Glad to oblige. I too have about 4.0 acres in food plots and use CREDIT EXTRA, which is a non-Monsanto Chemical Corp. generic 41% glyphosate herbicide/surfactant mixture. That's a mouthfull.
Monsanto patented "Roundup", which is 41% glyphosate herbicide/adjuvant/surfactant mix.
http://en.wikipedia.org/wiki/Roundup .
Adjuvants allow chemicals to work together better without providing any real effect by themselves.
http://en.wikipedia.org/wiki/Adjuvant .
Surfactants allow chemicals to break the water surface barrier on the leaves of plants, especially waxy leaves, and allow the even distribution of chemicals over the entire plant absorption area.
http://en.wikipedia.org/wiki/Surfactant .
That said, shoot me a PM and I will shoot you a simple Excel Spreadsheet for the calculation of any lesser percentage of glyphosate concentration in any quantity of water from any known higher glyphosate concentration.
You input the variables:
Size of your GLY product container [typically 1.0 or 2.5 gallons; could be 55 gallon drum]
Starting concentration of GLY [typically 41%]
Desired Concentration [typically 0.50% to 2.0%. Most express excellent plant kill at 0.50%]
Size of your Sprayer [1.0 gallon, 2.0 gallons, 25 gallons, to any reasonable capacity (infinity!)]
Calculates:
Number of ounces of concentrate to make one (1) 25 gallon mixture.
Number of ounces of concentrate to make your sprayer capacity mixture.
I add that this is predicated on hand spraying and not boom spraying, which application is different - but concentrations are the SAME.