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Iris douglasiana - Herb.

Mountain Iris

Author	Herb.	Botanical references	71, 200, 270
Family	Iridaceae	Genus	Iris
Synonyms
Known Hazards	Many plants in this genus are thought to be poisonous if ingested, so caution is advised[65]. The roots are especially likely to be toxic[238]. Plants can cause skin irritations and allergies in some people[238].
Range	South-western N. America - California and Oregon.
Habitat	Open woods, grassy slopes, fields and open places[71, 270] on a wide range of soil types.[129]
Edibility Rating	0 (1-5)	Medicinal Rating	0 (1-5)

Physical Characteristics

An evergreen Perennial growing to 0.3m by 0.6m.

The plant prefers light (sandy) and medium (loamy) soils. The plant prefers acid, neutral and basic (alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It requires dry moist or wet soil and can tolerate drought. The plant can tolerate maritime exposure.

Habitats

Woodland Garden; Sunny Edge; Dappled Shade; Ground Cover; Bog Garden;

Edible Uses

None known

Medicinal Uses

Plants For A Future can not take any responsibility for any adverse effects from the use of plants. Always seek advice from a professional before using a plant medicinally.

None known

Other Uses

Fibre; Ground cover; Paper.

A fibre is obtained from the leaves. Traditionally the N. American Indians would take just the one outside fibre from each side of a leaf. This must have necessitated using a huge number of leaves. It makes a beautifully strong and pliable cord or rope[92, 207]. It would take a person almost 6 weeks to make a rope 3.5 metres long[207]. The fibre can also be used for making paper[189] The leaves are harvested in summer after the plant has flowered, they are scraped to remove the outer skin and are then soaked in water for 2 hours prior to cooking. The fibres are cooked for 24 hours with lye and then beaten in a ball mill for 3 hours. They make a light tan paper[189]. Plants can be grown for ground cover when spaced about 60cm apart each way[208].

Cultivation details

We have found this species to be exceedingly easy to grow in sun or shade in our medium loamy soil that is slightly acid. It does well in very wet as well as very dry years. It has withstood considerable neglect, forming a very dense clump that seems capable of standing up to grass and other vigorous plants[K]. The following notes, however, suggest a wide difference of opinions over the best conditions for this plant[K]. Requires a rich well-drained lime-free soil[42, 71, 79]. Another report says that it succeeds in sun or shade in acid or slightly alkaline soils[129]. Requires a moist soil, growing well by water[1]. This species requires a really well-drained soil, dry rather than damp[233]. It succeeds in dry shade according to another report which also says that it is drought tolerant once established[190]. Easily grown in semi-shade in a woodland soil[42]. Tolerates salt spray[129]. Plants are hardy to about -15°c[187]. A very variable and ornamental plant[1, 270], it hybridizes readily, especially with other Pacific coast Irises[129]. Iris douglasiana hybridizes with I. bracteata, I. chrysophylla, I. fernaldii, I. hartwegii, I. innominata, I. macrosiphon, I. munzii, I. purdyi, I. tenax, and I. tenuissima[270]. Members of this genus are rarely if ever troubled by browsing deer or rabbits[233]. Resents root disturbance, any moving of the plant is best done in early September[129].

Propagation

Seed - best sown as soon as it is ripe in a cold frame. Stored seed should be sown as early in the year as possible in a cold frame. Prick out the seedlings into individual pots when they are large enough to handle and grow them on in the greenhouse or cold frame for their first year. Plant out into their permanent positions in late spring or early summer. Division, best done after flowering in late summer[42]. Very easy, larger clumps can be replanted direct into their permanent positions, though it is best to pot up smaller clumps and grow them on in a cold frame until they are rooting well. Plant them out in the spring.

Links

This plant is also mentioned in the following PFAF articles: Fiber Plants.

References

[K] Ken Fern
Notes from observations, tasting etc at Plants For A Future and on field trips.

[1] F. Chittendon. RHS Dictionary of Plants plus Supplement. 1956 Oxford University Press 1951
Comprehensive listing of species and how to grow them. Somewhat outdated, it has been replaces in 1992 by a new dictionary (see [200]).

[42] Grey. C. H. Hardy Bulbs. Williams & Norgate. 1938
Rather dated now, but an immense work on bulbs for temperate zones and how to grow them. Three large volumes.

[65] Frohne. D. and Pfänder. J. A Colour Atlas of Poisonous Plants. Wolfe 1984 ISBN 0723408394
Brilliant. Goes into technical details but in a very readable way. The best work on the subject that I've come across so far.

[71] Munz. A California Flora. University of California Press 1959
An excellent flora but no pictures. Not for the casual reader.

[79] Innes. C. The World of Iridaceae 0
Deals with many of the plants in the Iris family giving brief details of habitat and notes on cultivation. Well illustrated.

[92] Balls. E. K. Early Uses of Californian Plants. University of California Press 1975 ISBN 0-520-00072-2
A nice readable book.

[129] ? Alpine Garden Society Bulletin. Volume 56. Alpine Garden Society 0
Excerpts from the periodical. Some details on Corydalis spp.

[187] Phillips. R. & Rix. M. Perennials Volumes 1 and 2. Pan Books 1991 ISBN 0-330-30936-9
Photographs of over 3,000 species and cultivars of ornamental plants together with brief cultivation notes, details of habitat etc.

[189] Bell. L. A. Plant Fibres for Papermaking. Liliaceae Press 1988
A good practical section on how to make paper on a small scale plus details of about 75 species (quite a few of them tropical) that can be used.

[190] Chatto. B. The Dry Garden. Dent 1982 ISBN 0460045512
A good list of drought resistant plants with details on how to grow them.

[200] Huxley. A. The New RHS Dictionary of Gardening. 1992. MacMillan Press 1992 ISBN 0-333-47494-5
Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.

[207] Coffey. T. The History and Folklore of North American Wild Flowers. Facts on File. 1993 ISBN 0-8160-2624-6
A nice read, lots of information on plant uses.

[208] Thomas. G. S. Plants for Ground Cover J. M. Dent & Sons 1990 ISBN 0-460-12609-1
An excellent detailled book on the subject, very comprehensive.

[233] Thomas. G. S. Perennial Garden Plants J. M. Dent & Sons, London. 1990 ISBN 0 460 86048 8
A concise guide to a wide range of perennials. Lots of cultivation guides, very little on plant uses.

[238] Bown. D. Encyclopaedia of Herbs and their Uses. Dorling Kindersley, London. 1995 ISBN 0-7513-020-31
A very well presented and informative book on herbs from around the globe. Plenty in it for both the casual reader and the serious student. Just one main quibble is the silly way of having two separate entries for each plant.

[270] Flora of N. America 0
An on-line version of the flora with an excellent description of the plant including a brief mention of plant uses.

Readers Comments

Plants for a Future does not verify the accuracy of reader comments, use at your own risk. In particular Plants For A Future can not take any responsibility for any adverse effects from the use of plants. You should always consult a professional before using plants medicinally.

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