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34-451: See List of Pinus species for complete taxonomy to species level. See list of pines by region for list of species by geographic distribution . A pine is any conifer tree or shrub in the genus Pinus ( / ˈ p aɪ n ə s / ) of the family Pinaceae . Pinus is the sole genus in the subfamily Pinoideae . World Flora Online accepts 187 species names of pines as current, with additional synonyms, making it

68-553: A larger amount of resin than the haploxylon pines. The current division into two subgenera ( Pinus and Strobus ) is supported with rigorous genetic evidence. Several features are used to distinguish the subgenera, sections, and subsections of pines: the number of leaves (needles) per fascicle , whether the fascicle sheaths are deciduous or persistent , the number of fibrovascular bundles per needle (2 in Pinus or 1 in Strobus ),

102-564: A means to evaluate soil fertility and vigour of the trees. The bark of most pines is thick and scaly, but some species have thin, flaky bark. The branches are produced in "pseudo whorls", actually a very tight spiral but appearing like a ring of branches arising from the same point. Many pines are uninodal, producing just one such whorl of branches each year, from buds at the tip of the year's new shoot , but others are multinodal, producing two or more whorls of branches per year. Pines have four types of leaf : Pines are monoecious , having

136-478: A single plant, reducing the effects of inbreeding . It often accompanies dioecy – the presence of male and female reproductive structures on separate plants. Anemophily is adaptively beneficial because it promotes outcrossing and thus the avoidance of inbreeding depression that can occur due to the expression of recessive deleterious mutations in inbred progeny plants. Almost all pollens that are allergens are from anemophilous species. People allergic to

170-450: Is named after P. pinaster . Section Trifoliae (American hard pines), despite its name (which means "three-leaved"), has two to five needles per fascicle, or rarely eight. The cones of most species open at maturity, but a few are serotinous . All but two American hard pines belong to this section. Phylogenetic analysis supports ancient divergences within this section, with subsections Australes and Ponderosae having diverged during

204-908: Is native to Central America , Mexico , the western United States , and southwestern Canada , although its former range was possibly much wider as evidenced by upper Miocene fossils belonging to this subsection found in Japan Subgenus Strobus includes the white and soft pines. Pines in this subgenus have one to five needles per fascicle and one fibrovascular bundle per needle, and the fascicle sheaths are deciduous , except in P. nelsonii , where they are persistent. Cone scales are thinner and more flexible than those of subgenus Pinus , except in some species like P. maximartinezii , and cones usually open soon after they mature. Section Parrya has one to five needles per fascicle. The seeds either have articulate (jointed) wings or no wings at all. In all species except for P. nelsonii ,

238-656: Is native to East Asia. It has three or five needles per fascicle. Subsection Krempfianae is currently native to Vietnam, with a fossil record extending into the Oligocene. It has two needles per fascicle, and they are atypically flattened. The cone scales are thick and have no prickles. Until 2021, the subsection was considered monotypic, when an Oligocene fossil species was described from Yunnan Province, China. Subsection Strobus has five needles per fascicle and thin cone scales with no prickles. Needles tend to be flexible and soft with slightly lighter side underneath. It

272-465: Is native to North and Central America, Europe, and Asia. Species which are not placed in a subgenus at this time. Anemophily Features of the wind-pollination syndrome include a lack of scent production, a lack of showy floral parts (resulting in small, inconspicuous flowers), reduced production of nectar , and the production of enormous numbers of pollen grains. This distinguishes them from entomophilous and zoophilous species (whose pollen

306-646: Is native to northeastern Mexico. It consists of the single species with persistent fascicle sheaths. Section Quinquefoliae (white pines), as its name (which means "five-leaved") suggests, has five needles per fascicle except for P. krempfii , which has two, and P. gerardiana and P. bungeana , which have three. All species have cones with thin or thick scales that open at maturity or do not open at all; none are serotinous. Species in this section are found in Eurasia and North America, and one species, P. chiapensis reaches Guatemala. Subsection Gerardianae

340-405: Is no longer used. Subsection Ponderosae Subsection Contortae Subsection Australes Subsection Pinus Subsection Pinaster Subsection Gerardianae Subsection Krempfianae Subsection Strobus Subsection Nelsonianae Subsection Balfourianae Subsection Cembroides The species of subgenus Ducampopinus were regarded as intermediate between the other two subgenera. In

374-448: Is now restricted to fir ( Abies ) and Douglas-fir ( Pseudotsuga ). Pines are gymnosperms . The genus is divided into two subgenera based on the number of fibrovascular bundles in the needle. The subgenera can be distinguished by cone, seed, and leaf characters: Phylogenetic evidence indicates that both subgenera have a very ancient divergence from one another. Each subgenus is further divided into sections and subsections. Many of

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408-415: Is often found in honey made during the ragweed floral bloom. Other flowers that are generally anemophilous are observed to be actively worked by bees, with solitary bees often visiting grass flowers, and the larger honeybees and bumblebees frequently gathering pollen from corn tassels and other grains. Anemophily is an adaptation that helps to separate the male and female reproductive systems of

442-491: Is one of the most extensively used types of timber. There are currently 818 named cultivars (or trinomials ) recognized by the ACS. It is a well-known type of Christmas tree . Pine trees are evergreen , coniferous resinous trees (or, rarely, shrubs ) growing 3–80 metres (10–260 feet) tall, with the majority of species reaching 15–45 m (50–150 ft) tall. The smallest are Siberian dwarf pine and Potosi pinyon , and

476-501: Is spread by insects and vertebrates respectively). Anemophilous pollen grains are smooth, light, and non-sticky, so that they can be transported by air currents. Wind-pollinating plants have no predisposition to attract pollinating organisms. They freely expel a myriad of these pollen grains, and only a small percentage of them ends up captured by the female floral structures on wind-pollinated plants. They are typically 20–60 micrometres (0.0008–0.0024 in) in diameter, although

510-650: Is the largest genus of the Pinaceae , the pine family, which first appeared in the Jurassic period. Based on recent Transcriptome analysis, Pinus is most closely related to the genus Cathaya , which in turn is closely related to spruces . These genera, with firs and larches , form the pinoid clade of the Pinaceae. Pines first appeared during the Early Cretaceous, with the oldest verified fossil of

544-675: The Mediterranean , except for P. resinosa in northeastern North America and P. tropicalis in western Cuba . Subsection Incertae sedis All but two species ( P. resinosa and P. tropicalis ) in Subsection Pinus are native to Eurasia. Subsection Pinaster contains species native to the Mediterranean, as well as P. roxburghii from the Himalayas . The scales of its cones lack spines. It

578-694: The White Mountains of California. An older tree, now cut down, was dated at 4,900 years old. It was discovered in a grove beneath Wheeler Peak and it is now known as " Prometheus " after the Greek immortal . The spiral growth of branches, needles, and cones scales are arranged in Fibonacci number ratios. The new spring shoots are sometimes called "candles"; they are covered in brown or whitish bud scales and point upward at first, then later turn green and spread outward. These "candles" offer foresters

612-706: The pines , is a genus of approximately 111 extant tree and shrub species. The genus is currently split into two subgenera : subgenus Pinus ( hard pines ), and subgenus Strobus ( soft pines ). Each of the subgenera have been further divided into sections based on chloroplast DNA sequencing and whole plastid genomic analysis. Older classifications split the genus into three subgenera – subgenus Pinus , subgenus Strobus , and subgenus Ducampopinus ( pinyon , bristlecone and lacebark pines) – based on cone, seed and leaf characteristics. DNA phylogeny has shown that species formerly in subgenus Ducampopinus are members of subgenus Strobus , so Ducampopinus

646-664: The Indo-European base *pīt- ‘resin’ (source of English pituitary ). Before the 19th century, pines were often referred to as firs (from Old Norse fura , by way of Middle English firre ). In some European languages, Germanic cognates of the Old Norse name are still in use for pines — in Danish fyr , in Norwegian fura/fure/furu , Swedish fura/furu , Dutch vuren , and German Föhre — but in modern English, fir

680-431: The fascicle sheaths curl back to form a rosette before falling away. The cones have thick scales and release the seeds at maturity. This section is native to the southwestern United States and Mexico. Subsection Balfourianae (bristlecone pines) is native to southwest United States . Subsection Cembroides (pinyons or piñons) is native to Mexico and the southwestern United States . Subsection Nelsonianae

714-560: The genus being Pinus yorkshirensis from the Hauterivian - Barremian boundary (~130-125 million years ago) from the Speeton Clay , England. The evolutionary history of the genus Pinus has been complicated by hybridization . Pines are prone to inter-specific breeding. Wind pollination, long life spans, overlapping generations, large population size, and weak reproductive isolation make breeding across species more likely. As

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748-692: The largest family among the conifers. The American Conifer Society (ACS) and the Royal Horticultural Society accept 121 species. The highest species diversity of pines is found in Mexico. Pines are widely distributed in the Northern Hemisphere ; they occupy large areas of boreal forest , but are found in many habitats, including the Mediterranean Basin . The timber from pine trees is called "pine"; it

782-505: The male and female cones on the same tree. The male cones are small, typically 1–5 cm long, and only present for a short period (usually in spring, though autumn in a few pines), falling as soon as they have shed their pollen . The female cones take 1.5–3 years (depending on species) to mature after pollination , with actual fertilization delayed one year. At maturity the female cones are 3–60 cm long. Each cone has numerous spirally arranged scales, with two seeds on each fertile scale;

816-470: The mid- Cretaceous . Subsection Australes is native to North and Central America and islands in the Caribbean . The closed-cone (serotinous) species of California and Baja California, P. attenuata , P. muricata , and P. radiata , are sometimes placed in a separate subsection, Attenuatae . Subsection Contortae is native to North America and Mexico. Subsection Ponderosae

850-781: The modern classification, they are placed into subgenus Strobus , yet they did not fit entirely well in either so they were classified in a third subgenus. In 1888 the Californian botanist John Gill Lemmon placed them in subgenus Pinus . In general, this classification emphasized cone, cone scale, seed, and leaf fascicle and sheath morphology, and species in each subsection were usually recognizable by their general appearance. Pines with one fibrovascular bundle per leaf, (the former subgenera Strobus and Ducampopinus ) were known as haploxylon pines , while pines with two fibrovascular bundles per leaf, (subgenus Pinus ) were called diploxylon pines . Diploxylon pines tend to have harder timber and

884-778: The pines have diversified, gene transfer between different species has created a complex history of genetic relatedness. P. nelsonii P. aristata P. balfouriana P. longaeva P. pinceana P. maximartinezii P. rzedowskii P. quadrifolia P. monophylla P. culminicola P. discolor P. remota P. edulis P. cembroides P. bungeana P. squamata P. gerardiana P. krempfii P. peuce P. lambertiana P. strobus P. chiapensis P. monticola P. flexilis P. strobiformis P. ayacahuite P. albicaulis P. koraiensis P. sibirica P. cembra P. parviflora P. wallichiana List of Pinus species Pinus ,

918-809: The pollen grains of Pinus species can be much larger and much less dense. Anemophilous plants possess lengthy, well-exposed stamens to catch and distribute pollen. These stamens are exposed to wind currents and also have large, feathery stigma to easily trap airborne pollen grains. Pollen from anemophilous plants tends to be smaller and lighter than pollen from entomophilous ones, with very low nutritional value to insects due to their low protein content. However, insects sometimes gather pollen from staminate anemophilous flowers at times when higher- protein pollens from entomophilous flowers are scarce. Anemophilous pollens may also be inadvertently captured by bees ' electrostatic field. This may explain why, though bees are not observed to visit ragweed flowers, its pollen

952-485: The pollen produced by anemophilous plants often have symptoms of hay fever. Grasses ( Poaceae ) are the most important producers of aeroallergens in most temperate regions, with lowland or meadow species producing more pollen than upland or moorland species. In Morocco, it was found that asthma caused by pollen from Poaceae accounted for 10% of the clinical respiratory diseases that patients faced. The nature of how species of Poaceae grasses flower results in an increase in

986-429: The position of the resin ducts in the needles (internal or external), the presence or shape of the seed wings (absent, rudimentary, articulate, and adnate), and the position of the umbo (dorsal or terminal) and presence of a prickle on the scales of the seed cones . Both subgenera are thought to have a very ancient divergence from one another, having diverged during the late Jurassic . Subgenus Pinus includes

1020-453: The scales at the base and tip of the cone are small and sterile, without seeds. The seeds are mostly small and winged, and are anemophilous (wind-dispersed), but some are larger and have only a vestigial wing, and are bird -dispersed. Female cones are woody and sometimes armed to protect developing seeds from foragers. At maturity, the cones usually open to release the seeds. In some of the bird-dispersed species, for example whitebark pine ,

1054-469: The seeds are only released by the bird breaking the cones open. In others, the seeds are stored in closed cones for many years until an environmental cue triggers the cones to open, releasing the seeds. This is called serotiny . The most common form of serotiny is pyriscence, in which a resin binds the cones shut until melted by a forest fire, for example in P. rigida . The modern English name "pine" derives from Latin pinus , which some have traced to

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1088-421: The smaller groups of Pinus are composed of closely related species with recent divergence and history of hybridization. This results in low morphological and genetic differences. This, coupled with low sampling and underdeveloped genetic techniques, has made taxonomy difficult to determine. Recent research using large genetic datasets has clarified these relationships into the groupings we recognize today. Pinus

1122-552: The tallest is an 83.45 m (273.8 ft) tall sugar pine located in Yosemite National Park . Pines are long lived and typically reach ages of 100–1,000 years, some even more. The longest-lived is the Great Basin bristlecone pine ( P. longaeva ). One individual of this species, dubbed " Methuselah ", is one of the world's oldest living organisms at around 4,800 years old. This tree can be found in

1156-583: The yellow and hard pines. Pines in this subgenus have one to five needles per fascicle and two fibrovascular bundles per needle, and the fascicle sheaths are persistent , except in P. leiophylla and P. lumholtzii . Cone scales are thicker and more rigid than those of subgenus Strobus , and cones either open soon after they mature or are serotinous . Section Pinus has two or three needles per fascicle. Cones of all species have thick scales, and all except those of P. pinea open at maturity. Species in this section are native to Europe , Asia , and

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