Rot Race Lab Report


To see how fast organisms and materials decay under certain conditions.

Procedure: We gathered 4 2-liter plastic pop bottles and cut them to assemble
the drawing below. Near the bottom we placed a siv to let juices drain through
into the bottom 2-liter. Then we stacked materials and organisms on top of each
other until it was about 20 cm tall. We then randomly poked holes into the sides
of the pop bottles to let air escape. This is the order we placed the materials,
from top to bottom; 2 cups of dirt, 13 pieces of melon, I cup of soil, 3 chunks
of wax, 2 cut up bananas, 4 slices of apple, 1 banana peel, many slices of
carrot peelings, 1 cinnamon roll, apple sauce, 1 slice of bread, and then the
siv. Next we let it sit and made observations every Tuesday and Friday. We
checked the color change, smell, height (cm), temperature (degrees Celsius),
mass (lbs), Ph, and we checked for living organisms. Drawing of set-up:

Conclusion: After the experiment we decided that the bread decomposed the best.

I believe this because the bread was the most porous, which allowed more
bacteria could get to it. We also decided that the wax decomposed the worst
because it was the hardest and most compact. We knew that decomposition was
taking place because mold was growing on some of the material and the height and
mass were decreasing. When an organism decays it loses it size and mass just
like our rot column. Improve: One of the ways that we could have improved our
experiment is by placing the material on top of the other material and let it
set, instead of mashing it and mixing it together. Also we could have put in
materials that were harder to decompose. Another thing we could have done was to
put more holes in the bottle. That would have let more air escape therefore it
wouldn't have smelled as bad. Or maybe we should have placed our rot columns out
side!