The prevailing theory at the time was that plants grew by eating soil, and van Helmont devised a clever investigation to test this idea. He weighed a willow tree and weighed dry soil. He planted ...

Students could replicate the experiment using cress, but instead of focusing on the soil uptake, give the plants different quantities of fertiliser in their soil to test its effect on growth.

Plant growth and development largely depend on the combination and concentration of mineral nutrients available in the soil. Plants often ... Trends in Plant Science 10, 22-29 (2005).

Afterwards, discuss with your class that earthworms eat organic matter (the dead parts of plants and animals) such as leaves and food waste. This provides nutrients in the soil that plants can use to ...

SOC input rates are primarily determined by the root biomass of a plant, but also include litter deposited from plant shoots. Soil C results both directly from growth and death of plant roots ...