in house) 35t/Ha at a cost of £5-6 tonne. It is probably marginal at that - BUT the benefits this year in crop yield were about 1 t/ha. Long term applications on a block I contract farm have given yield increases of 10 - 25%, with no P & K from a bag, fewer slugs (don't know why) and easier working ground.
You have to make your own mind up. If you are on grade 2/3 land I would definitely consider it. Just make sure there is not too much plastic in it.

snarling bee said:

If its any help, I am carting and spreading (in house) 35t/Ha at a cost of £5-6 tonne. It is probably marginal at that - BUT the benefits this year in crop yield were about 1 t/ha. Long term applications on a block I contract farm have given yield increases of 10 - 25%, with no P & K from a bag, fewer slugs (don't know why) and easier working ground.
You have to make your own mind up. If you are on grade 2/3 land I would definitely consider it. Just make sure there is not too much plastic in it.

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the two pieces of independent research I would look at is firstly the the broad walk trail at rothamstead where they have applied organic manures on one plot and mineral fertiliser on the other
The yield increase is about 6%
This has been continued for nearly a hundred years
The soils look completely different and the rate of application of farmyard manure is way in excess of what you could apply in an nvz
This must be a good estimate of the upper limit of any yield increase
The other piece of evidence is niab tag who have applied compost at Morley
The data is a bit noisy but a few per cent increase in yield may be achievable
Having used compost for a decade I think most people exaggerate its effect
In particular its effect on water holding capacity
Do the math
A hectare of topsoil is weighs approximately 4000 tonnes
You apply 30t/ha of which 40% is water so 18t/ha
Plants get water from subsoil as well which is say 1 m deep so 20000 tonnes of soil
I just don't buy it
Price it up on the value of p and k
I get it delivered for £1/t
Pay more if your happy in fantasy land

I use the the value of the bag fertiliser it saves allowing for transport, spreading etc. if it stacks up to use organic sources of P&K I will use them. The soil benefit from using organic sources I call the X factor because I think it is cannot be valued. Do not ignore the downsides of organic nutrient sources such as compaction, importing weed seeds and the hassle factor.

Morley and Rothamstead have completely different soil to me. We don't normally have a problem with water holding capacity, the complete opposite.
Whatever the weight of soil per Ha is not the point, it is the biological activity and OM within that soil that counts and the soil structure etc etc.
All I know is that one side of a hedge budget 9 t/ha 1st wheat, other side of the hedge budget 11t/ha. Difference is lots of compost over the last 10/12 years.
As far as FYM goes, there have been trials giving yield increases of at least 5% on a long term basis, no doubt also with a NPKSMg saving. 35t/ha FYM is still not very much as a % of soil mass.
As I said compost carted 6 miles and spread is perhaps not economic without the 'x' factor, but I cannot see a long term future arable cropping my heavy land farm without putting something on that doesn't come out of a bag. Digested sewage sludge and/or compost have proved that already after only 1 season of use on parts of the farm. Most high yielding farms are using some sort of OM amendment, so that's where I want to head. Sheds are going up now so that home-made FYM will soon be part of the system.

on our farm, and what we bale and cart the best crops are almost always where the ground has muck. straw we had off someone did 8.5 80x70x2.4 big squares a acre. patch of graham wheat at home light application of muck after osr, 11.5 big squares a acre with plenty of grain to go with it.
So i believe the om can be priceless.