Soil Texture Test

The texture of the soil was determined through two separate tests.

Qualitative Test
A small hand full of soil was rolled into a ball. Because the sample was drying out, additional water was added to help create the ball. The sample was squeezed between the thumb and forefinger to feel its texture. There was not a very gritty texture to it, yet it was not sticky. When rolled out, a short ribbon was made that soon broke. Based on this, we concluded that the soil was mainly silt or loam.

Rolling the soil into a bal

Squeezing ribbons of soil

Quantitative Test
65 mL of soil was put into a graduated cylinder. Water was added until the container was 100 mL full. We sealed off the opening of the cylinder with a cupped hand and shook it from side to side until the contents were a uniform mixture. This was placed upright and sat overnight. The next day the different layers of sediment were measured.

Water and soil mixture before shaken

Shaken mixture after one day

The next day, the different layers of soil were present. The very bottom of the cylinder was .5cm sand, the middle 10cm silt, and the top 1.5cm clay. The total soil content was 12cm. Percents of each layer were calculated.

These percents were used in a soil triangle to determine the type of soil our sample was. This sample is most likely silty loam.

From the qualitative test, our predictions of a silty or loam soil agrees with the results from the quantitative test. According to the percolation test, this soil type is consistent.

Compared to other soil samples in the class, one sample contained mostly clay and was classified as clay on the soil triangle. Another group found soil at the same site as we did and had soil similar to ours, except with a higher concentration of silt and was classified as silt. One group who got their soil from the school's yard contained much more clay than any other group. This is most likely because different soil horizons and different factors affected how these soils were developed. Although these samples were derived relatively close together, the samples may have had different parent materials.