Wood Forget-me-not

Myosotis sylvatica Hoffm.

Synonyms -

Family: Boraginaceae

Names:

Myosotis is Greco-Latin meaning mouse ear and refers to the shape of the leaves that resemble ears of a mouse or rat.
Sylvatica
Wood Forget-me-not because the seed heads cling to fur and clothing.

Other Names:

Garden Forget-me-not because it is grown in gardens.

Summary:

A bright blue, spring-summer flowering, hairy, erect or spreading biennial or perennial herb with seed cases that stick to your clothing.

Description:

Cotyledons:

Two.

First leaves:

Form a rosette

Leaves:

Lower leaves form a rosette, upper leaves alternate
Stipules - None.
Petiole - 15-30 mm long.
Blade - Narrow spoon shaped. 20-100 mm long x 8-30 mm wide. Tip rounded. Sides curved and flat. Base tapering. Moderately hairy.
Stem leaves - Alternate. Narrowly oval to oblong or egg shaped. 10- 55 mm long. Short to almost no petiole. Hairy with wart based hairs.

Stems:

To 500 mm long. Many branched. Dense spreading hairs with wart base

Flower head:

Spike, curled like a scorpion tail that uncurls as the flowers mature.

Flowers:

Bright blue with a yellow throat. 5-6 mm long x 6-11 mm diameter.
Ovary - superior
Style - shorter than the stamens.
Calyx - 2.5-4 mm long with five 1-2 mm long lobes. Covered with hooked hairs.
Petals - 5 bright blue, blunt tipped, 6-10 mm long with a yellow throat or occasionally white. Tubular
Stamens - Included in the tube alternate with the corolla lobes
Anthers -

Fruit:

Pale to dark brown capsule, 2 mm long with tiny hooked hairs.

Seeds:

Black

Roots:

Taproot.

Key Characters:

Cotyledons flattish and broader than the short radicle.
Hairs on leaves spreading
Corolla regular with scales in the throat
Corolla usually bright blue with a yellow throat.
Corolla lobes >2 mm long.
Hairs on calyx spreading and hooked.
Bracts absent
Ovary deeply lobed
Style inserted between the lobes and almost basal.
Filaments very short
Anthers enclosed in corolla tube, without terminal awns
Torus almost flat
4 erect nutlets attached by a basal, flat areole
Nutlets smooth on both faces, biconvex.
Seeds without albumen.
Adapted from P. Wilson, J. Black and N. Burbidge.

Biology:

Life cycle:

Biennial or short lived perennial herb.
Germinates mainly in autumn and forms a rosette of leaves up to 300 mm diameter in open areas or quickly elongates with scrambling stems in more dense vegetation. Flowers in spring.

Physiology:

Drought tolerant.
Frost tolerant to -200C.
Tolerates temporary waterlogging.
Very plastic growth with plants down to 50 mm tall being able to set some seed.
Susceptible to powdery mildew especially in dry conditions.

Reproduction:

By seed.

Flowering times:

September to December in WA.
September to March in Victoria.
Spring to summer.
March to November in New Zealand.

Seed Biology and Germination:

Produces large amounts of seed.
Germinates at any time of year that moisture is present and has a large germination in autumn.
Prefers disturbed areas for establishment.

Vegetative Propagules:

None, but regrows from the base when broken.

Hybrids:

'Blue Ball' is a garden cultivar.

Allelopathy:

Population Dynamics and Dispersal:

Spread by attaching to animals, water, garden refuse and contaminated soil.
Often sold in nurseries and as seed and very often a component of seed packets labelled "wildflower mixes".

Origin and History:

Native to Europe and Asia.

Distribution:

ACT, NSW, SA, TAS, VIC, WA.
Jarrah forest area of WA.
NZ, USSR.

Courtesy Australia's Virtual Herbarium.

Habitats:

Prefers shady places but will grow in full sun.
Damp and wet sclerophyll forests, riparian areas.
Often associated with Lyre Bird mounds or other disturbed areas.

Climate:

Temperate

Soil:

Loam over granite and creek lines.

Plant Associations:

Coastal vegetation.
Inter tussock spaces in grasslands.

Significance:

Beneficial:

Ornamental

Detrimental:

Weed of wet areas, creek lines, plantations, orchards, forest edges, roadsides, gardens

Toxicity:

None recorded.

Symptoms:

Treatment:

Legislation:

None.

Management and Control:

Metribuzin provides good control post emergence.
Spraying with hormone or sulfonylurea herbicides or cultivation is expected to give control. Hand weeding is difficult because it tends to break off.

Thresholds:

Eradication strategies:

Metribuzin has given very good post emergent control at low rates in trials.
Apply 20 g/ha chlorsulfuron 750g/kg with 0.25% wetting agent in early winter each year for 3 years.

Herbicide resistance:

Biological Control:

Attacked by Powdery Mildew.

Related plants:

Myosotis arvensis
Myosotis australis is a native plant has smaller white or yellow flowers and tends to be in Peppermint woodland. Its corolla lobes are <2 mm long and much smaller than Myosotis sylvatica. The lobes of the fruiting calyx are triangular and twice as long as broad.
Myosotis discolor has white or yellow flowers turning blue and the corolla lobes are <2 mm and much smaller than Myosotis sylvatica. The lobes of the fruiting calyx are narrow and triangular to linear being 2.5 to 3 times longer than broad. Naturalised at Cowaramup and Bridgetown and is a significant weed of water courses in the Porongorup National Park in WA. It appears to be more tolerant of metribuzin than M. sylvatica.
Myosotis laxa ssp. caespitosa
Myosotis scorpioides
Myosotis stricta

Plants of similar appearance:

Heliotrope (Heliotropium species)
Australian Hound's Tongue (Cynoglossum australe) is a native species.

References:

Black, J.M. (1965). Flora of South Australia. (Government Printer, Adelaide, South Australia). P417. Diagram.

Blood, K. (2001). Environmental weeds: a field guide for SE Australia. (CH Jerram & Associates, Australia). P154-155. Photo.

Bodkin, F. (1986). Encyclopaedia Botanica. (Angus and Robertson, Australia).

Burbidge, N.T. and Gray, M. (1970). Flora of the Australian Capital Territory. (Australian National University Press, Canberra). P309. Diagram.

Cunningham, G.M., Mulham, W.E., Milthorpe, P.L. and Leigh, J.H. (1992). Plants of Western New South Wales. (Inkata Press, Melbourne).

Everist, S.L. (1974). Poisonous Plants of Australia. (Angus and Robertson, Sydney).

Harden, Gwen J. (1991). Flora of NSW. (Royal Botanic Gardens, Sydney). Volume 3. P394. Diagram.

Hussey, B.M.J., Keighery, G.J., Cousens, R.D., Dodd, J. and Lloyd, S.G. (1997). Western Weeds. A guide to the weeds of Western Australia. (Plant Protection Society of Western Australia, Perth, Western Australia). P112.

Lazarides, M. and Cowley, K. and Hohnen, P. (1997). CSIRO handbook of Australian Weeds. (CSIRO, Melbourne). 681.6.

Paczkowska, G. and Chapman, A. (2000). The Western Australia flora: a descriptive catalogue. (Wildflower Society of Western Australia (Inc), the Western Australian Herbarium, CALM and the Botanic Gardens & Parks Authority). P185.

Randall, J.M. and Marinelli, J. (1996) Invasive Plants. (Brooklyn Botanic Gardens Inc. Brooklyn). P. Photo.

Roy, B., Popay, I., Champion, P., James, T. and Rahman, A. (1998). An Illustrated Guide to Common Weeds of New Zealand. (New Zealand Plant Protection Society). P105. Photo

Acknowledgments:

Collated by HerbiGuide. Phone 08 98444064 or www.herbiguide.com.au for more information.