# Spraying Fertilizer



## TJH (Mar 23, 2014)

Ok guys', it's been a long, long time since science class. If im spraying liquid nitrogen at 11 LBS per gallon and the sprayer is calibrated with water at 8 lbs per gallon and the sprayer is applying 20 gallons per acre will 20 gallons of nitrogen be applied or less or more? I've tried the specific gravity route and only confused myself more. Any help will be greatly appreciated!!


----------



## Growing pains (Nov 7, 2015)

A gallon is a gallon so if you calibrate by volume it will be the same. If you went by weight you'd be under applying. I've never heard of calibrating a sprayer by weight but someone somewhere may do it that way.


----------



## Hugh (Sep 23, 2013)

OK, you say there is 11 lbs. of N per gallon, and 20 gallons per acre. so: 20 X 11 = 220 lbs. of N per acre. I have a hunch the 11 lbs per gallon of N is not right. Did you mix this yourself or buy it pre-mixed? For example, Wilber Ellis makes a product called N-Demand 30 that is 30% N. It also weights about 11 lbs per gallon. If you were spraying this product, then 220 X 30% = 66 lbs of N per acre. Tell me what product you are using, if you mixed it yourself, etc, and I'll give you an answer, good luck!


----------



## Lewis Ranch (Jul 15, 2013)

32-0-0 weighs 11lbs per gallon roughly. That would give you around 3 1/2 pounds of actual N per gallon.


----------



## TJH (Mar 23, 2014)

It's 32-0-0 already mixed.


----------



## Hugh (Sep 23, 2013)

20 gallons per acre @ 11 pounds per gallon = 220 lbs of material per acre. This material is 32% nitrogen, and fertilizer is always sold by weight not by volume.

.32 x 220 = 70.40 lbs of nitrogen you are applying per acre.

Another way to look at it in the future is to think this way: "this stuff weights 11 lbs per gallon and 32% of that is nitrogen. Therefore, .32 X 11 = 3.52. So then, it follows: *every gallon of this material has 3.52 lbs of nitrogen*. If you sprayed 20 gallons, then 3.52 X 20 = 70.40 lbs.

If your soil test says you need (an example, for future use) 100 lbs of N per acre, then divide 100 by 3.52 lbs of actual N per gallon and you will get the number of how many gallons you will need to spray to meet that need.


----------



## vhaby (Dec 30, 2009)

TJH said:


> Ok guys', it's been a long, long time since science class. If im spraying liquid nitrogen at 11 LBS per gallon and the sprayer is calibrated with water at 8 lbs per gallon and the sprayer is applying 20 gallons per acre will 20 gallons of nitrogen be applied or less or more? I've tried the specific gravity route and only confused myself more. Any help will be greatly appreciated!!


You should re-calibrate your sprayer output before each use, and especially when you are changing the material you are spraying.

Why would you spray liquid nitrogen on what I assume is a hybrid bermudagrass when you could replace the spray nozzles with orifice plates and dribble-apply the liquid nitrogen onto the grass? Dribble bands 20-inches apart will not decrease yields. In fact, by harvest time you will not notice any height differences between directly over the band and between bands. This was researched at Texas A&M- Overton in the mid-80s.


----------



## Lewis Ranch (Jul 15, 2013)

I use the teejet 7 streamers. They work good and have less burn.


----------



## TJH (Mar 23, 2014)

Thanks Hugh.


----------

