The peanut (Arachis hypogea L.) is a staple of the modern diet. From butter to brittle, it’s ubiquitous. While you may know that peanut is a legume, rather than a nut per se, it may surprise you to learn that peanut has only been a major crop for less than a century. Peanut was mainly a garden or feedstock crop until it became heavily planted in the southern US following the cotton blight in the early 20th century and was popularized in part by the efforts of agronomist George Washington Carver. Another under-appreciated aspect of the peanut plant is how the process of making peanuts starts when a flower is fertilized above ground and ends when the pod finishes developing below ground. In this process, known as geocarpy, fertilization triggers the plant to extend an organ called the peg, or gynophore, straight down. Once the tip containing the fertilized ovules mechanically senses the soil and is out of direct light, that familiar textured pod and the peanuts inside then develop parallel to the surface. A fascinating feature of the peg is that it has a fully formed vascular system that transports water and nutrients. Indeed, if you cut the aerial parts of the plant away from the roots, the pegs can still sustain the green tissue. Just some food for thought next time someone takes you out to the ballgame!
--Ben Blackman
Check out George Washington Carver’s famous pamphlet with 105 peanut recipes here!