Pinus thunbergii

Pinus thunbergii(syn:Pinus thunbergiana), theblack pine,Japanese black pine,orJapanese pine,is apinetree native to coastal areas of Japan (Kyūshū,ShikokuandHonshū) and South Korea.

Black pine
Pruned black pines in Japanese National Garden, Tokyo
Conservation status
Least Concern(IUCN 3.1)
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Gymnospermae
Division:	Pinophyta
Class:	Pinopsida
Order:	Pinales
Family:	Pinaceae
Genus:	Pinus
Subgenus:	P.subg.Pinus
Section:	P.sect.Pinus
Subsection:	P.subsect.Pinus
Species:	P. thunbergii
Binomial name
Pinus thunbergii Parl.
Synonyms
Pinus thunbergiana

It is calledgomsol(곰솔) inKorean,hēisōng(Hắc tùng) inChinese,andkuromatsu(Hắc tùng) inJapanese.

Description

Black pines can reach the height of 40 metres (130 feet), but rarely achieves this size outside its natural range. The needles are infasciclesof two with a white sheath at the base,7–12 centimetres (2+3⁄4–4+3⁄4inches) long. Female cones are4–7 cm (1+1⁄2–2+3⁄4in) in length, scaled, with small points on the tips of the scales, taking two years to mature. Male cones are1–2 cm (1⁄2–3⁄4in) long borne in clumps of 12–20 on the tips of the spring growth. Thebarkis gray on young trees and small branches, changing to black and plated on larger branches and the trunk; becoming quite thick on older trunks.It is a widely adapted plant with attractive dark green foliage.

Ecology

In North America this tree is subject to widespread mortality by the native American pinewood nematode,Bursaphelenchus xylophilus,spread by means of beetle vectors. Subsequently,blue stain fungusinvades the plant, leading to a rapid decline and death. Thisnematodehas also been introduced to Japan accidentally, leading to the species becoming endangered in its native area.

Uses

Because of its resistance to pollution and salt, it is a popular horticultural tree. In Japan it is widely used as a garden tree, both trained asniwakiand untrained growing as an overstory tree. The trunks and branches are trained from a young age to be elegant and interesting to view. It is one of the classicbonsaisubjects, requiring great patience over many years to train properly.

Second flush of growth

One characteristic of the Japanese black pine that makes it desirable for bonsai, is the possibility of inducing a second flush of new growth and improved ramification in a single growing season. Unlike most pines, which are single flush plants, the Japanese black pine can be induced to produce newbudsat the base of each spring candle by simply cutting the candles at the base as they elongate, a technique called decandling. This technique will result, in a few weeks, in the flush of multiple new buds at the base of the cut candle; each of these new buds will result in turn in new candles and branches.

Spring candles elongating in early summer in a Japanese black pine.

Japanese black pine var. 'Kotobuki' asbonsai.This tree is over 65 years old and priced by its flaky bark and very short needles.

Gallery

• 
  Pinus thunbergiivar.corticatabonsai
• 
  Pinus thunbergianavar.corticatabonsai
• 
  Well trimmed, small inIchikawa, Chiba
• 
  Close up of trunk inEnoshima
• 
  Pinus thunbergiicv. 'Thunderhead'
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  Close up, the bark seems to be made up of countless shiny metal pieces.

Further reading

• Fu, Liguo; Li, Nan; Elias, Thomas S.; Mill, Robert R."Pinus thunbergii".Flora of China.Vol. 4.Retrieved2018-08-16– via eFloras.org,Missouri Botanical Garden,St. Louis, MO &Harvard University Herbaria,Cambridge, MA.

External links

• Conifers Around the World:Pinus thunbergii- Japanese Black Pine