Arum italicum

Arum italicum is a species of flowering herbaceous perennial plant in the family Araceae, also known as Italian arum and Italian lords-and-ladies. It is native to the British Isles and much of the Mediterranean region, the Caucasus, Canary Islands, Madeira and northern Africa. It is also naturalized in Belgium, the Netherlands, Austria, Argentina, North Island New Zealand and scattered locations in North America.

Description

Arum italicum grows high, with equal spread. It blooms in spring with white flowers that turn to showy red fruit.

By relative inflorescence height, Arum species are divided into "cryptic" species, whose inflorescences are borne on a short peduncle amid or below the leaves, and "flag" species, whose inflorescences are above leaf level at the end of long peduncles. A. italicum is a cryptic species.Template:Sfn

In 1778, Lamarck noticed that the inflorescence of this plant produces heat.

A. italicum generally has a chromosome count of 2n = 84, except that a few subspecies (such as subsp. albispathum) have 2n = 56.

Taxonomy

Within the genus, A. italicum belongs to subgenus Arum, section Arum.

Arum italicum may hybridize with Arum maculatum. The status of two subspecies currently included in Arum italicum, subsp. albispathum (Crimea to the Caucasus) and subsp. canariense (Macaronesia), is uncertain and they may represent independent species.

Distribution and habitat

Arum italicum nativity by subspecies is as follows:

• A. italicum subsp. italicum is native to Albania, Algeria, Baleares, Bulgaria, Corse, Cyprus, France, Greece, Iraq, Italy, Kriti, Krym, Morocco, Portugal, Sardegna, Sicilia, Spain, Switzerland, Tunisia, Turkey, Turkey-in-Europe, and Yugoslavia.
• A. italicum subsp. albispathum is native to Krym, North Caucasus, Transcaucasus, and Turkey.
• A. italicum subsp. canariense is native to Azores, Canary Islands, and Madeira.
• A. italicum subsp. neglectum is native to Algeria, France, Great Britain, Morocco, and Spain.

Subspecies italicum has a multi-continental introduced presence, including in northeast Argentina, Austria, Belgium, Germany, Great Britain, Ireland, the Netherlands, north New Zealand, and the U.S. states of Illinois, Maryland, Missouri, New York, and North Carolina.

Invasive species

Arum italicum can be invasive in some areas, particularly in the Pacific Northwest of the United States. It is very difficult to control once established. Herbicides kill the foliage of the plant, but may not affect the tuber. Manual control may spread the plants through the dissemination of soil contaminated with bulb and root fragments.

Uses

In Croatia, its corms were eaten in times of famine.Template:SfnTemplate:SfnTemplate:Sfn

Toxicity

Leaves, fruits and rhizomes contain compounds that make them poisonous. Notably, the plants are rich in oxalates. The ingestion of the tuber may be fatal, as it affects the kidneys, digestive tract, and brain.

Cultivation

It is cultivated as an ornamental plant for traditional and woodland shade gardens. Subspecies italicum (the one normally grown in horticulture) has distinctive pale veins on the leaves, whilst subspecies neglectum (known as late cuckoo pint) has faint pale veins, and the leaves may have dark spots. Nonetheless, intermediates between these two subspecies also occur, and their distinctiveness has been questioned. Some gardeners use this arum to underplant with Hosta, as they produce foliage sequentially: when the Hosta withers away, the arum replaces it in early winter, maintaining ground-cover. Numerous cultivars have been developed for garden use, of which A. italicum subsp. italicum 'Marmoratum' has gained the Royal Horticultural Society's Award of Garden Merit.

Gallery

• Corms
  Corms
• Mature leaves
  Mature leaves
• Spathe
  Spathe
• Maturing fruit
  Maturing fruit
• Ripe fruit
  Ripe fruit
• Botanical illustration
  Botanical illustration
• Leaves of cultivar 'Marmoratum'
  Leaves of cultivar 'Marmoratum'

External links

• Missouri Botanical Garden - Kemper Center for Home Gardening - Arum italicum
• Invasive Plant Atlas Italian arum - Arum italicum