Urea or AN for D-D spring crops?

[Andrew K]

Put liquid N and P down the spout at planting - much more efficient and effective, and a lot of crops respond to fresh P even when index is medium. Liquid N with P has some immediately available N, as nitrate, while the ammonium and urea components take time to convert to a plant usable form - immediate and slow release all at same time! And NO run-off.

What would you use for spring barley, 5/14/7 ?

 

[yellow belly]

In the USA they put urea on pre drilling.

In 2013 spring barley yielded over 3t with all N applied in march, no-tilled in April.

Leaching of n needs a lot of heavy rain.

 

[Brisel]

In the USA they put urea on pre drilling.

In 2013 spring barley yielded over 3t with all N applied in march, no-tilled in April.

Leaching of n needs a lot of heavy rain.

Define heavy rain! Over an inch could put most of it just below rooting depth earloy on when it needs it most.

 

[Brisel]

We have been using urea both pre-drilling and top dressing for spring wheat, oats and linseed but I am beginning to wonder if it's the right choice. Spring crops need to get up and grow and under dry conditions the urea can often sit on the surface before being dissolved by the next rainfall. The situation can be even worse where there is a lot of surface residue after a cover crop. It could be weeks before the plants can take up the N..
Any thoughts?

I don't get the perception that urea is so much slower to become available to the plants than AN. On a warm wet April day it is a matter of hours. In a cold March it might be a day or two - the wind will be a bigger delaying factor in application date.

What is your establishment method, Jim? Would a pre drilling pass with the drill and urea down the spout open up the surface a bit, then come back a couple of days later with the drill & seed? I used to do this in Australia - urea down the spout a month pre drilling so we weren't held up at sowing time when every day is critical chasing the moisture. The two bin seed carts just ran one commodity each time, saving a lot of logistics. We were doing the extra cultivation pass anyway.

 

[BFSfertilisers]

What would you use for spring barley, 5/14/7 ?

Hi @Andrew K,
We do a 7-14-7 which may be better - a bit more N.
Regards,
Simon