Marah fabaceus, commonly referred to as the California Manroot, Old man root, or the Wild cucumber, is an almost shockingly vigorous vine native to the San Francisco Bay area. There are in fact five manroots native to California, with Marah fabaceus being the locally prominent species. Since moving in to our lovely home, each spring incites the battle of the manroot vine, as our neighbor’s lushly growing vine makes every attempt to find its way into our serene little oasis. The rampant growth is triggered by the winter and spring rain, and as soon as we enter our prolonged dry season the foliage backs off, the life of the plant retreating to an oasis under the soil- its oft proclaimed giant root that can be (seriously) the size of a human.
I must admit I haven’t actually seen the root, just the above-ground plant and that combined with the legend of the root is enough to make me nervous. Our neighbor’s yard is succumbing to this vigorous plant:
As it reaches over and through the fence, I must act quickly lest the fruit mature and eject (yes, eject!) seed into our yard. I’m a tad surprised this thing hasn’t consumed San Francisco. Apparently summer watering regimes can keep the plant in an active growing state as mentioned by local expert Jake Sigg in his description of this plant on California’s Native Plant Society’s (CNPS) website:
As a volunteer at the San Francisco Botanic Garden, I recently spent an afternoon scrambling through trees and shrubs trying to remove the vine from the Australian section of the garden. I had hopes of finding the source of the plant’s innumerable stems and perhaps even digging to reveal this legendary root. It was not to be revealed that day though, leaving that discovery for anther day.
Some of you may recognize the name Marah, as it is taken from the Bible,
“So Moses brought Israel from the Red Sea…and when they came to Marah, they could not drink the waters of Marah, for they were bitter; and therefore the name of it was called Marah.”-Exodus 15:22
As the name and reference suggest, the plant is extremely bitter. Mr. Sigg in his CNPS entry notes that if you “touch your tongue to a cut root…your jaw will lock.” Though commonly referred to as the Wild cucumber no parts of this plant are edible, but does have some medicinal use mostly as a purgative, though some Native American tribes used it to sooth aches and pains (http://en.wikipedia.org/wiki/Marah_(plant)). They also used a mash of the root to stun fish for ease of fishing.
An interesting plant indeed (and native to boot) though I’m thankful its not in my backyard.