Fallow and topsoil storage

Stored topsoil on building site.

Topsoil is often scraped off and stored in heaps. Soil can be stored for months on building sites and then subsequently spread out again once building is finished. Soil is stored for longer periods (e.g. years) during surface mining and the soil re-spread and rehabilitated with plants once mining operations have finished. However, during storage, mycorrhizal fungal spores germinate and die in this stored soil as there are few plants for them to grow into and thay are dependent on plants for survival. Vegetation planted into this topsoil once it has been spread, often fail to thrive. One explanation is that the soil is depleted of the spores of the mycorrhizal fungi which help in plant nutrition.

A similar thing happens during long fallow where the soil surface is bare of plants for many months.