Thanks, John, for your thoughts on this.  I'm hoping to get a little discussion going on this topic, as I wonder if some of our current thinking on invasive species and native plants might not be worth a second look from a permaculture point of view.  
 
With climate change, the range of our native species is already shifting and in our permaculture and garden designs we'll be needing to include species that can perform many functions for us, including vigor and edibility.  Here in our area, the native species would probably not feed the current population even if the climate were stable, so looking around for permaculture-friendly species is, I think, a worthwhile endeavor. 
 
Of course iceplant may not pass the tests of desirability, but so far apart from the idea that it might displace native species, I've not heard too many good arguments against it apart from criticisms of its taste.  My own research found that one could make "delicious" jam from  its fruits -- is this not true?  Also apparently some species of iceplant are more tasty than others, so as with any edible plant, we'd need to select for taste.
 
If iceplant isn't the succulent of choice (and in our increasingly dry climate we definitely can use some succulents for various purposes, including living, moisture-retaining mulch), can someone recommend another succulent that is edible and easy to grow?
 
I was especially intrigued with the idea of using it for green roots because of its shallow roots.  If nothing else, it might offer excellent insulation, and on a roof it certainly isn't displacing native plants!
 
Thanks for the good discussion,
 
Linda
 
In a message dated 9/6/2009 2:30:34 A.M. Pacific Daylight Time, johnvalenzuela@hotmail.com writes:
Linda, your useful information and propositions concerning iceplant have really got me going on a little rant here!

Iceplant is barely edible to me, definitely not a 'good edible permaculture plant'. Our grandparents may have found iceplant quite useful, but many of them were not aware of the value of native plants in thier ethnobotanical and wildlife habitat functions, as many of us are still not aware of today.

Wow! With all the useful, uniquely native, and other relatively non-invasive plants to promote, are we entertaining the idea of planting something that we all have all observed spreading locally and creating huge monocultures, even taking over some relatively stable native coastal plant communities? OK, it may be a very interesting and useful plant, but it doesn't mean we have to plant it, to use it- Don't we have enough of it to use already? From my perspective, planting iceplant would be a lazy choice. For others, do the cost/benefit analysis and compare to other plant options (and combinations) to see what your best choices might be.

from the website you linked to (http://www.plantzafrica.com/plantcd/carpobed.htm):
Conservation status
Carpobrotus edulis is not regarded as threatened in its native habitat, but it is invading natural areas in other parts of the world and threatening the survival of other species. In California, where it has been used since the early 1900s to stabilize the soil along railway tracks and roadsides and as a garden ornamental, it has naturalized and is invading coastal vegetation from north of Eureka to Rosarita Bay. It is known as the highway ice plant in the USA.

from another source:
There is evidence that iceplant also competes indirectly with native species. It has been reported that iceplant can lower soil pH and also affect the root morphology of some native shrubs (D'Antonio, 1990a; D'Antonio and Mahall, 1991). It is also possible, because iceplant does not seem to be palatable to most native herbivores, that its presence could increase browsing pressure on native flora and influence the species composition of herbivorous fauna. (3) Invasion by the alien succulent, C. edulis , has become a common occurrence after fire in maritime chaparral

also see:
(http://www.cal-ipc.org/ip/management/ipcw/pages/detailreport.cfm@usernumber=25&surveynumber=182.php)

I am definitely not suggesting that I only use natives in my plantings, but come on! Let's be a little more creative than planting something that can actually lower bio-diversity, like ice plant does!

Now having gotten all that out, Thank you for all the useful information on iceplant, as I am actually quite interested in the many uses of locally invasive (well adapted), or overly planted, seemingly useless landscape plants, (such as Agapanthus, or the various shrubs known as Broom). Considering all the qualities that were noted, perhaps it's economic values can be used as an incentive to harvest and remove it, to fund replacement with a more diverse, locally unique, and productive assembly of plants. If the plant selection criteria is to have some fire resistant, good tasting fruit and medicinal uses, how about some diversity plantings, starting with native prickly pear and some Aloe spp., Agave spp., and so many others. . .?   Rather than more of the same old-monoculture, lets plan for more diversity and complexity of relationships!

be fruitful-
John V.



Cornucopia Kitchen Gardens and Food Forests
John Valenzuela Permaculture Services
Horticulturist, Consultant, Educator-
California, Hawai'i  phone: (415) 246-8834
e-mail: johnvalenzuela@hotmail.com




From: LBUZZELL@aol.com
Date: Fri, 4 Sep 2009 14:34:14 -0400
To: Scpg@arashi.com; sbperm2006@googlegroups.com; sbogc@yahoogroups.com; sbfoodfuture@googlegroups.com
Subject: [Scpg] is ice plant a good edible permaculture plant?

Iceplant (Carpobrotus edulis aka Hottentot Fig) has a bad reputation in California these days, although its usefulness was much valued by our grandparents' generation.  It's an attractive, low-growing groundcover plant now considered invasive and governments are spending a lot of money ripping it out and replacing it with native plants.
 
But perhaps from a permaculture point of view it's worth another look? It's an amazing plant that performs multiple useful functions.
  • Yields an edible fruit which has been eaten by humans since archeological times. Fruit is fleshy, 35 mm in diameter, shaped like a spinning top, on a winged stalk, becoming yellow and fragrant when ripe. The outer wall of the fruit becomes yellowish, wrinkled and leathery with age. The seeds are embedded in the sticky, sweet, jelly-like mucilage. The fruits can be eaten fresh and they have a strong, astringent, salty, sour taste. They are not as tasty as those of C. acinaciformis (purple iceplant, can be used to make delicious jam) and C. deliciosus (purple or pink iceplant) which are sweeter. See http://www.plantzafrica.com/plantcd/carpobed.htm 
  • Edible by some wildlife as well. Flowers draw bees and are also eaten by animals. In S. Africa, leaves are eaten by tortoises.
  • Holds water and thus is an effective fire-resistant barrier around house or in foothills in fire-prone areas.
  • Drought tolerant
  • A coastal plant
  • Low maintenance. Vigorous and will grow where little else wants to grow
  • Wind resistant
  • Controls erosion by binding hillsides, stabilizing sandy dunes.
  • Shallow-rooting so good for roof gardens
  • Like most succulents, a useful "living mulch" groundcover.
  • "Can be planted on flat, sandy ground, on loose sand dunes, gravelly gardens, lime-rich and brackish soils as well as in containers, rockeries, embankments and will cascade over terrace walls." 
  • Pretty yellow flowers and attractive rusty coloration even when not in bloom (you can see its autumnal-toned beauty in many paintings of coastal California scenes).
  • Has medicinal uses and is a first-aid plant. "The leaf juice is astringent and mildly antiseptic. It is mixed with water and swallowed to treat diarrhea, dysentery and stomach cramps, and is used as a gargle to relieve laryngitis, sore throat and mouth infections. Chewing a leaf tip and swallowing the juice is enough to ease a sore throat. Leaf juice or a crushed leaf is a famous soothing cure for blue-bottle stings - being a coastal plant it is luckily often on hand in times of such emergencies. The leaf juice is used as a soothing lotion for burns, bruises, scrapes, cuts, grazes and sunburn, ringworm, eczema, dermatitis, sunburn, herpes, nappy rash, thrush, cold sores, cracked lips, chafing, skin conditions and allergies...The leaf juice also relieves the itch from mosquito, tick and spider bites both for people and their animal companions. In the Eastern Cape of South africa it is also used to treat diabetes and diptheria."
So what do you think?  It is worth another look?  Could this be a useful plant for various garden and permaculture designs? Or should it be shunned as uncontrollable?
 
Linda


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