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Discussion Starter · #1 ·
Hey All,

Got a requirement for calcium and sulfur for a field. What is a "typical" analysis of gypsum for figuring? I need 189 lb/A Ca, 28 for S. Also need some Mg, any sources for that if I try to do it?
 

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Discussion Starter · #5 ·
OK, I'm confused. Well, ignorant of how this works is really a more accurate statement.

I'm also putting lime, dolomitic lime, on the field. Which is CaMg(CO3)2.
Gypsum is CaSO4 - 2H20

So, is the Mg in the lime a source for Mg then, or is it tied up? How about the Ca, same question? If I figure Gypsum for total Ca, I get a crap ton of S. If I get some Ca out of the lime, and put on less Gypsum, it would be more optimal perhaps? The lime recommmendation is for pH only, I don't know how it works in supplying these nutrients.

I've never used this lab before / paid for this detailed of an analysis. I'm used to seeing recommended lime / A for pH, and N-P-K for deficit and crop removal.
 

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Don't use dolomite lime it's basically snake oil. Get lime sand if available with the highest neutralising value possible. What's are your ph levels & what increase are you aiming ?
Nothing wrong with the extra sulfur it's basically free., can allow you to use a cheaper source of granular fertiliser with out the S in it.
 

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Discussion Starter · #7 ·
Don't use dolomite lime it's basically snake oil. Get lime sand if available with the highest neutralising value possible. What's are your ph levels & what increase are you aiming ?
Nothing wrong with the extra sulfur it's basically free., can allow you to use a cheaper source of granular fertiliser with out the S in it.
Hmmph. All 3 labs in the state I've used recommend dolomite. And my pH's go or maintain where they need to.(?) So your opinion is interesting to me!:confused: It does take a few months to work, perhaps that's the difference your point is about. Kinda moot, 3 places around here I would buy inputs from all just sell dolomite. And I can get beet lime too, but that's another fiasco, just search my threads! LOL:D:mad:

But I do have to worry about the extra sulfur! The S in Gypsum is in SO4, which with water form sulfuric acid. That means it fights the lime in the pH battle!

Learned a lot yesterday. . . .and a conversation with seed man/consultant last night. Not going to put on Gypsum because of the pH requirement more important that the S at this point. Will put on some AMS next year at some point for S.
 

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Bent is that taking into account neutralising value? Higher neutralising value = less tonnes per acre= less cartage cost. And you can spread more area in a load. Better lime might be cheaper even if it is further away with in reason.

Google Aglime Australia there is lime calculator which will take the guess work out where to get it from. You just need to analysis results of each source of lime & know how much a tonne it will cost you.
 
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