Planteværn Online > Skadevoldere - Weed biology<br> <sub>Agro-region: Denmark</sub> - Dead-nettle
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13.7 2020 undefined

Weed biology
Agro-region: Denmark

Dead-nettle Previous page Next page

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Can be mistaken for

Hemp-nettle, which has somewhat larger dicotyledon leaves and true leaves.

Characteristics

Cotyledons
Oval to almost circular with entire leaf margins. A round incision is found at the transition from the cotyledon to the cotyledon stalk. Stalked. Smooth surface. Length approx. 5-6 mm.

True leaves
Heart-shaped with round-toothed leaf margins. Stalked. Hairy surface. Length approx. 10 mm.

Mature plant
As a weed dead-Nettle occurs primarily as two species: red dead-Nettle, where the upper leaves are stalked, and Henbit Dead-nettle, where the upper leaves are unstalked. Both species are relatively small plants with 15-35 cm high, erect, square stems. Length of flower (both species) approx. 10-15 mm. Seed production: Up to approx. 200 seeds per plant.

Seed (both species)
Inverted Beetle-shaped. Dorsal side domed. Ventral side roof-shaped with 2 slightly convex sides and a smaller, triangular top side. Three-sided cross section. Granular, shiny surface. Thousand grain weight: red Dead-nettle approx. 0.9 g and Henbit Dead-nettle approx. 0.6 g.

Biology

Propagation and dispersal
Only through seeds.

Habit
Summer and winter annual.

Importance

Dead-Nettle is frequently found in both autumn- and spring-sown crops throughout Denmark. Dense, overwintering populations can be a hindrance to the early development and tillering of winter crops. In addition, the species can easily both be troublesome and cause losses in open crops.

For treatment options, consult 'Herbicides Across'.
For more options, consult 'Main Menu'.

Taxonomy

Labiatae.

Names in different languages

Danish : Tvetand
German : Taubnessel
English : Dead-nettle
Latin : Lamium spp.
Norwegian : Tvitann
Swedish : Plister

Dead-nettle: Seedling
Seedling
Dead-nettle: Early stage
Early stage
Dead-nettle: Flower <br><i>(Lamium purpureum)</i>
Flower
(Lamium purpureum)
Dead-nettle: Mature plant <br><i>(Lamium purpureum)</i>
Mature plant
(Lamium purpureum)
Dead-nettle: Seeds
Seeds

 
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