''Solidago canadensis'', known as Canada goldenrod or Canadian goldenrod, is an
herbaceous
Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials.
Definitions of "herb" and "herbaceous"
The fourth edition of ...
perennial plant of the family
Asteraceae
Asteraceae () is a large family (biology), family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the Order (biology), order Asterales. The number of species in Asteraceae is rivaled only by the Orchi ...
. It forms colonies of upright growing plants, with many small yellow flowers in a branching
inflorescence
In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...
held above the foliage. It is native to northeastern and north-central North America and is an
invasive plant
An invasive species is an introduced species that harms its new environment. Invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native speci ...
in other parts of the continent and several areas worldwide, including Eurasia.
Description
''Solidago canadensis'' is a herbaceous
perennial
In horticulture, the term perennial ('' per-'' + '' -ennial'', "through the year") is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than 2 years. The term is also ...
plant with stems that grow and sometimes to tall. It has a wide distribution with several varieties, which have significant variability. The lanceolate to broadly linear shaped leaves are alternately arranged on the stems. The leaves are long and wide. The stems have lines of white hairs, while the undersides of the leaves are pubescent. The leaves are often prominently toothed. The flowers have yellow rays and are arranged into small heads on branched pyramidal shaped inflorescences, flowering occurs from July to October. It has a
rhizomatous
In botany and dendrology, a rhizome ( ) is a modified subterranean plant stem that sends out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow hori ...
growth habit, which can produce large colonies of clones.
Distribution, habitat and ecology
''Solidago canadensis'' is native to northeastern and north-central North America. It is winter hardy in USDA
hardiness zone
A hardiness zone is a geographic area defined as having a certain average annual minimum temperature, a factor relevant to the survival of many plants. In some systems other statistics are included in the calculations. The original and most widely ...
s 3–9. It is found in a variety of habitats. It typically is one of the first plants to colonize an area after a disturbance (such as fire) and rarely persists once shrubs and trees become established. It is found in very dry locations (e.g. road sides) and also waterlogged ones (e.g. moist thickets).
Canada goldenrod is visited by a wide variety of insects for its pollen and nectar, including bees, wasps, flies, beetles, butterflies, and moths. It is especially strongly favored as a nectar source by bumblebees and paper wasps, such as '' Polistes parametricus'' and ''P. fuscatus''. Aside from wasps, it is also visited frequently by honeybees and some butterflies, such as
monarchs
A monarch () is a head of stateWebster's II New College Dictionary. "Monarch". Houghton Mifflin. Boston. 2001. p. 707. for life or until abdication, and therefore the head of state of a monarchy. A monarch may exercise the highest authority an ...
.
''Solidago canadensis'' is sometimes browsed by deer and is good to fair as food for domestic livestock such as cattle or horses.
It can be extremely aggressive and tends to form monocultures and near-monocultures in parts of its native range, such as in southwest
Ohio
Ohio ( ) is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. It borders Lake Erie to the north, Pennsylvania to the east, West Virginia to the southeast, Kentucky to the southwest, Indiana to the ...
clay loam. It not only seeds a great deal, but also spreads rapidly via running rhizomes. Its root system is very tough, and plants that have been pulled out of the ground prior to freezing and left exposed atop soil have survived winter temperatures down to -26 °C (-14 °F).
Galls
Many wasps form parasitic galls inside the stem of goldenrod. There are stem, flower, and bud galls. This species is host to the following insect induced galls:
* '' Asteromyia carbonifera'' (Osten Sacken, 1862)
* '' Asteromyia tumifica'' (Beutenmuller, 1907)
* '' Epiblema scudderiana'' (Clemens, 1860)
* ''
Eurosta solidaginis
The goldenrod gall fly (''Eurosta solidaginis''), also known as the goldenrod ball gallmaker, is a species of fly native to North America. The species is best known for the characteristic galls it forms on several species in the '' Solidago'', o ...
Rhopalomyia solidaginis
''Rhopalomyia solidaginis'', the goldenrod bunch gall, is a species of gall midges, insects in the family Cecidomyiidae. The galls of this species have the following host species of goldenrods: ''Solidago altissima'', ''Solidago canadensis'', an ...
invasive weed
An invasive species is an introduced species that harms its new environment. Invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native species ...
in many parts of
Europe
Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...
,
Japan
Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
and
China
China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
.
In eastern and southeastern China, particularly the provinces of
Jiangsu
Jiangsu is a coastal Provinces of the People's Republic of China, province in East China. It is one of the leading provinces in finance, education, technology, and tourism, with its capital in Nanjing. Jiangsu is the List of Chinese administra ...
Shanghai
Shanghai, Shanghainese: , Standard Chinese pronunciation: is a direct-administered municipality and the most populous urban area in China. The city is located on the Chinese shoreline on the southern estuary of the Yangtze River, with the ...
, its invasion has caused widespread concern. Local news reported that the spread of invasive plants including Canada goldenrod has caused the local extinction of 30 native plants in
Shanghai
Shanghai, Shanghainese: , Standard Chinese pronunciation: is a direct-administered municipality and the most populous urban area in China. The city is located on the Chinese shoreline on the southern estuary of the Yangtze River, with the ...
, as of 2004. According to the
CCTV
Closed-circuit television (CCTV), also known as video surveillance, is the use of closed-circuit television cameras to transmit a signal to a specific place on a limited set of monitors. It differs from broadcast television in that the signa ...
program ', it has reduced orange harvests in
Ningbo
Ningbo is a sub-provincial city in northeastern Zhejiang province, People's Republic of China. It comprises six urban districts, two satellite county-level cities, and two rural counties, including several islands in Hangzhou Bay and the Eas ...
. It is still spreading across China, and sightings have been reported in as far as
Yunnan
Yunnan; is an inland Provinces of China, province in Southwestern China. The province spans approximately and has a population of 47.2 million (as of 2020). The capital of the province is Kunming. The province borders the Chinese provinces ...
province. Eradication attempts are still underway as of 2021. Confusion with native ''Solidago'' species is a concern.
Use and importance
It is grown as an
ornamental plant
Ornamental plants or ''garden plants'' are plants that are primarily grown for their beauty but also for qualities such as scent or how they shape physical space. Many flowering plants and garden varieties tend to be specially bred cultivars th ...
in flower gardens.
It is sometimes blamed for causing
hay fever
Allergic rhinitis, of which the seasonal type is called hay fever, is a type of rhinitis, inflammation in the nose that occurs when the immune system overreacts to allergens in the air. It is classified as a Allergy, type I hypersensitivity re ...
, which is actually caused by simultaneously blooming
ragweed
Ragweeds are flowering plants in the genus ''Ambrosia'' in the aster family, Asteraceae. They are distributed in the tropical and subtropical regions of the Americas, especially North America,