Calcitic lime vs. dolomitic

[Bowsnbucks]

For you ag-experienced guys ....... what's the difference between them - and what soil conditions warrant the use of each one??

When someone uses the term "ag lime" - does that term apply to both kinds of lime - or just one??

 

[Wind Gypsy]

For you ag-experienced guys ....... what's the difference between them - and what soil conditions warrant the use of each one??

When someone uses the term "ag lime" - does that term apply to both kinds of lime - or just one??

Bows, you probably saw my recent thread related to this topic?

I've seen them both referred to as Ag lime in fact i mistakenly bought dolomitic lime called ag lime from a vendor who also has a "hi-cal" lime that is calcitic ag lime. I think i've got a basic understanding of benefits of each but I'll let the "ag-experienced guys" with more knowledge weigh in on that.

 

[FarmerDan]

The powdered stuff we apply to fields to increase soil pH is a mined mineral hammered and ground to a specified particle size. Some of the native limestone mined for ag use is nearly all calcium. This is called calcitic lime. It probably has some magnesium but it's inclusion is inconsequential. Where the mined limestone is high in magnesium AND calcium the ag lime is called dolomitic. I think Wind Gypsy's dolomitic lime analysis was 18% Ca and 11% Mg. Calcitic lime is more like 40% Ca with negligible amounts of magnesium.

Conventional thinking says to always use calcitic lime UNLESS you have a soil test where magnesium levels in the soil are low or the ratio between Ca & Mg are out of balance. If you soil is low in pH and in need of magnesium use dolomite.

There's much debate about Ca:Mg ratios and such discussion is probably best left to the soil scientists and agronomists.

I guess the term "ag lime" might mean different things to different people. Where I come from and in my work ag lime is prepared (hammered and ground) so the particle sizes have some soil neutralizing capability - The percent of the material passing thru different screen mesh sizes is one measure for ag lime. Typically it all passes thru a 60-mesh screen with an upper limit of some percent passing thru a 100 (sometimes 200) mesh screen. The source of the material is irrelevant to the definition of "ag lime."

There are other lime products much more granular with little neutralizing capability because of its large particle size. Again, where I come from and based on some of my early work (I milked cows for a while but figured out what was causing it and got it stopped), barn lime is such a product. It's spread on wet concrete floors to keep cattle from slipping to their eventual and untimely deaths.

 

[SD51555]

The quick and dirty is this:

Calcitic lime is just that, a calcium-only or calcium-majority lime.
Dolomitic is one that has a good amount of magnesium in it. It can vary, but 1 part magnesium to 2 parts calcium or less is common.

I once sampled Waukesha lime and it was 11% magnesium, and 22% calcium. I got some pell at Menards that was 3% magnesium, 33% calcium. I just picked up some calcitic at Fleet Farm over the weekend that was 1% magnesium, 38% calcium. So you've gotta flip your bag over to know what you're getting.

Calcitic is good on heavy clay soils
Dolomitic is good on sandy soils

In my mind, ag lime is anything that isn't pell lime. There are fineness grades that affect how fast it gets to work, but I never get too bent out of shape about that. I'm gonna use the larger particles in the years to come.

 

[Bowsnbucks]

Calcitic is good on heavy clay soils

We have clayish-loam soil at camp. The deeper we dig, the harder the clay. I'll have to see what our newest soil tests show for magnesium.

 

[TreeDaddy]

What are y'all seeing for lime prices this year?

I was quoted 55$/ton yesterday in east texas

bill

 

[Wind Gypsy]

Edit: did some math.. They told me it was something like $38/ton but total price was like $750 for 16 tons so it must have been more than that or they tacked on an additional charge for only getting a small load.

 

[Maddog66]

$933 for 23.5 ton = $39.70/ Ton. 150 mile round trip.

If you had a dump truck and a CDL it would be $11.50/ton at the crusher, I was told.

 

[Nightvision]

I paid $35.00 a ton earlier this year but I had them dump it on the trailer. I’m in middle Georgia.