Lime ECCE & What Your Lime Really Does

ECCE is a lime's real neutralizing power once you account for both its chemical purity and how finely it is ground. The formula is ECCE % = CCE × fineness efficiency, where CCE (calcium carbonate equivalent) is purity vs pure CaCO₃ and fineness efficiency is the mass-weighted share of particles fine enough to react. A lime can have 95% CCE but only 60% ECCE if a third of it is too coarse to dissolve.

Divide your target pure-CaCO₃ rate by the lime's ECCE expressed as a decimal: adjusted rate = target rate ÷ (ECCE ÷ 100). For example, a 4 t/ha pure-lime target met with a 62% ECCE source needs 4 ÷ 0.62 = 6.45 t/ha. The lower the ECCE, the more tonnes you must spread to get the same pH change.

Lime neutralizes acidity only at the surface of each particle, so finely ground lime dissolves and reacts far faster and more completely. By a standard convention, material coarser than 8 mesh barely reacts (≈ 0% efficiency), 8–20 mesh is partial (≈ 20%), 20–60 mesh is about 50%, and material finer than 60 mesh reacts essentially 100%. Coarse lime is mostly inert filler you are paying to haul.

Higher is better. An excellent lime has a fineness efficiency above 85% and an ECCE close to its CCE; a poor lime wastes a large share to coarse particles. Many states sell lime on a guaranteed minimum ECCE (sometimes called ENP or ENV) precisely so buyers compare neutralizing power rather than just price per tonne.

No — compare cost per ECCE-tonne. A cheap, coarse 50% ECCE lime can cost more per unit of actual neutralizing power than a finer, pricier product, because you must spread and haul twice as much. Divide the delivered price per tonne by the ECCE fraction to get the true cost of neutralizing acidity.

The fine fraction reacts within the first season, so a finely ground lime can shift pH measurably within 6–12 months, while coarse particles keep reacting for two to three years. The calculator's timeline puts the fast (fine) pool in year 1 and finishes the slow remainder over roughly three years, steepening as the lime gets finer.

CCE (calcium carbonate equivalent) is purely a chemistry number — the neutralizing value of the material vs pure CaCO₃, ignoring particle size. ECCE multiplies CCE by the fineness efficiency to capture how much of that chemistry will actually react in a reasonable time. ECCE is always less than or equal to CCE.

Often, slightly. Pure dolomite (CaMg(CO₃)₂) has a CCE around 108 because magnesium carbonate neutralizes more acid per unit weight than calcium carbonate, so field dolomitic lime is typically 95–108% CCE versus 85–100% for calcitic. Dolomite is harder, though, so it tends to react a little slower at the same grind.

They have very high CCE (≈ 120–135% for hydrated lime, ≈ 150–179% for burned/quicklime) and react within weeks because they are fine and chemically active, so you spread far fewer tonnes. They are caustic and harder to handle, so they suit fast pH correction or small areas more than routine field liming.

Enter the mass fraction of your lime in each US-standard sieve class: coarser than 8 mesh, 8–20 mesh, 20–60 mesh, and finer than 60 mesh. These come from the sieve analysis on a lime-quality or spec sheet. The fractions are auto-normalised to one, and each class is weighted by its reaction-efficiency factor.

Yes. Pelletized lime is finely ground limestone bound into pellets that break down to powder in moist soil, so it behaves like a very fine lime once wet — high fineness efficiency and a fast year-1 reaction. Select the pelletized preset or enter its sieve analysis; its ECCE is usually close to its CCE.

Take your lime-requirement target on a pure-CaCO₃ basis and divide by 0.70. A 3 t/ha target becomes 3 ÷ 0.70 = 4.3 t/ha of the 70%-ECCE product. Always size the spreader on the ECCE-adjusted rate, not the pure-lime number, or you will under-lime and under-correct the pH.