Solidago altissima

Solidago altissima
Conservation status
Secure (NatureServe)
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Asterids
Order:	Asterales
Family:	Asteraceae
Genus:	Solidago
Species:	S. altissima
Binomial name
Solidago altissima L.
Synonyms[1]
Solidago hirsutissima Mill. Solidago lunellii Rydb. Solidago scabra Muhl. ex Willd. Doria gilvocanescens (Rydb.) Lunell, syn of subsp. gilvocanescens Solidago gilvocanescens (Rydb.) Smyth, syn of subsp. gilvocanescens Solidago pruinosa Greene, syn of subsp. gilvocanescens

Solidago altissima, the tall goldenrod^[2] or late goldenrod,^[3] is a North American species of goldenrod widespread across much of Canada, the United States, and northern Mexico.^[3] It is common in much of its range, and fairly tolerant of landscapes which have been disturbed by humans.^[4] It has become naturalized in many parts of the world.^[3][5][6]

Description[]

Solidago altissima is one to two meters (40-80 inches) tall, with fine hairs on the stem. The leaves are located along the stem, not in a rosette near the ground. One plant can produce as many as 1500 small yellow flower heads in a large conical array.^[3]

Solidago altissima is self-incompatible, meaning that the pollen from one plant cannot pollinate the female flower parts of the same plant.^[4]

Classification[]

Solidago altissima has diploid, tetraploid, and hexaploid populations and morphological variations which has generally led to classifying it into two subspecies, which roughly speaking can be identified as being from the eastern and western parts of the continent. At least in the Midwest, it is common to have plants of different ploidy interspersed, with little apparent tendency for one type to dominate even a fairly local geographical area.^[4]

Within Solidago, S. altissima is part of the Solidago canadensis species complex, which is classified in the subsection Triplinervae.^[4] S. altissima has sometimes been classified as part of S. canadensis.^[3]

Subspecies^[1][3][7]

• Solidago altissima subsp. altissima: This is the autonym subspecies. It is in eastern Canada except Newfoundland and Labrador, and it is in the provinces of Saskatchewan and Manitoba.^[8] In the United States, it is east of the Mississippi River except Wisconsin, Illinois, and North Carolina; all U.S. states directly on the west of the Mississippi River; and, Nebraska, Kansas, Oklahoma, Texas, Utah, Arizona, and California.^[8] In Mexico, it is in the north except on the Baja California Peninsula, Sonora, and Sinaloa.^[8] It is in all other states as far south as Oaxaca and Veracruz except Mexico, Morelos, Puebla, Tlaxcala, and Mexico City.^[8] It is native in all of the above states and provinces where it resides.^[8] It is an introduced species in East China, South Central China, Korea, New South Wales, Taiwan, and Transcaucasus.^[8]

• Solidago altissima subsp. gilvocanescens (Rydb.) Semple: This subspecies is in western Canada and Ontario.^[9] In the United States, it is only east of the Mississippi River in Illinois, and is then distributed west through the Great Plains states.^[9] In Mexico, it overlaps subsp. altissima except in the west.^[9]

Defense against herbivory[]

Ducking[]

Ducking has been found to occur in populations of S. altissima as a defense mechanism.^[10] This is a process in which certain individuals within a population will bow until their tops point downward in an effort to hide from egg laying insects.^[10] This bowing is temporary only occurring during the egg laying period of species that use the plant as a host such as Eurosta solidaginis and Rhopalomyia solidaginis.^[10] Insect species inject their eggs into goldenrod buds causing spherical swelling on the plant known as a gall.^[11] Members of the population with this “candy-cane” phenotype experience a lower chance of hosting eggs and having galls formed by these herbivores.^[10]

Individuals that undergo ducking are in the minority with most individuals staying upright through growth and flowering.^[10] This genetic phenomenon of two stem growth phenotypes within one species is a form of dimorphism.^[12] Though ducking provides S. altissima with the benefit of being able to avoid damage from insect oviposition the fact that it occurs in a low amount of individuals in populations suggests that there is a cost to having this trait that could prevent it from becoming the major phenotype.^[12]

Chemical defense[]

S. altissima produce cysteine and serine protease inhibitors as an inducible defense against herbivory.^[13] These protease inhibitors can negatively affect the digestive system of herbivores slowing growth and reproduction making them an effective mean of resistance.^[14] The production of these inhibitors is costly and can vary between populations, possibly being lower in areas that are not subject to as much predation.^[15][13]

References[]