Jewelweed

In Great Britain and/or Ireland:
Foodplant / feeds on
epiphyllous, usually infertile pycnidium of Phyllosticta coelomycetous anamorph of Phyllosticta impatientis feeds on live leaf of Impatiens noli-tangere
Remarks: season: 8-9

Plant / resting place / on
puparium of Phytoliriomyza melampyga may be found on leaf of Impatiens noli-tangere

Foodplant / pathogen
sporangium of Plasmopara obducens infects and damages pale green leaf of Impatiens noli-tangere

Foodplant / parasite
Podosphaera balsaminae parasitises Impatiens noli-tangere

Plants annual, 40-70 cm tall. Stem succulent, robust, many branched in upper part, glabrous, lower nodes often swollen with fibrous roots. Leaves alternate, upper leaves shortly petiolate or subsessile; petiole 2-5 cm, slender; leaf blade green abaxially, dark green adaxially, ovate or ovate-elliptic, 3-8 × 1.5-4 cm, both surfaces glabrous, base cuneate or rounded, margin crenate, teeth mucronulate, apex obtuse, rarely acute. Inflorescences 2-4-flowered; peduncles 1-1.5 cm. Pedicels 1.5-2 mm, bracteate above middle; bracts persistent, lanceolate, 3-5 mm, herbaceous. Flowers yellow. Lateral sepals 2, ovate or broadly ovate, 5-6 mm, apex acute. Lower sepal sparsely orange spotted, broadly funnelform, gradually narrowed into an incurved spur 1-1.5 cm. Upper petal orbicular or suborbicular, ca. 1 cm in diam., apex emarginate, rostellate, abaxial midvein green cristate; lateral united petals not clawed, 2-2.5 cm, 2-lobed; basal lobes oblong, small; distal lobes orange spotted at base, broadly dolabriform; auricle narrow. Filaments linear, slightly swollen above; anthers ovoid, apex acute. Ovary erect, fusiform. Capsule linear-cylindric, 1.5-2.5 cm. Seeds many, brown, oblong-globose, 3-4 mm, smooth. Fl. Jul-Sep. 2n = 20.

Anhui, Gansu, Guangdong, Hebei, Heilongjiang, Henan, Hubei, Hunan, Jilin, Liaoning, Nei Mongol, Ningxia, Qinghai, Shaanxi, Shandong, Shanxi, Zhejiang [Japan, Korea, Mongolia, Russia (Far East, Siberia); C and SW Asia, Europe, NW North America].

Forest understories, forest margins, grasslands, along canals; 900-2400 m.

Impatiens occidentalis Rydberg, sp. nov
Impatiens pallida Hook. Fl. Bor. Am. 1: 117, in part. 1830.— Howell, Fl. NW. Am. 1: 111.
1897. Not /. pallida Nutt. 1818. Impatiens Noli-tangere Trel. in A. Gray, Syn. Fl. N. Am. I 1 : 369. 1897. Not /. Noli-langere L,.
1753.
Annual ; stem light-green or straw-colored, about a meter high, glabrous ; petioles 1-5 cm. long ; leaf-blades oval, thin, light-green, 2-10 cm. long, 1-5 cm. wide, acute at the apex, from acute to subcordate at the base, crenate-dentate with obliquely triangular, mucronate teeth, more or less fimbriate-laciniate at the base, with gland-tipped teeth ; inflorescence 3-4 cm. long, 3-5-flowered ; bractsminute, subulate ; lateral sepals obovate, abruptly acuminate, about 6 mm. long; posterior sepal conic-trumpet-shaped, somewhat curved, about 2 cm. long, pale-yellow, unspotted, or with minute dots, gradually tapering into the abruptly recurved spur, which is 8-10 mm. long, cylindric ; petals pale-yellow, the anterior ones broadly obovate, emarginate, 7 mm. long, fully 10 mm. wide ; lateral ones obovate, 7 mm. long, half united with the rounded obovate-spatulate oblique posterior ones, which are nearly 2 cm. long and fully 1 cm. wide ; pod clavate, acute, about 18 mm. long and 4 mm. thick.
Type collected along streams in damp woods, North Fork of Nooksack River, Washington, 1890, W. N. Suksdor/960 (herb. N. Y. Bot. Card.).
Distribution : Damp places from Washington to Alaska.

Impatiens noli-tangere (touch-me-not balsam; Latin impatiēns "impatient" or "not allowing", and nōlī tangere "do not touch": literally "be unwilling to touch") is an annual herbaceous plant in the family Balsaminaceae found in damp places in Europe, Asia and North America. The yellow flowers are followed by pods which forcefully explode when ripe, ejecting the seeds for some distance.

It is also called touch-me-not, yellow balsam, jewelweed, western touch-me-not or wild balsam.

Botanical illustration by Otto Wilhelm Thomé, 1885

Flower closeup