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Figure #4 displays the comparison between the average weights per treatment of the mustard plants in intraspecific competition and interspecific competition. It also compares the weights per treatment of the wheat plants in intraspecific competition and interspecific competition. In the interspecific competition, the number of plants ( of the particular species being documented) does have an additional number of the other species in its pot which is indicated in the figure. Both the mustard and the wheat plants had, overall, higher average weights per plant as the number of plants per pot decreased.

Discussion:

The intraspecific data in figure #3 of a line graph was designed to visualize the density data for the mustard plant average weights compared to that of the wheat, per treatment. We can clearly see that the mustard plants had greater average weights at every treatment. This may be due to faster growth by the mustard plants or the fact that that they have more above-ground biomass than the wheat. Since we haven’t taken into consideration the below ground biomass, we will ignore the latter, for now.

Also, as our hypothesis projected, the average weights of the plants per treatment decrease as the density, or number of plants per pot, increases. This is due to the competition of the plants for nutrients in an environment in which the nutrient levels and life necessities are fixed. As the number of plants increases, the amount of nutrients per plant decreases and thus, each plant has less nutrients than the pot treatment before it with less plants.

The interspecific data for low density data in figure #1 showed us that predation was occurring. The Mustard exhibited a higher than optimum overall percent yield and the wheat, overall seemed to be below normal. Although the wheat did have one percent yield plot point that was higher than its optimum, the trend for the line graph was below the optimum. This information lead us to believe that the mustard was the "predator" because it seemed to take away nutrients from the growth of the wheat, which is the reason the percent yield of the wheat was lower than optimum.

The reason the mustard species dominated over the wheat could be for two reasons: 1) The mustard is a faster growing species and its plants mature early and are able to dominate in that fashion over the immature wheat. This conclusion was reached after examining the intraspecific data, where the mustard had higher averages of plant weight per treatment; or 2) The mustard is simply a more aggressive species that has adaptive features which enable it to overtake plants such as the wheat.

For figure #2, The Dewitt Diagram of high density data, there did not seem to be predation as in the low density interspecific treatments because there was not as great of a distinction between one species benefiting and the other costing. Overall, both species seemed to benefit and have higher percent yields than their optimum. This is considered mutualism because they both benefited. However, the mustard did still have a distinctively higher percent yield. Concerning the very high data point at 131%, there could have been a data collection error or a calculation error involved. This is not to be considered valid because it is impossible to have over 100% yield. However, it is taken into consideration as a high value (over its optimum percent yield) because the data trend is such.

As for the Total Pot Productivity Curve, it simply represents the biomass of the two species combined and therefore allows us to see the overall productivity compared to the optimum. In the case of the low density data in figure #1, the Total Pot Productivity was higher than optimum in some points and lower in others, reflecting the higher % yield of the mustard and the predation of the mustard upon the wheat. In the high density data in figure #2, the Total Pot Productivity Curve was entirely above the optimum level. This is because of the combination of wheat not overall below its optimum percent yield and the mustard having some very high percent yield figures.

Refering to our hypothesis, the average weights of the mustard plants interspecific experiments were higher than those in the intraspecific experiments, per treatment ( plant #). This is observed in figure #4 . These results are because in the interspecific experiments the plants did not have to compete with their own species that needed similar nutrients at the same growth stages. Also, as we predicted, the plants produced less as the density grew. This was observed in the intraspecific data when the average weight of the plants per treatment decreased as the number of plants per treatment increased. And in the interspecific data, in both high and low density, the percent yield of the plants went down as there were more plants added, in each treatment. This was exhibited in both the mustard and the wheat plants for all experiments.

One aspect which we paid respect to in our consideration of our experiment was that in our data we only measured the above-ground biomass and not the plant structure below ground. This could be a factor that could introduce error in our results. This is because a plant species such as wheat or mustard could have an extensive root structure which could add a significant increase to its measurement of weight. Some plants, as we know, produce most of their biomass underground, such as a potato or carrot.

Our data proposed a question as to what might happen if this experiment was extended over a longer period of time, or each pot was replanted to sow new generations. We concluded that, first of all, there would be much

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