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Persicaria wallichii
HIMALAYAN KNOTWEED


Higher Taxonomy
Family: PolygonaceaeView DescriptionDichotomous Key
Common Name: BUCKWHEAT FAMILY
Habit: Annual to shrub [tree]. Stem: nodes swollen or not. Leaf: simple, basal or cauline, generally alternate; ocreae present or 0, generally scarious, persistent or not. Inflorescence: flower clusters in axillary to terminal cyme-, panicle-, raceme-, spike-, umbel- or head-like arrangements, entire inflorescence or main inflorescence branches generally subtended by bracts ("inflorescence bracts"); peduncles present or 0; flower clusters in Eriogoneae-Eriogonoideae subtended by involucre of >= 1 free or +- fused, sometimes awn-tipped bracts ("involucre bracts") or, in Polygonoideae and rarely in Eriogonoideae, not (if bracts completely fused, involucre "tubular"); pedicels in Eriogoneae each often subtended by 2 free, transparent, linear bractlets or in Polygonoideae all subtended by 2+ fused, membranous, wide bractlets. Flower: generally bisexual, small, 1--200 per node; perianth parts 2--6, generally in 2 whorls, free or basally fused, generally petal-like, often +- concave adaxially, often darker at midvein, often turning +- red or +- brown in age; stamens [1]3 or 6--9 in 2 whorls; ovary superior, 1-chambered, ovule 1, styles 1--3. Fruit: achenes, included in or exserted from perianth, generally 3-angled, ovoid or elliptic, generally glabrous.
Genera In Family: 48 genera, +- 1200 species: worldwide, especially northern temperate; some cultivated for food (Coccoloba, sea-grape; Fagopyrum, Rheum, Rumex) or ornamental (Antigonon, lovechain; Coccoloba; Muehlenbeckia; Persicaria; Polygonum), a few timbered (Coccoloba; Triplaris). Several (Emex; Fallopia; Persicaria; Polygonum; Rumex) are weeds. Note: Treatment of genera in Eriogonoideae based on monographic work of James L. Reveal. Involucre number throughout is number (1--many) per ultimate grouping, at tips of ultimate branches; flower number is per flower cluster or involucre, unless otherwise stated. Fagopyrum esculentum Moench not naturalized, considered an historical waif (or garden weed +- presently), therefore not treated.
eFlora Treatment Author: Mihai Costea, except as noted
Scientific Editor: Thomas J. Rosatti, Bruce G. Baldwin.
Genus: PersicariaView DescriptionDichotomous Key


Common Name: SMARTWEED
Habit: Annual, perennial herb, rhizomed or stoloned. Stem: prostrate to erect, ribbed or +- so or not, glabrous or hairy, generally with adventitious roots. Leaf: cauline, alternate, petioled or not; ocrea papery, rarely +- leaf-like, opaque, persistent or disintegrating, glabrous to variously hairy; blade lanceolate or ovate to hastate or sagittate, entire. Inflorescence: axillary, terminal, generally spike-like; flowers 1--14; peduncle present, pedicels present [or 0]. Flower: bisexual or functionally +- unisexual, base not stalk-like; perianth not or +- enlarging, bell-shaped (urn-shaped, rotate), glabrous, gland-dotted or not, green-white, white, pink, or red; perianth parts 4--5, fused 1/4--2/3, outer 2 > inner 2 or 3; stamens 5--8, filaments free, cylindric, thread-like, glabrous, outer fused to perianth tube or not, anthers elliptic to ovate, yellow, pink, or red; styles 2--3, erect to reflexed, free or fused, stigmas head-like. Fruit: included or exserted, brown or dark-brown to black, not winged, discoid, lens-shaped, or 3-angled. Seed: embryo curved.
Etymology: (Latin: persica, peach, aria, pertaining to; from resemblance of leaves of some species to those of peach)
eFlora Treatment Author: Mihai Costea
Persicaria wallichii Greuter & Burdet
NATURALIZED
Habit: Perennial herb, generally rhizomed, base woody or not. Stem: ascending or erect, 7--12(250) cm, glabrous or densely hairy, +- ribbed; adventitious roots 0. Leaf: ocrea 10--40 mm, cylindric, red-brown, surface glabrous or densely hairy; petiole 0.3--2(3) cm; blade (7.5)9--22(27) cm, 2.8--7.8 cm wide, hairy abaxially, glabrous or hairy adaxially, base cordate to truncate, tip acuminate to acuminate-tailed. Inflorescence: axillary, terminal, panicle-like, 40--120 mm, 10--55 mm wide; peduncle 10--80 mm, glabrous or hairy; bractlets not overlapped; pedicels ascending to spreading, 1--4 mm, glabrous; flowers 3--10. Flower: perianth 2.5--4 mm, rotate, not enlarging, gland-dotted, white or +- pink, lobes 5, oblong to obovate, tips obtuse to rounded; anthers red to purple; styles free. Fruit: included, 2.1--2.5 mm, 1.3--1.8 mm wide, 3-angled, brown, dull, minutely rough (sometimes 0 in California).
Ecology: Moist disturbed places, marshes; Elevation: < 500 m. Bioregional Distribution: NCo (esp Del Norte, Humboldt cos.), n CCo; Distribution Outside California: Oregon, British Columbia; native to south-central Asia. Flowering Time: Aug--Oct
Synonyms: Aconogonon polystachyum (Meisn.) M. Král; Persicaria polystachya (Meisn.) H. Gross, illeg.; Polygonum polystachyum Meisn.
Jepson eFlora Author: Mihai Costea
Index of California Plant Names (ICPN; linked via the Jepson Online Interchange)
Noxious Weed listed on the CDFA Weed Pest Ratings table
View the CDFA Pest Rating page for Persicaria wallichii
Weed listed by Cal-IPC

Previous taxon: Persicaria punctata
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Citation for this treatment: Mihai Costea 2012, Persicaria wallichii, in Jepson Flora Project (eds.) Jepson eFlora, https://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=82467, accessed on April 23, 2024.

Citation for the whole project: Jepson Flora Project (eds.) 2024, Jepson eFlora, https://ucjeps.berkeley.edu/eflora/, accessed on April 23, 2024.

No expert verified images found for Persicaria wallichii.



Geographic subdivisions for Persicaria wallichii:
NCo (esp Del Norte, Humboldt cos.), n CCo
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map of distribution 1
(Note: any qualifiers in the taxon distribution description, such as 'northern', 'southern', 'adjacent' etc., are not reflected in the map above, and in some cases indication of a taxon in a subdivision is based on a single collection or author-verified occurence).





 

Data provided by the participants of the  Consortium of California Herbaria.
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All markers link to CCH specimen records. The original determination is shown in the popup window.
Blue markers indicate specimens that map to one of the expected Jepson geographic subdivisions (see left map). Purple markers indicate specimens collected from a garden, greenhouse, or other non-wild location.
Yellow markers indicate records that may provide evidence for eFlora range revision or may have georeferencing or identification issues.
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CCH collections by month

Duplicates counted once; synonyms included.
Species do not include records of infraspecific taxa, if there are more than 1 infraspecific taxon in CA.
Blue line denotes eFlora flowering time (fruiting time in some monocot genera).