Sources of Agricultural Limestone
When comparing limestone from different suppliers, be sure to ask for the following information:
1. Type of limestone: Is it either calcitic or dolomitic? Calcitic limestone consists mostly of calcium carbonate. Dolomitic limestone is a mixture of both calcium and magnesium carbonates. Dolomitic limestone should be used on soils with a magnesium soil test of 100 ppm or less. It is an excellent and inexpensive source of magnesium for acidic soils. On soils with a magnesium test greater than 100 ppm calcitic or dolomitic limestone may be used.
2. Guaranteed Minimum Specifications: This will provide the per cent calcium, percent magnesium, neutralizing value, fineness rating and Agriculture Index.
3. Neutralizing value (NV): NV compares the ability of the limestone to neutralize acidity relative to pure calcium carbonate. It is expressed as a percent of calcium carbonate's ability to neutralize acidity. Relative to calcium carbonate, a value less than 100 is less effective, while greater than 100 are more effective. The NV generally increases as the calcium and magnesium content increases.
4. Fineness rating: To be effective limestone must dissolve. A limestone's fineness rating is a measure of its particle size distribution and is determined using sieves. Any material passing through a #60 sieve is consisted to be fully effective. Material that passes through a #10 sieve but not #60 is considered only 40% effective. Materials that do not pass through #10 sieve are considered ineffective.
5. Agricultural Index (AI): AI is an indicator of a limestone's ability to neutralize acidity. It is calculated using the neutralizing value and fineness rating. It can be used to compare the ability of different limestones to neutralize soil acidity. The higher the AI the more effective the limestone on an equal weight basis. The average AI of limestone sold in Ontario has been about 75.
For more information about limestone, managing soil pH with lime, neutralizing value, fineness rating, calculating the Agriculture Index and determining the amount of lime to apply can be found in OMAFRA Publication 811 Agronomy Guide for Field Crops, Chapter 9.
Suppliers of Agricultural Limestone
This supplier list does not imply any endorsement or recommendation by the Ontario Ministry of Agriculture, Food and Rural Affairs.
For specific questions regarding the limestone analysis or specifications, please contact the appropriate company for their latest analysis information.
- CBM Aggregates
- Coloured Aggregates Inc.
- Dufferin Aggregates
- E.C. King Contracting
- Graymont (QC) Inc.
- Miller Minerals
- Nelson Aggregate
- Omya Canada Inc.
- R.W. Tomlinson Ltd
- Setteringtons Fertilizer
- Sudbury Lime Limited
- Walker Brothers Quarries
Coloured Aggregates Inc.
E.C. King Contracting
Graymont (QC) Inc.
Omya Canada Inc.
R.W. Tomlinson Ltd
Sudbury Lime Limited
Walker Brothers Quarries
Niagara Falls Quarry - 2800 Thorold Townline Rd,
Niagara Falls, ON L2E 6S4
Vineland Quarry - 3614 Fly Rd,
Vineland, ON L0R 2C0
Phone number for both Niagara sites: 905-680-3755
Email for both Niagara sites: email@example.com
Walker Aggregates - McGregor Quarry
6781 North Side Road,
Amherstburg, ON N9V 2Y9
Walker Aggregates - Severn Pines Quarry
2646 Nichols Line,
Orillia, ON L3V 6H3
Walker Aggregates - Keppel Quarry
178763 Grey Rd 17,
Owen Sound, ON N4K 5N4
For more information:
Toll Free: 1-877-424-1300