N & S value in sewage sludge

[average farmer]

What are people's thoughts on the amount of n and s left for the crop in the spring after a dose of sludge in the back end. Off the top of my head the application rate was 22 tonnes/Hec

I'm wanting to know how much if any sulphur to put on. Crops are ww and osr on strong and light land

 

[Wastexprt]

Did STW give you an analysis of the sludge? It should state S content?

Assuming incorporation soon after application I would suggest 10 - 20 % SO3 available, although light land losses may be greater. I would suggest similar for N.

From the AHDB seminar on S on OSR I would also suggest not skimping on SO3 as it can have yield limiting effects if not available in sufficient quantities.

 

[average farmer]

Did STW give you an analysis of the sludge? It should state S content?

Assuming incorporation soon after application I would suggest 10 - 20 % SO3 available, although light land losses may be greater. I would suggest similar for N.

From the AHDB seminar on S on OSR I would also suggest not skimping on SO3 as it can have yield limiting effects if not available in sufficient quantities.

Thank you, yes I have analysis from STW and work on 20kg/N available to the plant, in the first year just not sure when its available. Osr after a dollop of the stuff always goes into winter looking better but not sure if its the P or the N or a bit of both. I'm a bit unsure about the amounts of S that'll be available to the plant in the spring when it wants it.

I must say in the last few years I've noticed a lot better responce on the lighter land than the strong when applying sludge intended to increase the P levels and wonder If we have been neglecting the importance of sulphur or taking it for granted

 

[Wastexprt]

I think that the value of S is underestimated and with decreasing amounts of S emitted from power stations (94% from 1970 to 2010 of SO2 and a further 50% reduction by 2020) will lead to more requirement (sulphur deposition no more than 10 of crop uptake). There's quite a bit of trials and research work around S at the moment, and for a relatively cheap nutrient isn't worth neglecting in my opinion.

 

[Brisel]

I don't normally go without bagged N+S after sewage cake pre drilling. No need to put too much extra on.