HPIPM:Black nightshade

Taxonomy

Domain	Eukarya
Kingdom	Plantae
Phylum	Magnoliophyta
Class	Magnoliopsida
Superorder	Asteranae
Order	Solanales
Family	Solanaceae
Genus	Solanum

Scientific Name

Solanum nigrum

Common Name

black nightshade

Black nightshade (Solanum nigrum)

Author: The Colorado Department of Natural Resources, Colorado State Parks, and Colorado Natural Areas Program - in partnership with the Division of Plant Industries in the Colorado Department of Agriculture.

Adapted from Appendix 4: Profiles of Colorado State-Listed Noxious Weeds, page 261 by Marjolein Schat, Montana State University

Identification and Life Cycle

Black nightshade (Solanum nigrum), also known as garden nightshade and common nightshade, is an annual or short lived perennial forb in the nightshade family (Solonaceae). Seedlings have ovate leaves that taper to a pointed tip. Stems are smooth and range from 6 to 24 inches tall. Leaves are alternate, ovate, and wavy edged. Flowers are small (0.25 to 0.5 inches), white to pale blue, and occur in clusters. Fruits are green when immature and turn black as they ripen. Black nightshade has a taproot. Black nightshade can be distinguished from the similar species hairy nightshade by the smooth appearance of the stems and leaves.

Habitats

Black nightshade grows in a variety of soils from sandy/gravelly to fertile cultivated soils, although it prefers soils that are high in nitrogen. Black nightshade is commonly found on disturbed soils such as roadsides, rights-of-way, overgrazed rangeland, as well as cultivated fields, flowerbeds, and vegetable gardens.

Impacts

The berries of black nightshade can become mixed with harvested commodities, decreasing crop quality. The berries have been reported to be poisonous to cattle, sheep, goats, pigs, ducks, and chickens. Black nightshade plants form a sticky mass that can plug combine screens and rotors during harvest.

Biology and Ecology

Black nightshade reproduces by seed. Germination begins in spring and continues through the summer. Plants begin to flower by mid-June and berries mature 4 to 5 weeks after flowering occurs. Black nightshade is capable of producing 2,500 to 5,000 seeds per plant. Seeds are dispersed by rodents, birds, livestock, humans, and along water courses. Seeds can remain viable in the soil for more than 5 years.

Biological Control

There are no biological control agents available for this species.

Mechanical and Cultural Control

Mowing, tillage, and hand pulling over the course of several years can help eradicate black nightshade if done prior to seed set.

Chemical Control

There have been reports of black nightshade resistance to photosystem II inhibitors in Europe and New Zealand, but no reports of resistance in the United States. For a complete list of reports of resistance please see http://www.weedscience.org/Summary/USpeciesCountry.asp?lstWeedID=162&FmSpecies=Go

For herbicide recommendations for specific grain rotations and weeds in Montana, please see the MSU Herbicide Chooser Tool.

Examples of herbicides that can be used to manage black nightshade

Consult herbicide labels for additional rate, application, and safety information. Additional herbicide information can be found at http://www.greenbook.net.

Herbicide Active Ingredient trade name	Mode of Action	Product per Acre	Application Time or Growth Stage
Alfalfa
Imazethapyr	Inhibition of acetolacetate synthase ALS (acetohydroxyacid synthase AHAS)
*Pursuit		3- 6 ounces	Apply after seedling alfalfa has reached second trifoliate stage but before weeds reach 3 inches in height.
Dry Beans, Peas, and Lentils
Imazomox	Inhibition of acetolacetate synthase ALS (acetohydroxyacid synthase AHAS)
*Raptor		4 ounces	n dry beans apply when crop has at least one trifoliate leaf and weeds are less than 2 inches tall. In peas apply when crop has at least three pairs of leaves, but before bloom and weeds are 3 inches in height.
Small Grains
Carfentrazone	Inhibition of protoporphyrinogen oxidase (PPO)
*Aim EW		0.5-1.9 ounces	Apply to actively growing weeds prior to jointing in small grains.
Grass Grown for seed
Dicamba; 2,4-D	Action like indole acetic acid (synthetic auxins)
*Weedmaster		0.5-4 pints	Apply at he germinating stage of weeds in seedling grasses. For established grasses, do not apply after the grass reaches the joint stage.
Potato
Metolachlor	Shoot growth inhibitor
*Dual Magnum		1 - 2 pints	Apply pre or post crop emergence.

The information herein is supplied with the understanding that no discrimination is intended and that listing of commercial products, necessary to this guide, implies no endorsement by the authors or the Extension Services of Nebraska, Colorado, Wyoming or Montana. Criticism of products or equipment not listed is neither implied nor intended. Due to constantly changing labels, laws and regulations, the Extension Services can assume no liability for the suggested use of chemicals contained herein. Pesticides must be applied legally complying with all label directions and precautions on the pesticide container and any supplemental labeling and rules of state and federal pesticide regulatory agencies. State rules and regulations and special pesticide use allowances may vary from state to state: contact your State Department of Agriculture for the rules, regulations and allowances applicable in your state and locality.

References

For more information and images please visit IPM Bugwood. http://www.ipmimages.org/search/action.cfm?q=black%20nightshade&Start=1&results=16