Option A Observation: During the winter, you spread salt daily on your driveway to melt the snow. In the springtime, when the lawn begins to grow, you notice that there is no grass growing for about 3 inches from the driveway. Furthermore, the grass seems to be growing more slowly up to about 1 foot from the driveway. Question: Might grass growth be inhibited by salt?
Introduction
Plants show normal growth when suitable growth factors and soil conditions are available (Kadlec & Knight, 1996, p. 691). Grass, being a plant, is expected to grow well when suitable conditions are present. Grass grows uniformly when subjected to these suitable conditions. During winter, as snow covers almost everything, salt is usually poured on it so that it can melt. This is because salt acts as an impurity, thus lowering the melting point of the snow. However, during the spring season, part of the grass that was covered by snow and salt poured on showed no growth. The ones that managed to grow had a poor growth. It is expected that since all the grass is being exposed to the same conditions in spring time, they should grow well and uniformly.
Hypothesis
If during springtime the grass from the driveway where salt was poured showed slow or no growth while other grass of the lawn grew well, then the salt had altered the normal growth of the grass. The normal growth of driveway was hindered by the salt presence in the soil.
Controlled experiment method
Four pots of the same size each with a grass planted were placed outside near the garden and allowed to grow normally. After one week, 20 ml of distilled water was poured into the first two pots (pot A and pot B) while 20ml of salt water was poured into the other two pots (pot C and pot D). This was done repeatedly for another one week at a frequency of twice a day. The pouring of water to these pots was done simultaneously and all pots were subjected to the same environmental conditions. Pots A and B were the controls. The growth of all the grass was checked thereafter and observations recorded.
Results
The grass in pot A and pot B grew well and looked very healthy. The grass in pot C grew weakly and had a lighter green color. The grass in pot D withered.
Conclusions
According to the observed results, the hypothesis can be accepted. The growth of the driveway grass was indeed affected by the poured salt. Water is essential for grass growth. The roots of grass absorb water from the soil to be utilized by the grass for normal growth. This is achieved by osmosis (Thoday, 2015, p. 86). Pot A and Pot B were able to absorb water by their root hairs making then grow normally and healthily. However, for pot C and pot D where salty water was used, root hairs were unable to absorb water from the soil. This is because soil water was hypertonic to root hair cells. This lead to poor growth for the grass in both pots.
This means that when salt was being poured to the snow, the snow melted and dissolved the salt. The solution then dissolved in the soil, thus creating a salty soil. The grass on from the driveway was unable to absorb water due to this. Since water is essential to their growth, lack of it led to their slow growth or no growth at all.
Some plants will grow normally under the salty conditions as they have adaptations to such environments. However, grass cannot tolerate saline soil conditions.
References
Kadlec, R. H., & Knight, R. L. (1996). Treatment wetlands. Boca Raton: Lewis Publishers.
Thoday, D. (2015). Botany. Cambridge: Cambridge Univ Press.
