In botany, a fascicle is a bundle of leaves or flowers growing crowded together; alternatively the term might refer to the vascular tissues that supply such an organ with nutrients. [1] However, vascular tissues may occur in fascicles even when the organs they supply are not fascicled.
The term fascicle and its derived terms such as fasciculation are from the Latin fasciculus, the diminutive of fascis, a bundle. [2] Accordingly, such words occur in many forms and contexts wherever they are convenient for descriptive purposes. A fascicle may be leaves or flowers on a short shoot where the nodes of a shoot are crowded without clear internodes, such as in species of Pinus or Rhigozum . However, bundled fibres, nerves or bristles as in tissues or the glochid fascicles of Opuntia may have little or nothing to do with branch morphology.
Leaf fascicles are present in all pines, and the number of adult leaves (needles) per fascicle is an important character for identification of pine species and genera. Most species have fascicles of 2 to 5 needles; only occasional species typically have as few as one or as many as six leaves to the fascicle.
Variation is high between species, low within them. For example, Pinus flexilis (limber pine), has fascicles of 5 needles. This pine is a member of the white pine group, Pinus subgenus Strobus , section Strobus . In all members of the group the fascicles nearly all have five needles and the sheath at the base of the fascicle is deciduous.
The fascicle sheath is another character that is important for identification. Among North American pines the sheath is persistent in all so-called hard pines and deciduous in all so-called soft pines. [3] Thus, the fascicle sheath and number of needles can be used to identify valuable timber pines in all seasons and many years before they are mature enough to produce cones. These two characters readily distinguish the major groups of pines (see Pinus classification).
Pinus durangensis (Durango pine) has fascicles of 6 needles, rarely 7, and is the only species in Pinus with so many needles per fascicle. At the other extreme, Pinus monophylla has fascicles of one needle, rarely two. This is the only species of pine with just one needle per fascicle, and this rare and easily observed character is reflected in the specific epithet monophylla and in the common name single-leaf pinyon. Although it might strike non-botanists as illogical to apply the term "fascicle" to a stem bearing a single leaf, the justification is that the structure of the stem is consistent with other pine fascicles, which justifies generalising the term to embrace single-needle fascicles as well.
Fascicles do occur in some flowering plants, though not as frequently as in many conifers. Consequently, when fascicles are present the specific epithet often refers to them.
Examples include Prunus fasciculata and Adenostoma fasciculatum . Species with flowers in fascicles include Aechmea biflora and Melicytus ramiflorus , several species of Malva , and the entire genus Flueggea . Some species of the family Alseuosmiaceae have flowers in fascicles.
In the Bignoniaceae in the genus Rhigozum flowers are borne in fascicles from cushion-like, dwarf branchlets in the axils of leaves, and several species also bear leaves in fascicles on similar or shared branchlets. [4]
Both leaf and flower fascicles occur among Angiospermae, often as adaptations facilitating pollination, such as in many Lamiaceae, of which some Lavandula are typical. Other plant fascicles are adaptations to achieve greater compactness for defensive reasons. For example, in Opuntia cacti, spines are produced in fascicles bearing a few long spines and many short spiny bristles (or glochids).
Sphagnum species bear branches in fascicles.
A pine is any conifer tree or shrub in the genus Pinus of the family Pinaceae. Pinus is the sole genus in the subfamily Pinoideae. World Flora Online, created by the Royal Botanic Gardens, Kew and Missouri Botanical Garden, accepts 187 species names of pines as current, together with more synonyms. The American Conifer Society (ACS) and the Royal Horticultural Society accept 121 species. Pines are commonly found in the Northern Hemisphere. Pine may also refer to the lumber derived from pine trees; it is one of the more extensively used types of lumber. The pine family is the largest conifer family and there are currently 818 named cultivars recognized by the ACS.
In botany, an evergreen is a plant which has foliage that remains green and functional through more than one growing season. This contrasts with deciduous plants, which completely lose their foliage during the winter or dry season.
Pinus albicaulis, known by the common names whitebark pine, white bark pine, white pine, pitch pine, scrub pine, and creeping pine, is a conifer tree native to the mountains of the western United States and Canada, specifically subalpine areas of the Sierra Nevada, Cascade Range, Pacific Coast Ranges, and Rocky Mountains. It shares the common name "creeping pine" with several other plants.
Western white pine, also called silver pine and California mountain pine, is a species of pine in the family Pinaceae. It occurs in mountain ranges of northwestern North America and is the state tree of Idaho.
Pinus peuce is a species of pine native to the mountains of North Macedonia, Bulgaria, Albania, Montenegro, Kosovo, the extreme southwest of Serbia, and the extreme north of Greece, growing typically at (600-) 1,000-2,200 (-2,300) m altitude. It often reaches the alpine tree line in this area. The mature size is up to 35–40 m height, and 1.5 m trunk diameter. However, the height of the tree diminishes strongly near the upper tree line and may even obtain shrub sizes.
Pinus flexilis, the limber pine, is a species of pine tree-the family Pinaceae that occurs in the mountains of the Western United States, Mexico, and Canada. It is also called Rocky Mountain white pine.
Pinus strobiformis, commonly known as southwestern white pine, Mexican white pine or Chihuahua white pine, is a medium-sized white pine tree whose native habitat is in southwestern United States and Mexico. It is typically a high-elevation pine growing mixed with other conifers.
Pinus strobus, commonly called the eastern white pine, northern white pine, white pine, Weymouth pine (British), and soft pine is a large pine native to eastern North America. It occurs from Newfoundland, Canada, west through the Great Lakes region to southeastern Manitoba and Minnesota, United States, and south along the Appalachian Mountains and upper Piedmont to northernmost Georgia and perhaps very rarely in some of the higher elevations in northeastern Alabama. It is considered rare in Indiana.
Pinus virginiana, the Virginia pine, scrub pine, Jersey pine, Possum pine, is a medium-sized tree, often found on poorer soils from Long Island in southern New York south through the Appalachian Mountains to western Tennessee and Alabama. The usual size range for this pine is 9–18 m, but can grow larger under optimum conditions. The trunk can be as large as 20 inches diameter. This tree prefers well-drained loam or clay, but will also grow on very poor, sandy soil, where it remains small and stunted. The typical life span is 65 to 90 years.
Pinus densiflora, also called the Japanese red pine, the Japanese pine, or Korean red pine, is a species of pine tree native to East Asia. In China it is known as 赤松.
Pinus cembra, also known as Swiss pine, Swiss stone pine or Arolla pine or Austrian stone pine or just stone pine, is a species of pine tree in the subgenus Strobus.
Pinus sibirica, or Siberian pine, in the family Pinaceae is a species of pine tree that occurs in Siberia from 58°E in the Ural Mountains east to 126°E in the Stanovoy Range in southern Sakha Republic, and from Igarka at 68°N in the lower Yenisei valley, south to 45°N in central Mongolia.
Pinus edulis, the Colorado pinyon, two-needle piñon, pinyon pine, or simply piñon, is a pine in the pinyon pine group whose ancestor was a member of the Madro-Tertiary Geoflora and is native to the United States.
Pinus ayacahuite, also called ayacahuite pine and Mexican white pine, is a species of pine native to the mountains of southern Mexico and western Central America, in the Sierra Madre del Sur mountains and the eastern end of the Eje Volcánico Transversal, between 14° and 21°N latitude in the Mexican states of Guerrero, Oaxaca, Puebla, Veracruz and Chiapas, and in Guatemala, El Salvador and Honduras. It grows on relatively moist areas with summer rainfalls, however specimens from its eastern and southern distribution live under really wet conditions; it needs full sun and well drained soils. Its temperature needs fluctuate between 19 and 10 °C on average a year. This tree accepts from subtropical to cool climate.
Pinus monophylla, the single-leaf pinyon, is a pine in the pinyon pine group, native to North America. The range is in southernmost Idaho, western Utah, Arizona, southwest New Mexico, Nevada, eastern and southern California and northern Baja California.
Pinus armandii, the Armand pine or Chinese white pine, is a species of pine native to China, occurring from southern Shanxi west to southern Gansu and south to Yunnan, with outlying populations in Anhui. It grows at altitudes of 2200–3000 m in Taiwan, and it also extends a short distance into northern Burma. In Chinese it is known as "Mount Hua pine" (华山松).
Pinus dalatensis, also known as Vietnamese white pine or Dalat pine, is a species of pine endemic to Indochina. In Vietnam it grows in the mountains of the central and south-central parts of the country at elevations of 1,400 to 2,300 metres. Only recently confirmed from Laos, the population located within the Nakai-Nam Theun Biodiversity Conservation Area is the largest, at the lowest elevation, and the northernmost of the known populations of P. dalatensis.
In plant morphology, thorns, spines, and prickles, and in general spinose structures, are hard, rigid extensions or modifications of leaves, roots, stems, or buds with sharp, stiff ends, and generally serve the same function: physically deterring animals from eating the plant material.
Both naturally and artificially occurring pine species (Pinus) can hybridize, combining their genetic material and sometimes creating hybrids that can be more or less vigorous than their parent species. An example of a naturally occurring hybrid pine is Pinus × sondereggeri, a naturally occurring cross between loblolly pine and longleaf pine. An example of the many artificial hybrids is Pinus lambertiana × P. armandii.