# Diesel exhaust fluid



## ceral weed killer

Hello,

Been lurking here for awhile, have learned so much!!!!

I was gifted a 55 gallon drum of DEF. Does anyone have any idea how this might be applied? I am sure it has to be diluted but I have no idea where to even start. My only other option is to go and buy a diesel truck.

Thanks for any help I can get.

Oh, I have a Bermuda yard of about 3/4 an acre. IT IS NOT FLAT, but im working on it :lol:


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## Suburban Jungle Life

DEF is 32.5% urea so you can use that number to calculate your # on the ground.


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## Suburban Jungle Life

Sorry. It helps to know it weights 9.09 lbs per gal for your calculations.


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## Suburban Jungle Life

I'm going to try this math. Please don't use it until someone else has confirmed it.
1 gal = 128 fl oz
DEF is 32.5% urea
128 fl oz weighs 9.09 lbs
9.09 * 0.325 = 2.954 lbs of urea per 128 fl oz

urea is 46%N
2.954 * 0.46 = 1.3589 lbs of N per 128 fl oz

1 lbs of N/M
(128*1)/1.3589 = 94 fl oz /M

0.5 lbs of N/M
(128*0.5)/1.3589 = 47 fl oz /M

0.25 lbs of N/M
(128*.25)/1.3589 = 23.5 fl oz /M

Either way, since you are spraying this, it is a more potent mix. Watering it in after is a good idea or if you choose not to, use the 0.25 lbs of N or maybe even less per application. Increase your application frequency to compensate if you want more N. Also, keep in mind, this is just N and you might need some P and K.


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## Spammage

@Suburban Jungle Life not sure your math is correct. I have a 2.5 gallon jug of 21-0-0 that says 15 oz/1000sf= .25 lb of N.

Also, are you guys sure there isn't anything else in the DEF that would be harmful to the soil?


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## Suburban Jungle Life

DEF is urea and de-ionized water.

If you take 32.5% * 46% = 14.95% so DEF would be 15-0-0.

If this is the right calc, it does seem to be comparable with your product. You are using 15 fl oz for 0.25 lb of N and DEF by my calc is 23.5 fl oz since the analysis is lower for N, you need more product for the same 0.25 lb of N.

Does this not seem right?


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## Spammage

Suburban Jungle Life said:


> DEF is urea and de-ionized water.
> 
> If you take 32.5% * 46% = 14.95% so DEF would be 15-0-0.
> 
> If this is the right calc, it does seem to be comparable with your product. You are using 15 fl oz for 0.25 lb of N and DEF by my calc is 23.5 fl oz since the analysis is lower for N, you need more product for the same 0.25 lb of N.
> 
> Does this not seem right?


Interesting that DEF is only Urea and water - learn something new and different every day.

Yes, I originally took your 32.5% number as N and not 46% N, so based on this, your calculations appear to be correct.


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## Suburban Jungle Life

Oh yeah. Sorry. Maybe it wasn't clear. DEF is 32.5% urea but urea is 46% N so that makes it even lower. I do wonder if de-ionized water is a problem. I guess it being a small quantity of the total water plants receive would mean it doesn't matter and wouldn't affect the mineral content available for the turf.


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## dfw_pilot

Spammage said:


> Interesting that DEF is only Urea and water - learn something new and different every day.


+1


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## ceral weed killer

WoW!

Thanks!

I was planning on watering in, depending on mother nature is generally feast or famine it seems. The sprinklers are definitely more controllable.

I am also a fan of lower application rate/more applications. I do not seem to do well with my sprayer or my spreader with just one pass , it just never seems to work out right.

Thanks again and maybe one day I will have pictures worthy of the site.


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## JERSEY

Is anyone else trying this?

Its dirt cheap at walmart for truckers.

I was going to try it with some ferrous sulfate.

i was thinking like 4-6 oz DEF per gallon/1000sqft.....light shot


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## Suburban Jungle Life

JERSEY said:


> Is anyone else trying this?
> 
> Its dirt cheap at walmart for truckers.
> 
> I was going to try it with some ferrous sulfate.
> 
> i was thinking like 4-6 oz DEF per gallon/1000sqft.....light shot


Are you sure it's cheaper than a 50 lbs bag of urea?


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## quadmasta

I think I paid like $20 for a 50 pound bag of prilled urea at Ewing


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## Suburban Jungle Life

If my calculations are right, you would need 31 gal of DEF to equal a 50 lbs bag of urea. Can you get 30 gal for $20?


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## Suburban Jungle Life

@JERSEY Walmart supertech DEF is $7.88 for 2.5 gal which is $94.56 for 30 gal. That's a lot more than $20 for a bag of urea. Did you find it cheaper? The OP got it for free so it makes sense for him.


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## Greendoc

DEF seems to be the handiest supply of soluble N for people that do not have access to a farm or golf supply warehouse


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## JERSEY

Ok, I guess UREA granular bags is the cheaper way.

Thank You


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## lawndog

Used Def for the fist time tonight. Too expensive for the size of my lawn 8K sq. ft. I used the .25 lb per K and could only get one use and a half out of the 2.5 jug. Seems cheaper to go the 46-0-0 route and dissolve it yourself.


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## Lust4Lawn

Yes, it is cheaper to buy granular and dissolve. I primarily use AMS for my nitrogen needs but instead of having a big bag of urea laying around, I find it far more convenient when I want to use urea to just use DEF.

10 oz of DEF = 0.1 lbs of N


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