Humate

This is dried humic acid, which has become a solidified organic material from drying.

  Humic Acid

The part of humus which is soluble in water. It is typically dark brown to blackish in colour. Humic acid can be extracted, with a solution of sodium hydroxide, from any material containing well-decomposed organic matter, such as compost. This extractant helps to dissolve most of the organic matter. The solution is then acidified to a pH of about 2, which flocculates the organic material from the liquid portion to create humic acid. It is very resistant to any further breakdown. The remainder in solution is fulvic acid.

  Humification

The process of decomposition of organic matter to form humus.

  Humification Coefficient

The ratio of carbon from returned clippings and organic matter which remains in a soil profile at the end of a year. High rates of decomposition result in a low ratio of humification coefficient, which is typically around 0.25 for grass leaves. This can still add up to a significant build-up of organic matter within a turf surface, hence the need for appropriate maintenance practices to reduce any residual build-up.

  Humin

The part of humus which is not soluble in water. It is typically black in colour.

  Humus

Decomposed organic matter which contributes to increased soil nutrient availability and retention in a soil, as well as improved soil structure. It consists of Fulvic acids, Humic acids, and Humin. Humus is also termed Humified Organic Matter. It can also be categorised as Mor, Moder, or Mull.

  Hybrid

A plant resulting from cross-pollination and breeding of two different species or cultivars, with the resultant plant being called an F1 hybrid and these are often sterile plants. The aim is to improve one or more features within a plant. For example, to improve disease resistance, or to improve wear tolerance.

  Hydrated Lime

This form of lime is Calcium Hydroxide and is made by treating burnt lime with water. It is used in reducing acidity on agricultural soils but would burn grassed areas if applied to such areas. It is also known as slaked lime.

  Hydration

The adsorption of water molecules to a mineral, causing it to swell and weaken

  Hydromulch

The application of a liquefied mulch onto a soil area. It may also be applied on newly plated areas as well. This technique can be useful on relatively steep slopes and areas which are prone to erosion.