A sepal is a part of the flower of angiosperms. Green, sepals function as protection for the flower in bud, as support for the petals when in bloom; the term sepalum was coined by Noël Martin Joseph de Necker in 1790, derived from the Greek σκεπη, a covering. Collectively the sepals are called the outermost whorl of parts that form a flower; the word calyx was adopted from the Latin calyx, not to be confused with a cup or goblet. Calyx derived from the Greek κάλυξ, a bud, a calyx, a husk or wrapping, while calix derived from the Greek κυλιξ, a cup or goblet, the words have been used interchangeably in botanical Latin. After flowering, most plants have no more use for the calyx which becomes vestigial; some plants retain a thorny calyx, either dried or live, as protection for seeds. Examples include species of Acaena, some of the Solanaceae, the water caltrop, Trapa natans. In some species the calyx not only persists after flowering, but instead of withering, begins to grow until it forms a bladder-like enclosure around the fruit.
This is an effective protection against some kinds of birds and insects, for example in Hibiscus trionum and the Cape gooseberry. Morphologically, both sepals and petals are modified leaves; the calyx and the corolla are the outer sterile whorls of the flower, which together form what is known as the perianth. The term tepal is applied when the parts of the perianth are difficult to distinguish, e.g. the petals and sepals share the same color, or the petals are absent and the sepals are colorful. When the undifferentiated tepals resemble petals, they are referred to as "petaloid", as in petaloid monocots, orders of monocots with brightly coloured tepals. Since they include Liliales, an alternative name is lilioid monocots. Examples of plants in which the term tepal is appropriate include genera such as Tulipa. In contrast, genera such as Rosa and Phaseolus have well-distinguished petals; the number of sepals in a flower is its merosity. Flower merosity is indicative of a plant's classification.
The merosity of a eudicot flower is four or five. The merosity of a monocot or palaeodicot flower is a multiple of three; the development and form of the sepals vary among flowering plants. They may be fused together; the sepals are much reduced, appearing somewhat awn-like, or as scales, teeth, or ridges. Most such structures protrude until the fruit is mature and falls off. Examples of flowers with much reduced perianths are found among the grasses. In some flowers, the sepals are fused towards the base. In other flowers a hypanthium includes the bases of sepals and the attachment points of the stamens. Plant morphology
The Lecythidaceae comprise a family of about 20 genera and 250-300 species of woody plants native to tropical South America, Africa and Australia. According to the most recent molecular analysis of Lecythidaceae by Mori et al. the three subfamilies are: Foetidioideae from Madagascar include only Foetidia. Planchonioideae are restricted to the Old World tropics. Lecythidoideae are restricted to the New World tropics. Two other families are sometimes included in Lecythidaceae. More detailed information about Lecythidaceae the New World taxa, can be found at the Lecythidaceae Pages; the most important member of the family in world trade is the Brazil nut, valued for its edible nuts. The APG II system of 2003 includes genera from the family Scytopetalaceae in the Lecythidaceae, including Rhaptopetalum and Brazzeia. Careya is called pezham in Malayalam. Abdulmajidia Whitmore as Barringtoniaceae sensu Takhtajan 1997 Allantoma Miers Asteranthos Desf. as Asteranthaceae Barringtonia J. R. Forst. & G. Forst.
As Barringtoniaceae Bertholletia Bonpl. Brazzeia Verc. Careya Roxb. as Barringtoniaceae Cariniana Casar. Chydenanthus Miers as Barringtoniaceae Corythophora R. Knuth Couratari Aubl. Couroupita Aubl. Crateranthus Baker f. incertae sedis according to Takhtajan Napoleonaeaceae Eschweilera Mart. Ex DC. Foetidia Comm. Ex Lam. as Foetidiaceae Grias L. Gustavia L. Lecythis Loefl. Napoleonaea P. Beauv; also as Napoleonaeaceae Petersianthus Merr. as Barringtoniaceae Pierrina Engl. Planchonia Blume as Barringtoniaceae Rhaptopetalum Oliv. Scytopetalum Engl. Lecythidaceae in L. Watson and M. J. Dallwitz; the families of flowering plants. Http://delta-intkey.com Barringtoniaceae in L. Watson and M. J. Dallwitz; the families of flowering plants. Http://delta-intkey.com Foetidiaceae in L. Watson and M. J. Dallwitz; the families of flowering plants. Http://delta-intkey.com Asteranthaceae in L. Watson and M. J. Dallwitz; the families of flowering plants. Http://delta-intkey.com Napoleonaeaceae in L. Watson and M. J. Dallwitz; the families of flowering plants.
Http://delta-intkey.com The Lecythidaceae Pages by Scott A. Mori and Ghillean T. Prance Toa Alta, Puerto Rico Lecythidaceae in BoDD – Botanical Dermatology Database
The Amazon River in South America is the largest river by discharge volume of water in the world, by some definitions it is the longest. The headwaters of the Apurímac River on Nevado Mismi had been considered for nearly a century as the Amazon's most distant source, until a 2014 study found it to be the headwaters of the Mantaro River on the Cordillera Rumi Cruz in Peru; the Mantaro and Apurímac join, with other tributaries form the Ucayali River, which in turn meets the Marañón River upstream of Iquitos, Peru, to form what countries other than Brazil consider to be the main stem of the Amazon. Brazilians call this section the Solimões River above its confluence with the Rio Negro to form what Brazilians call the Amazon at the Meeting of Waters at Manaus, the river's largest city. At an average discharge of about 209,000 cubic metres per second —approximately 6,591 cubic kilometres per annum, greater than the next seven largest independent rivers combined—the Amazon represents 20% of the global riverine discharge to the ocean.
The Amazon basin is the largest drainage basin in the world, with an area of 7,050,000 square kilometres. The portion of the river's drainage basin in Brazil alone is larger than any other river's basin; the Amazon enters Brazil with only one-fifth of the flow it discharges into the Atlantic Ocean, yet has a greater flow at this point than the discharge of any other river. The river was known by Europeans as the Marañón and the Peruvian part of the river is still known by that name today, it became known as the Rio Amazonas in Spanish and Portuguese, or The Amazon in English. The name Rio Amazonas was given after native warriors attacked a 16th-century expedition by Francisco de Orellana; the warriors were led by women, reminding de Orellana of the Amazon warriors, a tribe of women warriors related to Iranian Scythians and Sarmatians mentioned in Greek mythology. The word Amazon itself may be derived from the Iranian compound *ha-maz-an- " fighting together" or ethnonym *ha-mazan- "warriors", a word attested indirectly through a derivation, a denominal verb in Hesychius of Alexandria's gloss "ἁμαζακάραν· πολεμεῖν.
Πέρσαι", where it appears together with the Indo-Iranian root *kar- "make". During what many archaeologists call the formative stage, Amazonian societies were involved in the emergence of South America's highland agrarian systems; the trade with Andean civilisations in the terrains of the headwaters in the Andes, formed an essential contribution to the social and religious development of the higher altitude civilisations of among others the Muisca and Incas. Early human settlements were based on low-lying hills or mounds. Shell mounds were the earliest evidence of habitation, they are associated with ceramic age cultures. Artificial earth platforms for entire villages are the second type of mounds, they are best represented by the Marajoara culture. Figurative mounds are the most recent types of occupation. There is ample evidence that the areas surrounding the Amazon River were home to complex and large-scale indigenous societies chiefdoms who developed large towns and cities. Archaeologists estimate that by the time the Spanish conquistador De Orellana traveled across the Amazon in 1541, more than 3 million indigenous people lived around the Amazon.
These pre-Columbian settlements created developed civilizations. For instance, pre-Columbian indigenous people on the island of Marajó may have developed social stratification and supported a population of 100,000 people. In order to achieve this level of development, the indigenous inhabitants of the Amazon rainforest altered the forest's ecology by selective cultivation and the use of fire. Scientists argue that by burning areas of the forest repetitiously, the indigenous people caused the soil to become richer in nutrients; this created dark soil areas known as terra preta de índio. Because of the terra preta, indigenous communities were able to make land fertile and thus sustainable for the large-scale agriculture needed to support their large populations and complex social structures. Further research has hypothesized; some say that its effects on forest ecology and regional climate explain the otherwise inexplicable band of lower rainfall through the Amazon basin. Many indigenous tribes engaged in constant warfare.
James Stuart Olson wrote: "The Munduruku expansion dislocated and displaced the Kawahíb, breaking the tribe down into much smaller groups... first came to the attention of Europeans in 1770 when they began a series of widespread attacks on Brazilian settlements along the Amazon River." In March 1500, Spanish conquistador Vicente Yáñez Pinzón was the first documented European to sail up the Amazon River. Pinzón called the stream Río Santa María del Mar Dulce shortened to Mar Dulce sweet sea, because of its fresh water pushing out into the ocean. Another Spanish explorer, Francisco de Orellana, was the first European to travel from the origins of the upstream river basins, situated in the Andes, to the mouth of the river. In this journey, Orellana baptised some of the affluents of the Amazonas like Rio Negro and Jurua; the name Amazonas is taken from the native warriors that attacked this expedition women, that reminded De Orellana of the mythical female Amazon warriors from the
An anvil is a metalworking tool consisting of a large block of metal, with a flattened top surface, upon which another object is struck. Anvils are as massive as is practical, because the higher their inertia, the more efficiently they cause the energy of striking tools to be transferred to the work piece. In most cases the anvil is used as a forging tool. Before the advent of modern welding technology, it was a primary tool of metal workers; the great majority of modern anvils are made of cast or forged steel, heat treated. Inexpensive anvils have been made of cast iron and low quality steel, but are considered unsuitable for serious use as they deform and lack rebound when struck; because anvils are ancient tools and were at one time commonplace, they have acquired symbolic meaning beyond their use as utilitarian objects. They have found their way into popular culture including episodes of Looney Tunes, the name of a heavy metal band, usage by blacksmiths as well as jewelers and metal smiths.
The primary work surface of the anvil is known as the face. It is made of hardened steel and should be flat and smooth with rounded edges for most work. Any marks on the face will be transferred to the work. Sharp edges tend to cut into the metal being worked and may cause cracks to form in the workpiece; the face is hardened and tempered to resist the blows of the smith's hammer, so the anvil face does not deform under repeated use. A hard anvil face reduces the amount of force lost in each hammer blow. Hammers and work pieces of hardened steel should never directly strike the anvil face with full force, as they may damage it; the horn of the anvil is a conical projection used to form various round shapes and is unhardened steel or iron. The horn is used in bending operations, it is used by some smiths as an aid in "drawing down" stock. Some anvils European, are made with two horns, one square and one round; some anvils are made with side horns or clips for specialized work. The step is that area of the anvil between the "horn" and the "face".
It is used for cutting. The hardie hole is a square hole into which specialized forming and cutting tools, called Hardy tools, are placed, it is used in punching and bending operations. The pritchel hole is a small round hole, present on most modern anvils; some anvils have more than one. It is used for punching. At times, smiths will fit a second tool to this hole to allow the smith more flexibility when using more than one anvil tool. An anvil needs to be placed upon a sturdy base made from an fire resistant material, it requires being fastened to the base, so it will not move when struck with a hammer. A loose anvil is unsafe, as it can fall off the base and is an ineffective forging tool. Common methods of attaching an anvil are spikes, steel or iron straps, bolts where there are holes provided, cables. A smith would use whatever was at hand, as long as it held the anvil in place; the anvil is placed as near to the forge as is convenient no more than one step from the forge to prevent heat loss in the work piece.
The most common base traditionally was a hard wood log or large timber buried several feet into the floor of the forge shop floor. This was done to make the anvil immobile when heavy bending were done upon the anvil. In the industrial era cast iron bases became available, they had the advantage of adding additional weight to the anvil, making it more stable while making the anvil movable. These bases are sought after by collectors today; when concrete became available, there was a trend to make steel reinforced anvil bases by some smiths, though this practice has been abandoned. In more modern times many anvils have been placed upon bases fabricated from steel a short thick section of a large I-Beam. In addition, bases have been made from dimensional lumber bolted together to form a large block or steel drums full of oil-saturated sand to provide a damping effect. In recent times tripod bases of fabricated steel have become popular with some smiths. There are many designs for anvils, which are tailored for a specific purpose or to meet the needs of a particular smith.
For example, there were anvils made for farriers, general smiths, chain makers, saw tuners, coach makers and many other types of metal workers. Such designs have originated in diverse geographic locations; the common blacksmith's anvil is made of either forged or cast steel, forged wrought iron with a hard steel face or cast iron with a hard steel face. Cast iron anvils are not used for forging as they are incapable of standing up to the impact and will crack and dent. Cast iron anvils without a hard steel face do not have the rebound that a harder anvil would and will tire out the smith; some anvils have been made with a smooth top working face of hardened steel welded to a cast iron or wrought iron body, though this manufacturing method is no longer in use. At one end, the common smith's anvil has a projecting conical bick used for hammering curved work pieces; the other end is called the heel. The other end is provided with a bick rectangular in section. Most anvils made since the late 18th century have a hardy hole
Indigenous peoples of the Americas
The indigenous peoples of the Americas are the Pre-Columbian peoples of North and South America and their descendants. Although some indigenous peoples of the Americas were traditionally hunter-gatherers—and many in the Amazon basin, still are—many groups practiced aquaculture and agriculture; the impact of their agricultural endowment to the world is a testament to their time and work in reshaping and cultivating the flora indigenous to the Americas. Although some societies depended on agriculture, others practiced a mix of farming and gathering. In some regions the indigenous peoples created monumental architecture, large-scale organized cities, city-states, states and empires. Among these are the Aztec and Maya states that until the 16th century were among the most politically and advanced nations in the world, they had a vast knowledge of engineering, mathematics, writing, medicine and irrigation, mining and goldsmithing. Many parts of the Americas are still populated by indigenous peoples.
At least a thousand different indigenous languages are spoken in the Americas. Some, such as the Quechuan languages, Guaraní, Mayan languages and Nahuatl, count their speakers in millions. Many maintain aspects of indigenous cultural practices to varying degrees, including religion, social organization and subsistence practices. Like most cultures, over time, cultures specific to many indigenous peoples have evolved to incorporate traditional aspects but cater to modern needs; some indigenous peoples still live in relative isolation from Western culture and a few are still counted as uncontacted peoples. Indigenous peoples of the United States are known as Native Americans or American Indians and Alaska Natives. Application of the term "Indian" originated with Christopher Columbus, who, in his search for India, thought that he had arrived in the East Indies; those islands came to be known as the "West Indies", a name still used. This led to the blanket term "Indies" and "Indians" for the indigenous inhabitants, which implied some kind of racial or cultural unity among the indigenous peoples of the Americas.
This unifying concept, codified in law and politics, was not accepted by the myriad groups of indigenous peoples themselves, but has since been embraced or tolerated, by many over the last two centuries. Though the term "Indian" does not include the culturally and linguistically distinct indigenous peoples of the Arctic regions of the Americas—such as the Aleuts, Inuit or Yupik peoples, who entered the continent as a second more recent wave of migration several thousand years before and have much more recent genetic and cultural commonalities with the aboriginal peoples of the Asiatic Arctic Russian Far East—these groups are nonetheless considered "indigenous peoples of the Americas". Indigenous peoples are known in Canada as Aboriginal peoples, which includes not only First Nations and Arctic Inuit, but the minority population of First Nations-European mixed race Métis people who identify culturally and ethnically with indigenous peoplehood; this is contrasted, for instance, to the American Indian-European mixed race mestizos of Hispanic America who, with their larger population, identify as a new ethnic group distinct from both Europeans and Indigenous Americans, but still considering themselves a subset of the European-derived Hispanic or Brazilian peoplehood in culture and ethnicity.
The term Amerindian and its cognates find preferred use in scientific contexts and in Quebec, the Guianas and the English-speaking Caribbean. Indígenas or pueblos indígenas is a common term in Spanish-speaking countries and pueblos nativos or nativos may be heard, while aborigen is used in Argentina and pueblos originarios is common in Chile. In Brazil, indígenas or povos indígenas are common if formal-sounding designations, while índio is still the more often-heard term and aborígene and nativo being used in Amerindian-specific contexts; the Spanish and Portuguese equivalents to Indian could be used to mean any hunter-gatherer or full-blooded Indigenous person to continents other than Europe or Africa—for example, indios filipinos. The specifics of Paleo-Indian migration to and throughout the Americas, including the exact dates and routes traveled, are the subject of ongoing research and discussion. According to archaeological and genetic evidence and South America were the last continents in the world to gain human habitation.
During the Wisconsin glaciation, 50–17,000 years ago, falling sea levels allowed people to move across the land bridge of Beringia that joined Siberia to northwest North America. Alaska was a glacial refugium; the Laurentide Ice Sheet covered most of North America, blocking nomadic inhabitants and confining them to Alaska for thousands of years. Indigenous genetic studies suggest that the first inhabitants of the Americas share a single ancestral population, one that developed in isolation, conjectured to be Beringia; the isolat
Cuba the Republic of Cuba, is a country comprising the island of Cuba as well as Isla de la Juventud and several minor archipelagos. Cuba is located in the northern Caribbean where the Caribbean Sea, Gulf of Mexico and Atlantic Ocean meet, it is east of the Yucatán Peninsula, south of both the U. S. state of Florida and the Bahamas, west of Haiti and north of both Jamaica and the Cayman Islands. Havana is capital; the area of the Republic of Cuba is 110,860 square kilometres. The island of Cuba is the largest island in Cuba and in the Caribbean, with an area of 105,006 square kilometres, the second-most populous after Hispaniola, with over 11 million inhabitants; the territory, now Cuba was inhabited by the Ciboney Taíno people from the 4th millennium BC until Spanish colonisation in the 15th century. From the 15th century, it was a colony of Spain until the Spanish–American War of 1898, when Cuba was occupied by the United States and gained nominal independence as a de facto United States protectorate in 1902.
As a fragile republic, in 1940 Cuba attempted to strengthen its democratic system, but mounting political radicalization and social strife culminated in a coup and subsequent dictatorship under Fulgencio Batista in 1952. Open corruption and oppression under Batista's rule led to his ousting in January 1959 by the 26th of July Movement, which afterwards established communist rule under the leadership of Fidel Castro. Since 1965, the state has been governed by the Communist Party of Cuba; the country was a point of contention during the Cold War between the Soviet Union and the United States, a nuclear war nearly broke out during the Cuban Missile Crisis of 1962. Cuba is one of few Marxist–Leninist socialist states, where the role of the vanguard Communist Party is enshrined in the Constitution. Independent observers have accused the Cuban government of numerous human rights abuses, including arbitrary imprisonment. Culturally, Cuba is considered part of Latin America, it is a multiethnic country whose people and customs derive from diverse origins, including the aboriginal Taíno and Ciboney peoples, the long period of Spanish colonialism, the introduction of African slaves and a close relationship with the Soviet Union in the Cold War.
Cuba is a sovereign state and a founding member of the United Nations, the G77, the Non-Aligned Movement, the African and Pacific Group of States, ALBA and Organization of American States. The country is a middle power in world affairs, it has one of the world's only planned economies, its economy is dominated by the exports of sugar, tobacco and skilled labor. According to the Human Development Index, Cuba has high human development and is ranked the eighth highest in North America, though 67th in the world, it ranks in some metrics of national performance, including health care and education. It is the only country in the world to meet the conditions of sustainable development put forth by the WWF. Historians believe the name Cuba comes from the Taíno language, however "its exact derivation unknown"; the exact meaning of the name is unclear but it may be translated either as'where fertile land is abundant', or'great place'. Fringe theory writers who believe that Christopher Columbus was Portuguese state that Cuba was named by Columbus for the town of Cuba in the district of Beja in Portugal.
Before the arrival of the Spanish, Cuba was inhabited by three distinct tribes of indigenous peoples of the Americas. The Taíno, the Guanahatabey and the Ciboney people; the ancestors of the Ciboney migrated from the mainland of South America, with the earliest sites dated to 5,000 BP. The Taíno arrived from Hispanola sometime in the 3rd century A. D; when Columbus arrived they were the dominant culture in Cuba, having an estimated population of 150,000. The Taíno were farmers, while the Ciboney were farmers as well as hunter-gatherers. After first landing on an island called Guanahani, Bahamas, on 12 October 1492, Christopher Columbus commanded his three ships: La Pinta, La Niña and the Santa María, to land on Cuba's northeastern coast on 28 October 1492. Columbus claimed the island for the new Kingdom of Spain and named it Isla Juana after Juan, Prince of Asturias. In 1511, the first Spanish settlement was founded by Diego Velázquez de Cuéllar at Baracoa. Other towns soon followed, including San Cristobal de la Habana, founded in 1515, which became the capital.
The native Taíno were forced to work under the encomienda system, which resembled a feudal system in Medieval Europe. Within a century the indigenous people were wiped out due to multiple factors Eurasian infectious diseases, to which they had no natural resistance, aggravated by harsh conditions of the repressive colonial subjugation. In 1529, a measles outbreak in Cuba killed two-thirds of those few natives who had survived smallpox. On 18 May 1539, Conquistador Hernando de Soto departed from Havana at the head of some 600 followers into a vast expedition through the Southeastern United States, starting at La Florida, in search of gold, treasure and power. On 1 September 1548, Dr. Gonzalo Perez de Angulo was appointed governor of Cuba, he arrived in Santiago, Cuba on 4 November 1549 and declared the liberty of all natives. He became Cuba's first permanent governor to reside in Havana instead of Santiago, he built Havana's first church made of maso
In the fields of horticulture and botany, the term deciduous means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves in the autumn. The term deciduous means "the dropping of a part, no longer needed" and the "falling away after its purpose is finished". In plants, it is the result of natural processes. "Deciduous" has a similar meaning when referring to animal parts, such as deciduous antlers in deer, deciduous teeth in some mammals. Wood from deciduous trees is used in a variety of ways in several industries including lumber for furniture and flooring, bowling pins and baseball bats and furniture, cabinets and paneling. In botany and horticulture, deciduous plants, including trees and herbaceous perennials, are those that lose all of their leaves for part of the year; this process is called abscission. In some cases leaf loss coincides with winter -- namely in polar climates. In other parts of the world, including tropical and arid regions, plants lose their leaves during the dry season or other seasons, depending on variations in rainfall.
The converse of deciduous is evergreen, where foliage is shed on a different schedule from deciduous trees, therefore appearing to remain green year round. Plants that are intermediate may be called semi-deciduous. Other plants are semi-evergreen and lose their leaves before the next growing season, retaining some during winter or dry periods; some trees, including a few species of oak, have desiccated leaves that remain on the tree through winter. Many deciduous plants flower during the period when they are leafless, as this increases the effectiveness of pollination; the absence of leaves improves wind transmission of pollen for wind-pollinated plants and increases the visibility of the flowers to insects in insect-pollinated plants. This strategy is not without risks, as the flowers can be damaged by frost or, in dry season regions, result in water stress on the plant. There is much less branch and trunk breakage from glaze ice storms when leafless, plants can reduce water loss due to the reduction in availability of liquid water during cold winter days.
Leaf drop or abscission involves complex physiological changes within plants. The process of photosynthesis degrades the supply of chlorophylls in foliage; when autumn arrives and the days are shorter or when plants are drought-stressed, deciduous trees decrease chlorophyll pigment production, allowing other pigments present in the leaf to become apparent, resulting in non-green colored foliage. The brightest leaf colors are produced when days grow short and nights are cool, but remain above freezing; these other pigments include carotenoids that are yellow and orange. Anthocyanin pigments produce red and purple colors, though they are not always present in the leaves. Rather, they are produced in the foliage in late summer, when sugars are trapped in the leaves after the process of abscission begins. Parts of the world that have showy displays of bright autumn colors are limited to locations where days become short and nights are cool. In other parts of the world, the leaves of deciduous trees fall off without turning the bright colors produced from the accumulation of anthocyanin pigments.
The beginnings of leaf drop starts when an abscission layer is formed between the leaf petiole and the stem. This layer is formed in the spring during active new growth of the leaf; the cells are sensitive to a plant hormone called auxin, produced by the leaf and other parts of the plant. When auxin coming from the leaf is produced at a rate consistent with that from the body of the plant, the cells of the abscission layer remain connected; the elongation of these cells break the connection between the different cell layers, allowing the leaf to break away from the plant. It forms a layer that seals the break, so the plant does not lose sap. A number of deciduous plants remove nitrogen and carbon from the foliage before they are shed and store them in the form of proteins in the vacuoles of parenchyma cells in the roots and the inner bark. In the spring, these proteins are used as a nitrogen source during the growth of new leaves or flowers. Plants with deciduous foliage have advantages and disadvantages compared to plants with evergreen foliage.
Since deciduous plants lose their leaves to conserve water or to better survive winter weather conditions, they must regrow new foliage during the next suitable growing season. Evergreens suffer greater water loss during the winter and they can experience greater predation pressure when small. Losing leaves in winter may reduce damage from insects. Removing leaves reduces cavitation which can damage xylem vessels in plants; this allows deciduous plants to have xylem vessels with larger diameters and therefore a greater rate of transpiration during the summer growth period