Specialists can be promoted to corporal, the lowest rank of non-commissioned officer, or NCO. An NCO is an enlisted man with the responsibility to lead other soldiers. Corporals lead teams of a few soldiers within a squad. Each squad of as many as 10 soldiers is led by one or more sergeants or a staff sergeant. In squads with a staff sergeant, the staff sergeant commands any other sergeants in the squad.
Organic soil is soil that contains more than 30 percent of decayed organic material from dead leaves, stems and animals, and this material gives the soil a rich color and fibrous texture. Organic soil also receives and retains moisture, which makes it highly supportive for plant growth.
Sandy soils are the result of the weathering and disintegration of a variety of rocks such as granite, limestone and quartz. This type of soil is easy to cultivate but, since it allows for more drainage than needed, it is important to water it regularly, especially during summer days. As sandy soils don't allow the water to pool around the roots, they are a good choice for plants that have a tendency to suffer from root decay.