Download Introduction: It is already known that grass seems to be inhibited

Introduction:
It is already known that grass seems to be inhibited around areas where one spreads salt in the
winter. While it is possible that the grass in being limited by the temperature of the
environment at the time, it may also be due to activity of sodium chloride (salt) on the grass
itself.
Hypothesis:
Grass growth is inhibited by a high salt concentration in the soil.
Prediction:
If there is high salt concentrated in the soil, then the grass will not grow well.
Controlled experiment:
First, mark out a spot of land that has the dimensions 1 foot x 1 foot. Identify this area
by cordoning off the land with a rope around the perimeter of the space. Repeat this process by
roping off a second area of the same dimensions a small way away from the first area. Put a
marker in the first area that says “Control” and a marker in the second area that says
“Experiment.” For this experiment, assume that all other soil minerals are identical.
Take salt measurements of both areas and record the findings in a scientific notebook.
Add a controlled amount of salt to the area that has been market with “Experiment” as
mentioned above. Identify the amount of salt used as Day 1 of the experiment. Take readings of
the growth of the grass at the same time every day for 10 days. Record this information in your
laboratory notebook. On Day 10, compare the heights of the grass in both squares listed above.
Record this data in your notebook. Compare the final height of the grass in the control area
with the height of the grass in the experimental group.
Results:
Grass from the control area grew to a final height of 2 inches. The grass in the
experiment area grew to a final height of only 1 inch. As we may assume that all the
experimental conditions were identical, we can confidently assert that it was, in fact, the salt
that negatively affected the grass growth. This information will tell us to be extra careful when
applying salt in the area of a driveway or sidewalk in the winter so as not to harm the
surrounding grass. Furthermore, we can also state that the temperature of the two areas of
grass was the same throughout the experiment, so it was not the temperature of the
environment that affected the grass growth.
Sodium in extremely small amounts is needed for healthy plant growth. Under normal
conditions, it is available in acceptable quantities in the soil already. However, if grass is
exposed to too high a concentration of salt, this will probably kill the vegetation because the
cells of grass contain a certain amount of water and other dissolved molecules. When
surrounded by water that contains a larger amount of salt there is a general rule that water will
try to move between the inside and the outside of the cell wall to make the amount of
dissolved molecules equal. So a high concentration of salt outside the cell wall will suck the
water out of the cell and eventually cause the cell to shrink or collapse (Michael, 201
References
Michael (2010) How Does Salt Affect Lawn Grass & Prairie Grass Growth?
http://homeimprovementquestion.com/how-does-salt-affect-lawn-grass-prairie-grass-growth/
last accessed July 19, 2011.