Lake Erie eutrophication, in which additional nitrogen and phosphorus enter the lake, will cause plant life to "run wild and multiply like crazy". Since there are fewer wetlands, which are like "Nature's kidneys" by filtering nutrients, as well as greater "channelization of waterways", nutrients in water can cause algal blooms to sprout as well as "low-oxygen dead zones" in a complex interaction of natural forces. As of the 2010s much of the phosphorus in the lake comes from fertilizer applied to no-till soybean and corn fields but washed into streams by heavy rains. The algal blooms result from growth of Microcystis, a
Plant tolerance to herbivory Using simulated herbivory allows for the control of environmental variables, but replicating natural herbivory is difficult, causing plants to respond differently from imposed and natural herbivory (Tiffin and Inouye 2000). Growing plants in the control environment of the greenhouse may also affect their response as it is still a novel environment to the plants. Even if the plots are grown in natural settings, the methods of excluding or including herbivores, such as using cages or pesticides, may also affect plant tolerance (Tiffin and Inouye 2000). Lastly, models have predicted that manipulated herbivory may actually result in less precise estimates of