9 months ago
Wednesday, April 25, 2007
Imagine walking in the country - taking the overgrown path which leads down the dirt bank into the willows... picking your way among the rushes of the creekbank, and then taking a trail which leads into the shady trees beyond. The damp creek aroma smells sweet. Looking around, you can see emerald vines, crawling and clinging to the tree trunks & bushes, with curly tendrils hanging in ringlets beneath the wide ivy-shaped leaves.
As a child, roaming the creeks and wild areas in the Santa Monica mountains of southern California, I was fortunate enough to have had hours of unsupervised time to explore. When over at G's place today, I was reminded of those glorious times of discovery and delight. I loved the creek, with all of its own array of interesting living things (did you ever hear of a horsehair snake... really a parasite but we didn't know that then when we were bringing them home in pails - that is for another day's sharing and also it is much too ugly to put on my blog) and one thing I always loved was the Manroot vine. I saw it clinging everywhere, and succumbed at one point to the curiousity of breaking one of the prickly fruits open to see what was inside. There really isn't much more to this post, other when walking up the steep hill by my house yesterday (trying to get some much needed exercise) I noticed some of the vine growing in the scrubby live oaks next to the road, immediately nostalgically catapaulting me back in time to my parent's home way back when. I am even privileged enough to have an actual Manroot vine growing in my very own backyard, on the stickery holly tree in the deep shady corner by the dogrun. To my great sadness, my own vine is seasonal, and dies back when the first warm spell causes it die away until next storm season. I wish I could just keep it growing all year round - with vines and hairy prickly balls hanging all over my trees and bushes... but alas no. Oh, and why do you suppose it is named Manroot?
I am very sure that the following is much more information than anyone wants or needs to know about this fine plant, so put your head down on your desk and take a nap if you prefer.
And now for your science lesson for the day:
The California Manroot or Bigroot, Marah fabaceus, is the most common of the manroot species native to California. Its range throughout the state subsumes nearly the entire ranges of all the other California native manroots species and intergrades/hybrids between California manroot and the other species are common
Like other manroots, it has stout, hairy stems with tendrils. Vines appear in late winter in response to increased rainfall, and can climb or scramble to a length of 6m. Its leaves typically have five lobes with individual plants showing wide variation in leaf size and lobe length.
Vines emerge from a large, hard tuberous root which can reach several meters in length and weigh in excess of 100kg. Newly exposed tubers can be seen along roadcuts or eroded slopes and have a scaley, tan-colored surface. Injured or decaying tubers take on a golden or orange color.
The flower can vary in colour from yellowish green to cream to white. Flowers appear soon after the vine emerges. The flowers are monoecious, that is, individual flowers are either male or female, but both sexes can be found on the same plant. Male flowers appear in open clusters while females flowers, distinguished by a swollen base, usually appear individually. The plant is self-fertile, i.e. pollen from the male flowers can fertilize the female flowers on the same plant; pollination is by insects ..
The fruit is spherical, 4-5 cm in diameter, and covered in prickles of variable density, up to 1cm long but without hooks. Unripe fruit are bright green, ripening to yellow. The fruit swells as it ripens until finally rupturing and releasing the large seeds. Fruit begin to form in spring and ripen by early summer.
Seeds & Germination
Seeds of the California manroot are large, hard, and very smooth. Fruit usually hold 4 or more seeds. Seeds sprout in the cool wetness of late winter. Seeds have an intriguing germination process. The initial shoot emerges from the seed and grows downward into the earth. This shoot then splits, one part beginning to swell and form the tuber, while the second part grows back to the surface and becomes the vine
The California Manroot grows most vigorously by streams or in washes but is also successful in dry chaparral, at elevations up to 1600 metres. It ranges through most of California except the far northwest and the Mojave. It will tolerate a variety of soil types and acidities, but it requires seasonally moist soil. Vines can grow in full-sun to partially shaded conditions. In mild areas where year-round moisture is available, vines can be perinneal. In the Mediterranean climate areas of California, manroot emerges soon after winter rains begin, grows until late spring, and dies back completely in the heat and dryness of summer.
All parts of the plant have a bitter taste (this is the meaning of the genus name Marah, which comes from Hebrew.) Despite this, the leaves have been used as a vegetable. The large tuber of the manroot can be processed for a soap-like extract.
Two varieties are recognised, Marah fabaceus var. agrestis (found in the San Francisco bay area and Contra Costa County), and Marah fabaceus var. fabaceus (found elsewhere in California).