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calculation problem

2103 Views 20 Replies 10 Participants Last post by  GLAN
if you need .74 ouce per 1,000 sq and i need to cover 17,000 sq ft. so how many gallon of water is needed.

i think i'm missing something also in my calculation
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.74 x 17,000 = 12580 oz.

12580 oz. / 128 (per gal) = 98.3 gal

Is it .74oz per gallon/1000???? or .74 per 5 gallon/1000??? You are missing the gallon rate.
Originally posted by A1 Grass
.74 x 17,000 = 12580 oz.

12580 oz. / 128 (per gal) = 98.3 gal

This should be .74 X 17......not 17,000. This will only give you amoung of chemical.
0.098 gallons
you take the total ounces, which would be 12.58 and multiply by 0.00781 to get the number of gallons needed
Originally posted by tiedeman
0.098 gallons
Nine one hundreths of a gallon of water??!!:D :D :D :D
sorry, but that is what my pesticide appendix booklet say to do to convert ounces to gallons. Now to convert gallons to ounces you multiply it by 128.
He needs .74 oz of chemical to cover 1000 sq/ft. he wants to know how much water to mix the .74 oz in chemical in. He either needs to know.....1. The amount of water the label states to mix .74oz in to cover 1000, OR 2. The rate of his sprayer, ie. how much water he puts down per 1000.
that rate appears to me that he wants to apply Super Trimec or something similar.

So it is .74 ounces to a gal per 1000sqft.

He wants to apply to 17,000sqft

17 gallons of water.
i'll give lesco a call tomorrow.. i'll update you all with what they say.. so everyone here will know the correct fomula.. i went through calculations a year ago in class but i forgot how to do this..
I'll probably get flamed for this, but...

Posters to this site routinely gripe about unlicensed appliers of chemicals. This post and some of the replies are pretty good evidence that having a license does not guarantee competence. As a homeowner I would like to believe that the licensed LCO that I hire to apply chemicals to my lawn knows how to calculate the dilution.

Just my 0.02.
i know people who have put down fertilizer for true chem chem lawn.. trust me they don't know..
In 17,000 sq ft you have 17 one thousand sq ft sections. Therefore you will need .74 X 17 = 12.58 oz of chemical applied to the 17,000 sq ft area.

You need to calibrate your sprayer. Mark off an area 50X20 (1000 sq ft) , spray the area with water and see how many gallons you use.
The simple way-assuming you are using a backpack sprayer, you calibrated it as above and you use 1.5 gallons of water per 1000 sq ft, then simply add .74 oz of chemical per 1.5 gallons of water. For a 4 gallon sprayer in this scenario the formula would be (4 gal/ 1.5 gal ) X .74 or approximately 2 oz of chemical (1.9733)
Hit the submit key too quick. My above example is 1.9733 oz / 4 gals of water.
Fvstringpicker is very correct. You need to calibrate the sprayer to your own application rate. It doesn't help to know how many ounces of chemical per thousand if you don't know how many gallons per thousand you spray at.

Does it take you 1 gallon to cover 1000 ft², or 2 gallons, or what? And if you use different spray tips, your application rate will change. If you use higher pressure, your application rate will change. If someone else uses your sprayer, you will have to calibrate the sprayer to his rate (maybe he walks faster or slower), or you will have to teach him to spray at exactly your rate.
i know i was missing something in my questions but i couldn't figure what it was.. i was thinking the gallons per m but wasn't sure. thanks
Ummmm...see my first post. You do need to know the gallon rate your sprayer sprays. ;) ;) :rolleyes:
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