Earlier this week I wrote about an entirely different sort of swamp. This brief post is about a topic much more in tune with the holiday season: cranberries. Grown in bogs with layers of peat, sand, gravel, and clay, cranberries are native to North American wetlands (our readers across the pond will probably know the European variety of the fruit as lingonberries). In the United States they are primarily grown in Massachusetts, New Jersey, Oregon, Washington, and Wisconsin (ordered alphabetically, not by output). Something not many people may know is that these cranberry bogs are cyclically flooded with vast amounts of water every season; some might worry over the constant waste of this precious liquid in areas of major cranberry production, or the contamination of water tables with pesticides and fertilizers common to agricultural use.
But I am about to tell you about some of the advantages cranberry-growers have over other industrial agriculturalists in terms of their water utilization. Why will I share this with you? Well, cranberry sauce features prevalently in the traditions of recent holidays, namely Thanksgiving and Christmas (and was thus probably consumed in an overwhelming majority of American households at least once in the past 60 days), plus my grandparents swear by cranberry juice, but I also recently found out that cranberries–and the water they are flooded with for harvesting–make for excellent art, or sport. What I never would have guessed is that Red Bull would be the one to show me this; just watch the video below:
Now for some more serious stuff.
Several aspects of the cranberry’s ecosystem and environmental needs help the cranberry industry keep its impact on the water table relatively low compared to other agricultural industries. I’ve written about the devastating effects over-use of fertilizers has on ecologies like the Gulf of Mexico, but fortunately, cranberries seem to be less at risk of over-fertilization than other crops. First, fertilizers in aquatic environments have fairly fast and significant effects on numbers of organisms such as algae, which are harmful to cranberries; second, contamination of water sources by excess nutrients will later contaminate organisms that live in that water, including the cranberries; and third, cranberries are thought to prefer ammonium or organic forms of Nitrogen rather than nitrate forms, which along with phosphates are responsible for hypoxia in oceans via runoff (as I wrote here). These three factors serve as incentives for cranberry growers to limit or carefully regulate their use of fertilizers. Plus, since cranberries grow in a bog, or swamp, the ecosystem itself can serve as a filter to purify water, and cranberry growers save money by reusing their old water, as the Wisconsin farmer in the video told us.
In terms of herbicides and pesticides, the use of Integrated Pest Management (a topic for another post entirely), where growers try to remove pests before they affect their crop, helps reduce (but not altogether end) the use of harmful chemicals. Flooding, draining, and sanding (adding sand, which is good for cranberry vines but not for weeds or incubating insects) the bogs have proved effective mechanisms for disrupting pests’ natural cycles of growth. Other techniques such as the biological controls that certain nematodes, bacteria, or synthetic pheromones provide help kill or deter insect pests.
I don’t really have much to say in terms of concluding remarks reflecting on what you should think of the next time you open a can of cranberry sauce, sprinkle dried cranberries over your salad, or drink some cranberry-apple juice (these last two are referred to under trademark as ‘craisins’ and ‘cranapple’ juice by the Ocean Spray cooperative, which by the way was not my main source of information for this post). If you are interested in learning more about the fruit, a great and brief history of cranberries can be found at the Cape Cod Cranberry Growers Association website.