Digitaria is a genus of plants in the grass family native to tropical and warm temperate regions. Common names include crabgrass, finger-grass, fonio, they are slender monocotyledonous annual and perennial lawn and forage plants. Digitus is the Latin word for "finger", they are distinguished by the long, finger-like inflorescences they produce. Digitaria species occur in tropical and temperate regions of both hemispheres. Though some Digitaria species are weeds, others have uses as food; the seeds, most notably those of fonio, can be toasted and ground into a flour, which can be used to make porridge or fermented to make beer. Fonio has been used as a staple crop in parts of Africa, it has decent nutrient qualities as a forage for cattle. The prevalent species of Digitaria in North America are large crabgrass, sometimes known as hairy crabgrass; these species become problem weeds in lawns and gardens, growing well in thin lawns that are watered underfertilized, poorly drained. They are annual plants, one plant is capable of producing 150,000 seeds per season.
The seeds germinate in the late spring and early summer and outcompete the domesticated lawn grasses, expanding outward in a circle up to 30 cm in diameter. In the autumn when the plants die, they leave large voids in the lawn; the voids become prime areas for the crabgrass seeds to germinate the following season. Biological control is preferable over herbicide use on lawns, as crabgrass emergence is not the cause of poor lawn health but a symptom, it will return annually if the lawn is not restored with fertilization and proper watering. Crabgrass is outcompeted by healthy lawn grass because, as an annual plant, crabgrass dies off in autumn and needs open conditions for its germination the following spring. Data related to Digitaria at Wikispecies Media related to Digitaria at Wikimedia Commons
Amygdaloideae is a subfamily within the flowering plant family Rosaceae. It was considered by some authors to be separate from Rosaceae, the family names Prunaceae and Amygdalaceae have been used. Reanalysis from 2007 has shown that the previous definition of subfamily Spiraeoideae was paraphyletic. To solve this problem, a larger subfamily was defined that includes the former Amygdaloideae and Maloideae; this subfamily, however, is to be called Amygdaloideae rather than Spiraeoideae under the International Code of Nomenclature for algae and plants as updated in 2011. As traditionally defined, the Amygdaloideae includes such commercially important crops as plum, apricot and almond; the fruit of these plants are known as stone fruit, as each fruit contains a hard shell called a stone or pit, which contains the single seed. The expanded definition of the Amygdaloideae adds to these commercially important crops such as apples and pears that have pome fruit, important ornamental plants such as Spiraea and Aruncus that have hard dry fruits.
The name Prunoideae is incorrect. The 1835 publication of that name by Gilbert Thomas Burnett is invalid because it lacks a description. Paul Fedorowitsch Horaninow published the name in 1847, but Amygdaloideae, published in 1832 by George Arnott Walker Arnott, has priority and is therefore the correct name; the taxonomy of this group of plants within the Rosaceae has been unclear. In 2001 it was reported that Amygdaloideae sensu stricto consists of two distinct genetic groups or "clades", Prunus–Maddenia and Exochorda–Oemleria–Prinsepia. Further refinement shows that Exochorda–Oemleria–Prinsepia is somewhat separate from Prunus–Maddenia–Pygeum, that the traditional subfamilies Maloideae and Spiraeoideae must be included in Amygdaloideae if a paraphyletic group is to be avoided. With this classification, the genus Prunus is considered to include Armeniaca, Amygdalus, Laurocerasus and Maddenia. Robert Frost alluded to the merging of Amygdalaceae into Rosaceae in his poem The Rose Family, when he wrote "The rose is a rose and was always a rose / But the theory now goes that the apple's a rose, / and the pear is, so's the plum, I suppose."
In the next line he wrote, "The dear only knows what will next prove a rose." This referred to shifting botanical opinion which had reunited Amygdalaceae and Malaceae into Rosaceae. A recent classification places the following genera in the subfamily: Media related to Amygdaloideae at Wikimedia Commons
A raceme is an unbranched, indeterminate type of inflorescence bearing pedicellate flowers along its axis. In botany, an axis means a shoot, in this case one bearing the flowers. In indeterminate inflorescence-like racemes, the oldest flowers are borne towards the base and new flowers are produced as the shoot grows, with no predetermined growth limit. A plant that flowers on a showy raceme may have this reflected in its scientific name, e.g. Cimicifuga racemosa. A compound raceme called a panicle, has a branching main axis. Examples of racemes occur on radish plants. A spike is an unbranched, indeterminate inflorescence, similar to a raceme, but bearing sessile flowers. Examples occur on Malabar chaff flowers. A spikelet can refer to a small spike, although it is used to refer to the ultimate flower cluster unit in grasses and sedges, in which case the stalk supporting the cluster becomes the pedicel. A true spikelet comprises one or more florets enclosed by two glumes, with flowers and glumes arranged in two opposite rows along the spikelet.
Examples grasses. An ament or catkin is similar to a spike or raceme, "but with subtending bracts so conspicuous as to conceal the flowers until pollination, as in the pussy–willow, birch...". These are sometimes called amentaceous plants. A spadix is a form of spike in which the florets are densely crowded along a fleshy axis, enclosed by one or more large, brightly–colored bracts called spathes; the female flowers grow at the base, male flowers grow above. They are a characteristic of the Araceae family, for example jack -- in -- wild calla. From classical Latin racemus, cluster of grapes. Inflorescence Glossary of botanical terms
A pedicel is a stem that attaches a single flower to the inflorescence. In the absence of a pedicel, the flowers are described as sessile. Pedicel is applied to the stem of the infructescence; the word "pedicel" is derived from the latin pediculus, meaning "little foot". The stem or branch from the main stem of the inflorescence that holds a group of pedicels is called a peduncle. In Halloween types of pumpkin or squash plants, the shape of the pedicel has received particular attention because plant breeders are trying to optimize the size and shape of the pedicel for the best "lid" for a "jack-o'-lantern". Sessile Scape Terminology for Asteraceae
Lychee is the sole member of the genus Litchi in the soapberry family, Sapindaceae. It is a tropical tree native to the Guangdong and Fujian provinces of China, where cultivation is documented from 1059 AD. China is the main producer of lychees, followed by India, other countries in Southeast Asia, the Indian Subcontinent and South Africa. A tall evergreen tree, the lychee bears small fleshy fruits; the outside of the fruit is pink-red textured and inedible, covering sweet flesh eaten in many different dessert dishes. Lychee seeds contain methylenecyclopropylglycine which can cause hypoglycemia associated with outbreaks of encephalopathy in undernourished Indian and Vietnamese children who had consumed lychee fruit. Litchi chinensis is the sole member of the genus Litchi in Sapindaceae, it was described and named by French naturalist Pierre Sonnerat in his account "Voyage aux Indes orientales et à la Chine, fait depuis 1774 jusqu'à 1781", published in 1782. There are three subspecies, determined by flower arrangement, twig thickness and number of stamens.
Litchi chinensis subsp. Chinensis is the only commercialized lychee, it grows wild in southern China, northern Vietnam, Cambodia. It has thin twigs, flowers have six stamens, fruit are smooth or with protuberances up to 2 mm. Litchi chinensis subsp. Philippinensis Leenh, it is common in the wild in the Philippines and cultivated. It has thin twigs, six to seven stamens, long oval fruit with spiky protuberances up to 3 mm. Litchi chinensis subsp. Javensis, it is only known in Malaysia and Indonesia. It has thick twigs, flowers with seven to eleven stamens in sessile clusters, smooth fruit with protuberances up to 1 mm. Litchi chinensis is an evergreen tree, less than 15 m tall, sometimes reaching 28 m, its evergreen leaves, 5 to 8 in long, are pinnate, having 4 to 8 alternate, elliptic-oblong to lanceolate, abruptly pointed, The bark is grey-black, the branches a brownish-red. Its evergreen leaves are 12.5 to 20 cm long, with leaflets in two to four pairs. Lychee have a similar foliage to the Lauraceae family due to convergent evolution.
They are adapted by developing leaves that repel water, are called laurophyll or lauroid leaves. Flowers grow on a terminal inflorescence with many panicles on the current season's growth; the panicles grow in clusters of ten or more, reaching 10 to 40 cm or longer, holding hundreds of small white, yellow, or green flowers that are distinctively fragrant. The lychee bears fleshy fruits that mature in 80–112 days depending on climate and cultivar. Fruits vary in shape from round to ovoid to heart-shaped, up to 5 cm long and 4 cm wide, weighing 20 g; the thin, tough skin is green when immature, ripening to red or pink-red, is smooth or covered with small sharp protuberances textured. The rind is inedible but removed to expose a layer of translucent white fleshy aril with a floral smell and a fragrant, sweet flavor; the skin turns dry when left out after harvesting. The fleshy, edible portion of the fruit is an aril, surrounding one dark brown inedible seed, 1 to 3.3 cm long and 0.6 to 1.2 cm wide.
Some cultivars produce a high percentage of fruits with shriveled aborted seeds known as'chicken tongues'. These fruit have a higher price, due to having more edible flesh. Since the perfume-like flavour is lost in the process of canning, the fruit is eaten fresh. Cultivation of lychee began in the region of southern China, going back to 1059 AD, northern Vietnam. Unofficial records in China refer to lychee as far back as 2000 BC. Wild trees still grow on Hainan Island. There are many stories of the fruit's use as a delicacy in the Chinese Imperial Court, it was first described and introduced to the West in 1656 by Michal Boym, a Polish Jesuit missionary. In the 1st century, fresh lychees were in such demand at the Imperial Court that a special courier service with fast horses would bring the fresh fruit from Guangdong. There was great demand for lychee in the Song Dynasty, in his Li chi pu, it was the favourite fruit of Emperor Li Longji's favoured concubine Yang Yuhuan. The emperor had the fruit delivered at great expense to the capital.
The lychee attracted attention of European travellers, such as Juan González de Mendoza in his History of the great and mighty kingdom of China, based on the reports of Spanish friars who had visited China in the 1570s gave the fruit high praise: hey haue a kinde of plummes, that they doo call lechias, that are of an exceeding gallant tast, neuer hurteth any body, although they shoulde eate a great number of them. Lychees are extensively grown in China, Thailand and the rest of tropical Southeast Asia, the Indian Subcontinent, in South Africa, the Caribbean, Australia and the southeastern United States, they require a tropical climate, frost-free and is not below the temperature of −4 °C. Lychees require a climate with high summer heat and humidity. Growth is best on well-drained acidic soils rich in organic matter and mulch. A wide range of cultivars are available, with early and late maturing forms suited to warmer and cooler climates, respectively, they are grown as an ornamenta
An inflorescence is a group or cluster of flowers arranged on a stem, composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants; the modifications can involve the length and the nature of the internodes and the phyllotaxis, as well as variations in the proportions, swellings, adnations and reduction of main and secondary axes. Inflorescence can be defined as the reproductive portion of a plant that bears a cluster of flowers in a specific pattern; the stem holding the whole inflorescence is called a peduncle and the major axis holding the flowers or more branches within the inflorescence is called the rachis. The stalk of each single flower is called a pedicel. A flower, not part of an inflorescence is called a solitary flower and its stalk is referred to as a peduncle. Any flower in an inflorescence may be referred to as a floret when the individual flowers are small and borne in a tight cluster, such as in a pseudanthium.
The fruiting stage of an inflorescence is known as an infructescence. Inflorescences may be complex; the rachis may be one of several types, including single, umbel, spike or raceme. Inflorescences are described by many different characteristics including how the flowers are arranged on the peduncle, the blooming order of the flowers and how different clusters of flowers are grouped within it; these terms are general representations. Inflorescences have modified shoots foliage different from the vegetative part of the plant. Considering the broadest meaning of the term, any leaf associated with an inflorescence is called a bract. A bract is located at the node where the main stem of the inflorescence forms, joined to the main stem of the plant, but other bracts can exist within the inflorescence itself, they serve a variety of functions which include protecting young flowers. According to the presence or absence of bracts and their characteristics we can distinguish: Ebracteate inflorescences: No bracts in the inflorescence.
Bracteate inflorescences: The bracts in the inflorescence are specialised, sometimes reduced to small scales, divided or dissected. Leafy inflorescences: Though reduced in size, the bracts are unspecialised and look like the typical leaves of the plant, so that the term flowering stem is applied instead of inflorescence; this use is not technically correct, as, despite their'normal' appearance, these leaves are considered, in fact, bracts, so that'leafy inflorescence' is preferable. Leafy-bracted inflorescences: Intermediate between bracteate and leafy inflorescence. If many bracts are present and they are connected to the stem, like in the family Asteraceae, the bracts might collectively be called an involucre. If the inflorescence has a second unit of bracts further up the stem, they might be called an involucel. Plant organs can grow according to two different schemes, namely monopodial or racemose and sympodial or cymose. In inflorescences these two different growth patterns are called indeterminate and determinate and indicate whether a terminal flower is formed and where flowering starts within the inflorescence.
Indeterminate inflorescence: Monopodial growth. The terminal bud keeps forming lateral flowers. A terminal flower is never formed. Determinate inflorescence: Sympodial growth; the terminal bud forms a terminal flower and dies out. Other flowers grow from lateral buds. Indeterminate and determinate inflorescences are sometimes referred to as open and closed inflorescences respectively; the indeterminate patterning of flowers is derived from determinate flowers. It is suggested that indeterminate flowers have a common mechanism that prevents terminal flower growth. Based on phylogenetic analyses, this mechanism arose independently multiple times in different species. In an indeterminate inflorescence there is no true terminal flower and the stem has a rudimentary end. In many cases the last true flower formed by the terminal bud straightens up, appearing to be a terminal flower. A vestige of the terminal bud may be noticed higher on the stem. In determinate inflorescences the terminal flower is the first to mature, while the others tend to mature starting from the bottom of the stem.
This pattern is called acropetal maturation. When flowers start to mature from the top of the stem, maturation is basipetal, while when the central mature first, divergent; as with leaves, flowers can be arranged on the stem according to many different patterns. See'Phyllotaxis' for in-depth descriptions Similarly arrangement of leaf in bud is called Ptyxis. Metatopy is the placement of organs out of their expected position: metatopy occurs in inflorescences when unequal growth rates alter different areas of the axis and the organs attached to the axis; when a single or a cluster of flower is located at the axil of a bract, the location of the bract in relation to the stem holding the flower is indicated by the use of different terms and may be a useful diagnostic indicator. Typical placement of bracts include: Some plants have bracts that subtend the inflorescence, where the flowers are on branched stalks.
The rowans or mountain-ashes are shrubs or trees in the genus Sorbus of the rose family, Rosaceae. They are native throughout the cool temperate regions of the Northern Hemisphere, with the highest species diversity in the mountains of western China and the Himalaya, where numerous apomictic microspecies occur; the name rowan was applied to the species Sorbus aucuparia and is used for other species in Sorbus subgenus Sorbus. When a wider variety of fruits were eaten in Europe and North America, Sorbus was a domestically used fruit throughout these regions, it is still used in some countries, but Sorbus domestica, for example, has vanished from Britain, where it was traditionally appreciated. Natural hybrids including Sorbus aucuparia and the whitebeam, Sorbus aria, give rise to many endemic variants in the UK; the traditional names of the rowan are those applied to the species Sorbus aucuparia, Sorbus torminalis, Sorbus domestica. The Latin name sorbus was borrowed into Old English as syrfe; the name "service-tree" for Sorbus domestica is derived from that name by folk etymology.
The Latin name sorbus is from a root for "red, reddish-brown". Sorbus domestica is known as "whitty pear", the adjective whitty meaning "pinnate"; the name "mountain-ash" for Sorbus domestica is due to a superficial similarity of the rowan leaves to those of the ash, not to be confused with Fraxinus ornus, a true ash, known as "mountain ash". Sorbus torminalis is known as "chequer tree"; the name "rowan" is recorded from 1804, detached from an earlier rowan-tree, attested from the 1540s in northern dialects of English and Scots. It is from a North Germanic source, derived from Old Norse reynir from the Germanic verb *raud-inan "to redden", in reference to the berries. Various dialectal variants of rowan are found in English, including ran, rodan, royne and rune; the Old English name of the rowan is cwic-beám. This name by the 19th century was reinterpreted as connected to the word witch, from a dialectal variant wick for quick and names such as wicken-tree, wich-tree and wiggan-tree, giving rise to names such as witch-hazel and witch-tree.
The Old Irish name is reflected in Modern Irish caorann. The "arboreal" Bríatharogam in the Book of Ballymote associates the rowan with the letter luis, with the gloss "delightful to the eye is luis, i.e. rowan, owing to the beauty of its berries". Due to this, "delight of the eye" has been reported as a "name of the rowan" by some commentators. In the Canadian provinces of Newfoundland and Labrador and Nova Scotia, this species is referred to as a "dogberry" tree. In German, Sorbus aucuparia is known as Eberesche; the latter is a compound of the name of the ash tree with what is contemporarily the name of the boar, but in fact the continuation of a Gaulish name, eburo-. The Welsh name criafol refers to the tree as "lamenting fruit", associating the red fruit with the blood of Christ, as Welsh tradition believed the Cross was carved from the wood of this tree. Rowans are small deciduous trees 10–20 m tall, though a few are shrubs. Rowans are unrelated to the true ash trees of family Oleaceae. Though their leaves are superficially similar, those of Sorbus are alternate, while those of Fraxinus are opposite.
Rowan leaves are arranged alternately, are pinnate, with 11–35 leaflets. A terminal leaflet is always present; the flowers are borne in dense corymbs. The fruit is a small pome 4–8 mm diameter, bright orange or red in most species, but pink, yellow or white in some Asian species; the fruit are soft and juicy, which makes them a good food for birds waxwings and thrushes, which distribute the rowan seeds in their droppings. Due to their small size the fruits are referred to as berries, but a true berry is a simple fruit produced from a single ovary, whereas a pome is an accessory fruit. Rowan is used as a food plant by the larvae of some Lepidoptera species; the best-known species is the European rowan Sorbus aucuparia, a small tree 4–12 m tall growing in a variety of habitats throughout northern Europe and in mountains in southern Europe and southwest Asia. Its berries are a favourite food for many birds and are a traditional wild-collected food in Britain and Scandinavia, it is one of the hardiest European trees, occurring to 71° north in Vardø in Arctic Norway, has become naturalised in northern North America.
The greatest diversity of form as well as the largest number of rowan species is in Asia, with distinctive species such as Sargent's rowan Sorbus sargentiana with large leaves 20–35 cm long and 15–20 cm broad and large corymbs with 200–500 flowers, at the other extreme, small-leaf rowan Sorbus microphylla with leaves 8–12 cm long and 2.5–3 cm broad. While most are trees, the dwar