PRACTICAL ACTIVITY
COMMUNE DI SCANDIANO
2. DETERMINATION OF SOIL TEXTURE Aim of the ac vity: This ac vity method permits to easily define the rela ve quan es of sand, silt and clay and observe in an empirical way a very important soil quality, texture, a key concept in order to determine soil fer lity. ź Target group: students, adults, seniors ź No. of par cipants: max. 12 ź Where: everywhere (classroom, terrain) ź When: all year round if not the ground frozen ź Dura on: 1 hour ź Equipment and other material: glass jars, water, soil Content An average soil sample is made of 45% minerals, 25% water, 25% air, and 4% organic ma er. Mineral par cles of
ITALY
different sizes, such as sand, silt and clay, give soil an essen al feature called texture. Different percentages of sand, silt and clay determine the quality of the soil with respect to its porosity, malleability and fer lity. For example, a clay soil (with a high percentage of clay in its texture) will be hard to work with, since it is heavy and soaked. Sandy soil is porous and easily malleable, though neither water nor nutrients are going to remain in its structure. The best soil texture for farming use is the sandy–loamy one, where the presence of silt is balanced by a small percentage of sand and clay. There are several methods in order to determine different quan es of clay, silt and sand. One of them is empirical and approximate, though s ll effec ve for those who don't need a precise measurement.