OSR and Urea

[Dockers]

Has anyone mixed OSR seed with urea prills and drilled down the the same coulter ? Will it burn/scorch the seedling ? ( drill has two hoppers )

 

[Gong Farmer]

Being as vague as it's possible to be, AN can damage in this way, urea much less likely to. But still possible.

 

[Crabtree]

In 2017 I drilled Prilled urea at 10kg/ha mixed together with OSR at 6kg/ha in single hopper Claydon., no sign of any damage but no sign that it promoted growth compared to a part field with no Urea.
Maybe wasn't high enough rate, but it was a Hutchinson's suggestion at the time.

 

[Brisel]

Paging @ajd132

 

[Brisel]

The Australians put high doses of urea into the airstream with cereal seed without any problems. Would DAP be a better choice?

 

[Steel]

The Australians put high doses of urea into the airstream with cereal seed without any problems. Would DAP be a better choice?

Cereals handle urea much better than Canola. Does not take much urea to wreck Canola germination.

 

[KJM]

Not mixed OSR with urea but have done it often with other ferts. 30Kg of N as AN, DAP or compound has been no problem. Have used 60kg of N as AN with forage rape/stubble turnips without issue. No sign of any damage at ends or corners where drill metering has over applied.

Disk drill on 6inch row spacing. If you are on wider rows it will up your concentration.

Very noticable benefit on direct drilling compared with broadcast fertiliser, less of an improvement on cultivated ground.

 

[Wheatseeker]

The following is an extract from a Kansas State Extension Bulletin. It’s referring to wheat drilling but it explains the principles very well.
“The problem with placing urea-containing fertilizer with the seed is that urea is initially converted to ammonia and may be toxic to plant roots if the wheat seed is placed in direct contact with the fertilizer. Producers may hear of someone who has placed urea in direct seed contact and seemed to have no problems, but there are also many cases where urea-containing N fertilizers have injured the developing seedling and reduced or delayed emergence significantly. The risk of injury is greater in drier soils, at higher soil pH levels, and at higher N rates. High soil pH favors a higher concentration of ammonia as compared to ammonium as urea hydrolyzes. There is significant risk associated with placing urea-containing fertilizers in direct seed contact”.