Tikalon Blog by Dev Gualtieri

Pumpkin Propagation

November 24, 2016

There are quite a few food items associated with the US Thanksgiving holiday, the most common being turkey, cranberry sauce, and pumpkin pie. I've always been partial to the full-berried cranberry sauce, as opposed to the jellied variety. I'm also old enough to remember the "Great Cranberry Scare of '59."

About two weeks before the 1959 Thanksgiving holiday, it was revealed that some of that year's cranberry crop contained trace quantities of the herbicide, aminotriazole. In laboratory testing, aminotriazole had been shown to cause thyroid cancer in rats. While 99% of the cranberry crop was not contaminated, there was no way for the consumer to know whether a particular lot was nontoxic. The product was not recalled; but, as could be expected, it was a generally cranberry-free Thanksgiving that year. My family tried kumquats instead, but they weren't as satisfying.

Pumpkin pie is so favored as to be a rival for apple pie. Read, for example, the following song lyrics from an 1806 book,

America's a dandy place:
The people are all brothers:
And when one's got a punkin pye,
He shares it with the others.[1]

Fig. 1 of US Patent No. 5,811,160, 'Carvable artificial pumpkin,' by Jeffrey A. Chapman.

Pumpkin harvesting extends from Halloween through Thanksgiving.

Fig. 1 of US Patent No. 5,811,160, "Carvable artificial pumpkin," by Jeffrey A. Chapman.

(via Google Patents.)

Presently, there are quite a few "pumpkin-spiced" items, including coffee (which, as a coffee connoisseur, I will definitely not try). The traditional spice mix is mostly cinnamon (55-65%) with about 12% ginger, 12% nutmeg, 6-9% allspice, and 6-9% cloves, although the cloves are sometimes omitted.

The word, pumpkin, comes to us from the Greek, πεπων, "large melon." While the characterization of pumpkin as a melon seems strange, pumpkin is technically a fruit, since it bears seeds. Other vegetables that are technically fruits are tomatoes, peppers, cucumbers, and avocado. They propagate by dispersal of their seeds, often by being ingested by an animal and excreted elsewhere.

The general term, squash (examples shown), describes multiple species in the genus, Cucurbita. Pumpkin is of the Cucurbita pepo species of Cucurbita.

(Pennsylvania State University photo by George Perry.)

An interesting study by a diverse team of scientists from Pennsylvania State University, (University Park, Pennsylvania), the University of Warwick (Coventry, United Kingdom), the University of Cambridge (Cambridge, United Kingdom), the Smithsonian Institution (Washington, DC), and the Santa Fe Institute (Santa Fe, New Mexico) suggests that we wouldn't have our pumpkin pies if it weren't for the existence of large herbivores, such as mastodons, and their later demise.[3-4]

The wild pumpkin varieties of the distant past (more than 10,000 years ago) were bitter and not palatable to humans and small mammals.[3] Large herbivores, however, were willing to eat them, since these large animals had fewer bitter taste receptors than smaller animals.[4] The possible reason for this is that larger animals can't be that particular about what they eat, since it takes a lot of food to maintain a large body mass. The bitter pumpkin seeds were dispersed in the dung of these large-bodied herbivores.[3]

Fossilized Cucurbita seeds found in mastodon dung.

Fossil feces are called coprolite.

(Pennsylvania State University photo by Lee Newsom.)

Fruits of the Cucurbita were initially used by humans for purposes other than food, such as containers and floats for fishing nets.[4] Eventually, some of these cultivated Cucurbita mutated to be less bitter; and, according to Logan Kistler, an author of the study from the University of Warwick, Cucurbita may have been domesticated multiple times in different places.[3-4] Says Kistler,

"There is a huge amount of diversity in some of the domestic species and between them as well... Cucurbita pepo is probably the most variable, with jack-o-lantern pumpkins, acorn squash, zucchinis and others. Cucurbita moschata contains the butternut squashes and the kind of pumpkin that goes into the cans that a lot of folks will be baking into pies in a few weeks."[4]

The ecological shift during the Holocene and the extinction of the megafauna led to extinction of many wild Cucurbita species.[3] The cultivated varieties became the dominant varieties.[3] This research was supported by the Wenner-Gren Foundation, the Natural Environment Research Council, and the Smithsonian Institution.[4]

Pumpkin Propagation

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