Armoracia rusticana

The roots of Horseradish (Armoracia rusticana), a member of the mustard family (Brassicaceae=Cruciferae), are crushed, minced, or powdered to produce the familiar spicy off-white condiment. As in other mustards, the pungent compounds are isothiocyanates. Horseradish is a perennial herb with a long, yellowish buff taproot bearing long-stalked ovate or oblong leaves (30 to 60 cm in length) with coarsely toothed, wavy margins. The species probably originated in southeastern Europe and western Asia, but has long been widely cultivated in Europe as well as North America and the hilly regions of India.

(Vaughan and Geissler 1997)

Horseradish has been cultivated for its root for over 2,000 years. Today, commercial production occurs mainly in North America (led by the State of Illinois; Walters and Wahle 2010) and Europe. Armoracia rusticana is propagated exclusively vegetatively. Like many vegetatively propagated crops, cultivated A. rusticana plants are generally sterile. This species is not known to occur in the wild, although the two other species in the genus, A. macrocarpa and A. sisymbrioides do occur in the wild and reproduce by seed.

(Sampliner et al. 2009)

Production from Horseradish roots of peroxidase (a heme-containing enzyme that utilizes hydrogen peroxide to oxidize a wide variety of organic and inorganic compounds) occurs on a relatively large scale because of the commercial uses of the enzyme, e.g., as a component of clinical diagnostic kits and for immunoassays (Veitch 2004).

This perennial wildflower develops a rosette of basal leaves, from which there develops one or more flowering stalks about 1¾-4' tall. The blades of the basal leaves are ½-2' long and 1½-6" across; they are broadly oblong-elliptic in shape and finely crenate-serrate along their margins. The petioles of the basal leaves are often as long as the blades. The basal leaves are widely spreading and rather floppy; their margins often undulate up-and-down. The stems of Horseradish are light to medium green and glabrous. Alternate leaves become smaller in size as they ascend these stems; their blades are 1-6" long and ¼-2" across. The blades of alternate leaves are narrowly elliptic to broadly oblong-lanceolate in shape and their margins are coarsely crenate-serrate to shallowly pinnatifid; they are sessile or with short petioles. The upper blade surfaces of both basal and alternate leaves are medium to dark green and glabrous, while their lower surfaces are a more pale shade of green and glabrous below. The central stem and upper axillary stems terminate in either racemes or panicles of flowers about 4-16" in length. The flowers bloom toward the apex of each raceme (or branch of a panicle), while seedpods develop below. Each flower spans about 1/3" (8 mm.) across, consisting of 4 white petals, 4 light green sepals, 6 stamens, and a pistil with a short style. The petals are about twice the length of the sepals. The ascending pedicels are ¼-¾" in length, light green, and glabrous, becoming longer as the seedpods develop. The central stalks and branches of the racemes and panicles are light green and glabrous. The blooming period can occur from mid-spring to mid-summer and lasts about 2 months. The flowers are replaced by cylindrical seedpods up to ¼" (6 mm.) long; each seedpod can contain up to 8 seeds. The root system consists of a stout taproot and stout rhizomes. Clonal colonies of plants are often produced.

The non-native Horseradish is occasional in most areas of Illinois, except in the SE section of the state, where it is rare or absent (see Distribution Map). This plant was introduced into North America from Europe during colonial times; it is native to SE Europe and parts of SW Asia. Habitats include streambanks, ditches, fence rows, low areas along roads and railroads, abandoned fields, vacant lots, disturbed open woodlands, and waste areas. Horseradish is still cultivated in gardens as a culinary herb. It is usually found in disturbed areas.

Armoracia armoracia (L.) Cockerell:
Canada (North America)
United States (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Armoracia lapathifolia Gilib.:
Canada (North America)
Honduras (Mesoamerica)
United States (North America)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

Armoracia rusticana G. Gaertn., B. Mey. & Scherb.:
Canada (North America)
United States (North America)
China (Asia)

Note: This information is based on publications available through Tropicos and may not represent the entire distribution. Tropicos does not categorize distributions as native or non-native.

A. rusticana occurs in Latvia; Lithuania; Estonia; Kaliningrad; east, north, northwest, south and central European Russia; Belarus; Moldova; and Ukraine (including Crimea) (Smekalova 2008).

Canada

Origin: Exotic

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

United States

Origin: Exotic

Regularity: Regularly occurring

Currently: Unknown/Undetermined

Confidence: Confident

Herbs with fusiform or cylindric, fleshy or woody roots. Stems 50-120(-200) cm tall. Basal leaves few; petiole to 60 cm, broadly expanded at base; leaf blade broadly oblong, oblong-lanceolate, or ovate, (10-)20-45(-60) × (3-)5-12(-17) cm, coarsely crenate or rarely pinnatifid. Lower and middle cauline leaves shortly petiolate, pinnatifid or pinnatisect, with oblong to linear-oblong lobes, smaller than basal leaves; upper cauline leaves sessile or shortly petiolate, linear to linear-lanceolate, base cuneate or attenuate, margin serrate, crenate, or rarely entire. Fruiting pedicels ascending, slender, 0.8-2 cm. Sepals ovate, 2-4 mm. Petals obovate or oblanceolate, 5-7(-8) mm; claw to 1.5 mm. Filaments 1-2.5 mm; anthers ovate, 0.5-0.8 mm. Ovules 8-12 per ovary. Mature fruit rarely produced, ovate, oblong, or suborbicular, 4-6 mm, few seeded; style obsolete or to 0.5 mm; stigma capitate, well developed. Seeds not seen. Fl. May-Jul. 2n = 32.

Armoracia sativa Bernhardi; Cochlearia armoracia Linnaeus; Nasturtium armoracia (Linnaeus) Fries; Rorippa armoracia (Linnaeus) A. S. Hitchcock; R. rusticana (G. Gaertner et al.) Godron.

The non-native Horseradish is occasional in most areas of Illinois, except in the SE section of the state, where it is rare or absent (see Distribution Map). This plant was introduced into North America from Europe during colonial times; it is native to SE Europe and parts of SW Asia. Habitats include streambanks, ditches, fence rows, low areas along roads and railroads, abandoned fields, vacant lots, disturbed open woodlands, and waste areas. Horseradish is still cultivated in gardens as a culinary herb. It is usually found in disturbed areas.

Habitat and Ecology

Systems

• Terrestrial

Cultivated and naturalized. Hebei, Heilongjiang, Jilin, Jiangsu, Liaoning [native to Europe; cultivated and naturalized elsewhere].

The nectar and pollen of the flowers attract small bees, flies, small butterflies, and probably other insects. Several leaf beetles (Chrysomelidae) have been observed to feed on Horseradish, specifically

In Great Britain and/or Ireland:
Foodplant / spot causer
pycnidium of Ascochyta coelomycetous anamorph of Ascochyta armoraciae causes spots on live leaf of Armoracia rusticana
Remarks: season: 7-10

Foodplant / open feeder
gregarious larva of Athalia rosae grazes on leaf (underside) of Armoracia rusticana
Other: major host/prey

Foodplant / spot causer
Cercospora dematiaceous anamorph of Cercospora armoraciae causes spots on live leaf of Armoracia rusticana
Remarks: season: 9-10

Foodplant / saprobe
colony of Dendryphion dematiaceous anamorph of Dendryphion comosum is saprobic on dead Armoracia rusticana
Remarks: season: 1-12

Foodplant / parasite
Erysiphe cruciferarum parasitises live Armoracia rusticana

Foodplant / sap sucker
adult of Eurydema oleracea sucks sap of Armoracia rusticana

Foodplant / saprobe
superficial, scattered on in small groups, thinly subiculate perithecium of Hydropisphaera arenula is saprobic on dead stem of Armoracia rusticana
Remarks: season: 1-12

Foodplant / pathogen
Leptosphaeria maculans infects and damages live Armoracia rusticana

Foodplant / parasite
colony of sporangium of Peronospora parasitica parasitises live Armoracia rusticana

Foodplant / open feeder
larva of Phaedon cochleariae grazes on live leaf of Armoracia rusticana
Remarks: season: -early 9

Foodplant / shot hole causer
amphigenous colony of Ramularia hyphomycetous anamorph of Ramularia armoraciae causes shot holes on live leaf of Armoracia rusticana
Remarks: season: 7-10
Other: major host/prey

Foodplant / spot causer
punctiform, pallid, central pycnidium of Septoria coelomycetous anamorph of Septoria armoraciae causes spots on live leaf of Armoracia rusticana
Remarks: season: 7-10

Foodplant / pathogen
colony of Thielaviopsis dematiaceous anamorph of Thielaviopsis basicola infects and damages Armoracia rusticana

Foodplant / saprobe
effuse colony of Torula dematiaceous anamorph of Torula herbarum is saprobic on dead Armoracia rusticana

Foodplant / pathogen
Turnip Mosaic virus infects and damages live, stunted leaf of Armoracia rusticana
Remarks: season: Summer

The following is a representative barcode sequence, the centroid of all available sequences for this species.

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 8
Specimens with Barcodes: 9
Species With Barcodes: 1

Year Assessed

Assessor/s

Reviewer/s

Contributor/s

Justification

Rounded Global Status Rank: GNR - Not Yet Ranked

Canada

Rounded National Status Rank: NNA - Not Applicable

United States

Rounded National Status Rank: NNA - Not Applicable

Population

Population Trend

Major Threats

These species are introduced in Switzerland.

Conservation Actions

The preference is full or partial sun, moist conditions, and fertile soil containing loam or silt-loam. Because of its underground rhizomes, Horseradish can spread aggressively.