The conifers, division Pinophyta, also known as division Coniferophyta or Coniferae, are one of 13 or 14 division level taxa within the Kingdom Plantae. Pinophytes are gymnosperms. They are cone-bearing seed plants with vascular tissue; all extant conifers are woody plants, the great majority being trees with just a few being shrubs. Typical examples of conifers include cedars, douglas-firs, cypresses, firs, junipers, kauris, larches, pines, redwoods, spruces, and yews. The division contains approximately eight families, 68 genera, and 630 living species. Although the total number of species is relatively small, conifers are of immense ecological importance. They are the dominant plants over huge areas of land, most notably the boreal forests of the northern hemisphere,[1] but also in similar cool climates in mountains further south. While tropical rain forests have more biodiversity and turnover, the immense conifer forests of the world represent the largest terrestrial carbon sink, i.e. where carbon is bound as organic compounds. They are also of immense economic value, primarily for timber and paper production; the wood of conifers is known as softwood.
The earliest conifers in the fossil record date to the late Carboniferous (Pennsylvanian) period, (about 300 million years ago), possibly arising from Cordaites, a seed-bearing plant with cone-like fertile structures. This plant resembled the modern Araucaria. Pinophyta, Cycadophyta, and Gingkophyta all developed at this time. An important adaptation of these gymnosperms was allowing plants to live without being so dependent on water. Other adaptations are pollen (allowing fertilization to occur without water) and the seed, which allows the embryo to be transported and developed elsewhere.
Conifers appear to be one of the taxa that benefitted from the Permo-Triassic extinction event.
The division name Pinophyta conforms to the rules of the ICBN, which state (Article 16.1) that the names of higher taxa in plants (above the rank of family) are either formed from the name of an included family (usually the most common and/or representative), in this case Pinaceae (the pine family), or are descriptive. In the latter case the name for the conifers (at whatever rank is chosen) is Coniferae (Art 16 Ex 2), which is also in widespread use. Older scientific names (no longer allowed) are Coniferophyta and Coniferales.
According to the ICBN it is possible to use a name formed by replacing the termination -aceae in the name of an included family, in this case preferably Pinaceae, by the appropriate termination, in the case of this division -ophyta. Alternatively, "descriptive botanical names" may also be used at any rank above family. Both are allowed.
This means that if the conifers are regarded to be a division they may be called Pinophyta or Coniferae (if regarded as a class they may be called Pinopsida or Coniferae; if regarded as an order they may be called Pinales or Coniferae (but see also Coniferales)).
Commonly the conifers are considered equivalent to the Gymnosperms, particularly in areas with a temperate climate where they may be the only commonly occurring gymnosperms. However, these are two different levels of grouping: conifers are the largest and economically most important component group of the gymnosperms, but nevertheless they comprise only one of the four groups. The division Pinophyta consists of just one class, Pinopsida, which includes both living and fossil taxa. Subdivision of the living conifers into two or more orders has been proposed from time to time. The most commonly seen in the past was a split into two orders, Taxales (Taxaceae only) and Pinales (the rest), but recent research into DNA sequences suggests that this interpretation leaves the Pinales without Taxales as paraphyletic, and the latter order is no longer regarded as distinct. A more accurate subdivision would be to split the class into three orders, Pinales containing only Pinaceae, Araucariales containing Araucariaceae and Podocarpaceae, and Cupressales containing the remaining families (including Taxaceae), but there has not been any significant support for such a split, with the majority of opinion preferring retention of all the families within a single order Pinales, despite their antiquity and diverse morphology.
The conifers are now accepted as comprising six to eight families, with a total of 65-70 genera and 600-630 species (696 accepted names). The seven most distinct families are linked in the box above right and phylogenetic diagram left. In other interpretations, the Cephalotaxaceae may be better included within the Taxaceae, and some authors additionally recognize Phyllocladaceae as distinct from Podocarpaceae (in which it is included here). The family Taxodiaceae is here included in family Cupressaceae, but was widely recognized in the past and can still be found in many field guides.
The conifers are an ancient group, with a fossil record extending back about 300 million years to the Paleozoic in the late Carboniferous period; even many of the modern genera are recognizable from fossils 60-120 million years old. Other classes and orders, now long extinct, also occur as fossils, particularly from the late Paleozoic and Mesozoic eras. Fossil conifers included many diverse forms, the most dramatically distinct from modern conifers being some herbaceous conifers with no woody stems. Major fossil orders of conifers or conifer-like plants include the Cordaitales, Vojnovskyales, Voltziales and perhaps also the Czekanowskiales (possibly more closely related to the Ginkgophyta).
All living conifers are woody plants, and most are trees, the majority having monopodial growth form (a single, straight trunk with side branches) with strong apical dominance. Many conifers have distinctly scented resin, secreted to protect the tree against insect infestation and fungal infection of wounds. Fossilized resin hardens into amber. The size of mature conifers varies from less than one meter, to over 100 meters The world's tallest, largest, thickest and oldest living things are all conifers. The tallest is a Coast Redwood (Sequoia sempervirens), with a height of 115.55 meters. The largest is a Giant Sequoia (Sequoiadendron giganteum), with a volume 1486.9 cubic meters . The thickest, or tree with the greatest trunk diameter, is a Montezuma Cypress (Taxodium mucronatum), 11.42 meters in diameter. The oldest is a Great Basin Bristlecone Pine (Pinus longaeva), 4,700 years old.
Since most conifers are evergreens, the leaves of many conifers are long, thin and have a needle-like appearance, but others, including most of the Cupressaceae and some of the Podocarpaceae, have flat, triangular scale-like leaves. Some, notably Agathis in Araucariaceae and Nageia in Podocarpaceae, have broad, flat strap-shaped leaves. Others such as Araucaria columnaris have leaves that are awl-shaped. In the majority of conifers, the leaves are arranged spirally, exceptions being most of Cupressaceae and one genus in Podocarpaceae, where they are arranged in decussate opposite pairs or whorls of 3 (-4). In many species with spirally arranged leaves, the leaf bases are twisted to present the leaves in a very flat plane for maximum light capture (see e.g. photo of Grand Fir Abies grandis). Leaf size varies from 2 mm in many scale-leaved species, up to 400 mm long in the needles of some pines (e.g. Apache Pine Pinus engelmannii). The stomata are in lines or patches on the leaves, and can be closed when it is very dry or cold. The leaves are often dark green in colour which may help absorb a maximum of energy from weak sunshine at high latitudes or under forest canopy shade. Conifers from hotter areas with high sunlight levels (e.g. Turkish Pine Pinus brutia) often have yellower-green leaves, while others (e.g. Blue Spruce Picea pungens) have a very strong glaucous wax bloom to reflect ultraviolet light. In the great majority of genera the leaves are evergreen, usually remaining on the plant for several (2-40) years before falling, but five genera (Larix, Pseudolarix, Glyptostrobus, Metasequoia and Taxodium) are deciduous, shedding the leaves in autumn and leafless through the winter. The seedlings of many conifers, including most of the Cupressaceae, and Pinus in Pinaceae, have a distinct juvenile foliage period where the leaves are different, often markedly so, from the typical adult leaves.
Most conifers are monoecious, but some are subdioecious or dioecious; all are wind-pollinated. Conifer seeds develop inside a protective cone called a strobilus. The cones take from four months to three years to reach maturity, and vary in size from 2 mm to 600 mm long.
In Pinaceae, Araucariaceae, Sciadopityaceae and most Cupressaceae, the cones are woody, and when mature the scales usually spread open allowing the seeds to fall out and be dispersed by the wind. In some (e.g. firs and cedars), the cones disintegrate to release the seeds, and in others (e.g. the pines that produce pine nuts) the nut-like seeds are dispersed by birds (mainly nutcrackers and jays) which break up the specially adapted softer cones. Ripe cones may remain on the plant for a varied amount of time before falling to the ground; in some fire-adapted pines, the seeds may be stored in closed cones for up to 60-80 years, being released only when a fire kills the parent tree.
In the families Podocarpaceae, Cephalotaxaceae, Taxaceae, and one Cupressaceae genus (Juniperus), the scales are soft, fleshy, sweet and brightly colored, and are eaten by fruit-eating birds, which then pass the seeds in their droppings. These fleshy scales are (except in Juniperus) known as arils. In some of these conifers (e.g. most Podocarpaceae), the cone consists of several fused scales, while in others (e.g. Taxaceae), the cone is reduced to just one seed scale or (e.g. Cephalotaxaceae) the several scales of a cone develop into individual arils, giving the appearance of a cluster of berries.
The male cones have structures called microsporangia which produce yellowish pollen through meiosis. Pollen is released and carried by the wind to female cones. Pollen grains from living pinophyte species produce pollen tubes, much like those of angiosperms. When a pollen grain lands near a female gametophyte, it undergoes fertilization of the female gametophyte. Alternatively, the gymnosperm male gametophytes are carried by wind to a female cone and are drawn into a tiny opening on the ovule called the micropyle. It is within the ovule that germination occurs. From here, a pollen tube seeks out the female gametophyte and if successful, fertilization will occur. In both cases, the resulting zygote develops into an embryo, which along with its surrounding integument, becomes a seed. Eventually the seed may fall to the ground and, if conditions permit, grows into a new plant.
In forestry, the terminology of flowering plants has commonly though inaccurately been applied to cone-bearing trees as well. The male cone and unfertilized female cone are called "male flower" and "female flower", respectively. After fertilization, the female cone is termed "fruit", which undergoes "ripening" (maturation).
Life cycle
To fertilize the ovum, the male cone releases pollen that is carried on the wind to the female cone. (Male and female cones can be found on the same plant)
The pollen fertilizes the female gamete (located in the female cone).*
A fertilized female gamete (called a zygote) develops into an embryo.
Along with integument cells surrounding the embryo, a seed develops containing the embryo. This is an evolutionary characteristic of the gymnosperms.
Mature seed drops out of cone onto the ground.
Seed germinates and seedling grows into a mature plant.
When the plant is mature, the adult plant produces cones and the cycle continues.
Wilding conifers, also known as wilding pines, are invasive tree species in the high country of New Zealand.
In the South Island, they threaten 210,000 hectares of public land administered by the Department of Conservation and are also present on privately owned land and other public land such as roadsides. The wilding conifers are considered to be a threat to biodiversity, farm productivity and to landscape values. Since they often invade tussock grasslands, which are characterised by low lying vegetation that is considered to a natural environment, the tall trees become a prominent and unwanted feature.
Without any control measures wilding conifers will spread over an increasing area with economic and environmental consequences. As well as volunteers organised by environmental groups, regional councils and the Department of Conservation invest in wild conifer removal.
A South Island Wilding Conifer Management Group was formed in 2006 and obtained funding from the Ministry of Agriculture and Forestry Sustainable Farming Fund.
Mechanical removal by hand pulling seedlings, and the use of brush cutters and chainsaws are common control methods. Spray trials are also being carried out. In 2004 a spraying operation by the Department of Conservation at Mid Dome in the Southland Region caused spray drift onto surrounding areas including the towns of Athol and Kingston.
Pest management is administered by regional councils. There are sixteen different regions in New Zealand and wilding confers only occur in a few of these regions, predominately in the South Island. The Department of Conservation manages wilding conifers on public land under its jurisdiction
In its current Pest Management Strategy the Canterbury Regional Council has the objective of eradicating all self sown wilding conifers in ecologically sensitive areas in its jurisdiction. To do this a range of measures are used, including carrying out wilding conifer control operations, encouraging reporting of the presence of wilding conifers, encouraging the removal of seed sources and advocating changes to the district plans of the territorial authorities to prevent or control the planting of inappropriate conifers.
Pinus contorta infests the south Marlborough area and is classed as a "Containment Control Pest", which are pests that are managed to prevent spreading to new areas. Other wilding species exist in Marlborough but Lodgepole Pine is the focus for pest management
Hawke's Bay (Heretaunga) is a region of New Zealand. Hawke's Bay is recognised on the world stage for its award-winning wines. The regional council sits in both the cities of Napier and Hastings.
The region is situated on the east coast of the North Island. The region bears the former name of what is now Hawke Bay, a large semi-circular bay which extends for 100 kilometres from northeast to southwest from Mahia Peninsula to Cape Kidnappers.
The Hawke's Bay region includes the hilly coastal land around the northern and central bay, the floodplains of the Wairoa River in the north, the wide fertile Heretaunga Plains around Hastings in the south, and a hilly interior stretching up into the Kaweka and Ruahine Ranges.
The region's boundaries vary somewhat from the former provincial boundaries of Hawke's Bay, and some towns in the Manawatu-Wanganui Region to the southwest, such as Dannevirke and Woodville have a historical association with Hawke's Bay.
The region consists of Wairoa District, Hastings District, Napier City, and Central Hawke's Bay District, as well as the town of Taharua in Taupo District and the town of Ngamatea in Rangitikei District.
One trivial fact is that the region has a hill with the longest place name in New Zealand, and the longest in the world according to the 2009 Guinness Book of
The sub-national GDP of the the Hawke's Bay region was estimated at US$4.3 billion in 2003, 3% of New Zealand's national GDP
Hawkes Bay provence was founded in 1858 as a Province of New Zealand, after being separated from the Wellington Province following a meeting in Napier in February 1858. The Province was abolished in 1876 along with all other provinces in New Zealand. It was replaced with a Provincial District.
On February 3, 1931, Napier and Hastings were devastated following New Zealand's worst natural disaster. An earthquake measuring 7.9 on the Richter Scale killed 256 people. Napier began re-building and now the city is world famous for its Art Deco buildings and celebrates its heritage each February with the Art Deco Weekend. An exhibition on the earthquake, its causes and impact, at the Hawke's Bay Museum and Art Gallery is a popular destination for visitors.
The region's population is 153,400 from the June 2009 estimate. Of these, 57,200 lived in Napier City and 74,300 lived in Hastings. The main urban areas are Napier and Hastings. Smaller communities include Wairoa, Taradale, Havelock North, Tikokino, Waipawa, Waipukurau, and Takapau. The region has a significant Māori population (24% of the total population at the 2006 census). A major local Māori tribe is Ngāti Kahungunu.
There are over two thousand Muslim residents in the region, mostly new immigrants and some local converts to Islam.
Hawke's Bay's long, hot summers and cool winters offer the best weather for growing grapes. The climate is dry and temperate. Hawke's Bay is renowned for its horticulture with large orchards and vineyards on the plains. In the hilly parts of the region sheep and cattle farming predominates, with forestry blocks in the roughest areas.
The region is served by a variety of radio stations with Classic Hits 89.5 Bay City Radio, and Newstalk ZB being the most popular local stations. Hawke's Bay also has its own TV station, TVHB, which provides a mix of news and information programmes hosted by local personalities.
Hawke's Bay produces some of New Zealand's finest wines and once a year Harvest Hawke's Bay celebrates the fact by offering a three day wine and food festival. This event attracts many thousands.
Napier is home to the annual Mission Concert held early each year. The event held at the Mission Estate Winery in Taradale has attracted big names over the year's including Kenny Rogers, Shirley Bassey, Rod Stewart, The B-52's, Belinda Carlisle, Ray Charles, and Eric Clapton. Each concert is attended by around 25,000 people. The 2009 concert attraction was to be Lionel Richie, but the concert was cancelled because of rain.
Hawke's Bay has a useful and innovative approach to community-wide care of diabetes mellitus featuring shared records held in a web-based computer system
Missionaries in the mid 19th century first planted vines high and Hawkes Bay and it is now becoming an important place for full bodied red wines. As of January 2010, there is an estimated 74 wineries located across Hawkes Bay.
Inappropriate pesticide application can lead to off-target contamination due to spray drift and "run-off" from plants, causing contamination of the bystanders, the soil, water courses and other environmental pollution.
With placement (localised) spraying of broad spectrum pesticides, wind drift must be minimised, and considerable efforts have been made recently to quantify and control spray drift from hydraulic nozzles. On the other hand, wind drift is also an efficient mechanism for moving droplets of an appropriate size range to their targets over a wide area with ultra-low volume (ULV) spraying. Himel (1974) made a distinction between exo-drift (the transfer of spray out of the target area) and endo-drift, where the active ingredient (AI) in droplets falls into the target area, but does not reach the biological target. Endo-drift is volumetrically more significant and may therefore cause greater ecological contamination (e.g. where chemical pesticides pollute ground water).
Although there has been much public concern and research into spray drift, several studies have concluded that point source pollution (allowing pesticides to enter water courses/groundwater following spillage of concentrate or after washing equipment) can cause the greatest harm to the environment.
Wisteria (also spelled Wistaria) is a genus of flowering plants in the pea family, Fabaceae. It contains about ten species of woody climbing vines native to the eastern United States and the East Asian states of China, Korea, and Japan. Aquarists refer to the species Hygrophila difformis, in the family Acanthaceae, as Water Wisteria.
Wisteria vines climb by twining their stems either clockwise or counter-clockwise round any available support. They can climb as high as 20 m above ground and spread out 10 m laterally. The world's largest known Wisteria vine is located in Sierra Madre, California, measuring more than 1 acre (0.40 ha) in size and weighing 250 tons.
The leaves are alternate, 15 to 35 cm long, pinnate, with 9 to 19 leaflets. The flowers are produced in pendulous racemes 10 to 80 cm long, similar to those of the genus Laburnum, but are purple, violet, pink or white, not yellow. Flowering is in the spring (just before or as the leaves open) in some Asian species, and in mid to late summer in the American species and W. japonica. The flowers of some species are fragrant, most notably Chinese Wisteria. The seeds are produced in pods similar to those of Laburnum, and, like that genus, are poisonous.
There are two noted attributions for the name Wisteria. One, that the botanist Thomas Nuttall named the genus Wisteria in honour of Dr. Caspar Wistar (1761 - 1818) — some call it Wistaria but the misspelling is conserved under the International Code of Botanical Nomenclature. The other, that the genus was named after Charles Jones Wister, Sr., of Grumblethorpe, the grandson of merchant and wine importer John Wister. Daniel Wister, Charles's father, joined with Samuel Miles and Robert Morris to underwrite the voyage of the American commercial vessel Empress of China.[citation needed] On board the ship was the vine that would later bear the Wister name.
Wisteria species are used as food plants by the larvae of some Lepidoptera species including brown-tail. It is also an extremely popular ornament in China and Japan.
Wisteria, especially Wisteria sinensis, is very hardy and fast-growing. It is considered an invasive species in certain areas. It can grow in fairly poor-quality soils, but prefers fertile, moist, well-drained ones. It thrives in full sun to partial shade.
Wisteria can be propagated via hardwood cutting, softwood cuttings, or seed. However, seeded specimens can take decades to bloom; for that reason, gardeners usually grow plants that have been started from rooted cuttings or grafted cultivars known to flower well. Another reason for failure to bloom can be excessive fertilizer (particularly nitrogen). Wisteria has nitrogen fixing capability (provided by Rhizobia bacteria in root nodules), and thus mature plants may benefit from added potassium and phosphate, but not nitrogen. Finally, wisteria can be reluctant to bloom because it has not reached maturity. Maturation may require only a few years, as in Kentucky Wisteria, or nearly twenty, as in Chinese Wisteria. Maturation can be forced by physically abusing the main trunk, root pruning, or drought stress.
Wisteria can grow into a mound when unsupported, but is at its best when allowed to clamber up a tree, pergola, wall, or other supporting structure. Whatever the case, the support must be very sturdy, because old wisteria can grow into immensely strong and heavy wrist-thick trunks and stems. These will certainly rend latticework, crush thin wooden posts, and can even strangle large trees. Wisteria allowed to grow on houses can cause damage to gutters, downspouts, and similar structures. Its pendulous racemes are best viewed from below.
Wisteria flowers develop in buds near the base of the previous year's growth, so pruning back side shoots to the basal few buds in early spring can enhance the visibility of the flowers. If it is desired to control the size of the plant, the side shoots can be shortened to between 20 and 40 cm long in mid summer, and back to 10 to 20 cm in the fall. The flowers of some varieties are edible, and can even be used to make wine. Others are said to be toxic. Careful identification by an expert is strongly recommended before consuming this or any wild plant.
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