B amboos include over 1,000 species of woody, perennial grasses in more than 100 genera. Most botanists place them in the tribe Bambuseae within the grass family Poaceae, a large family of 10,000 species and at least 600 genera. Grasses range in size from small annuals (Poa annua) to towering, timber bamboo (Dendrocalamus giganteus). This is unquestionably the most important plant family, providing the majority of food for humans and their domesticated animals. The grasses are relatively recent additions to the earth's flora, having evolved only 30 to 40 million years ago, long after the demise of the dinosaurs. Vast grasslands provided food for the rising age of herbivorous mammals which in turn provided the food for a variety of carnivores. Some plants called "bamboo" are not grasses. The popular, indoor "lucky bamboo" grown hydroponically in vases of water is actually Draceana sanderana, a member of the lily family (Liliaceae). It is also placed in the agave family (Agavaceae) and dracena family (Dracenaceae) by some botanists. Heavenly bamboo (Nandina domestica) is a cultivated dicotyledonous shrub in the barberry family (Berberidaceae). Left: The range of sizes in the grass family (Poaceae) is enormous. Here is a small individual of annual bluegrass (Poa annua) compared with a U.S. penny (one cent). Right: Young, tender shoots sprouting from stems cuttings of "lucky bamboo" Draceana sanderana, a popular indoor plant that belongs to the lily family (Liliaceae). Unlike the hollow internodes of true bamboos, the stems of this plant are composed of solid parenchyma tissue. B amboos are widespread throughout the Old and New World tropics, with one species (Arundinaria gigantea) native to the United States. In California, the naturalized giant reed (Arundo donax) is often referred to as a bamboo, but is usually classified in the arundo tribe (Arundineae) along with common reed (Phragmites australis) and pampas grass (Cortaderia). Sugar cane (Saccharum officinarum), a large, woody grass with C-4 photosynthesis, belongs to the andropogon tribe (Andropogoneae) along with corn (Zea mays) and Job's tears (Coix lacryma-jobi). Another large grass called wild cane (Saccharum spontaneum) is naturalized in the Hawaiian Islands. Unlike members of the andropogon tribe with C-4 photosynthesis, all species of the bamboo tribe (Bambuseae) and arundo tribe have C-3 photosynthesis (Walters and Keil, 1996). The bamboo-like stems of sugar cane (Saccharum officinarum) are rich in table sugar (sucrose). Raw sugar is brown in color. The thick, brown, sugary syrup produced during the separation of sugar crystals from the ground-up cane is called molasses. C-4 Photosynthesis In Sugar Cane During C-4 photosynthesis, CO 2 combines with phosphoenolpyruvate (PEP) to form a 4-carbon organic acid (oxaloacetic acid) which migrates (diffuses) to the photosynthetic bundle sheath cells surrounding the vascular bundles (veins) of the leaf. PEP essentially shuttles the CO 2 to the bundle sheath cells where it is released for the dark reactions (Calvin cycle) of photosynthesis. During hot weather the CO 2 level inside leaves is greatly reduced because the leaf stomata are closed. In ordinary C-3 plants which form a 3-carbon compound (PGA) during the initial steps of the dark reactions, photosynthesis in the leaf shuts down without a sufficient supply of CO 2 . C-4 plants have a competitive advantage during hot summer days because they are able to carry on photosynthesis in the bundle sheaths where CO 2 levels are concentrated. C-4 grasses include Bermuda grass (Cynodon dactylon), crabgrass (Digitaria sanguinalis), sugar cane (Saccharum officinarum), corn (Zea mays) and sorghum (Sorghum bicolor). C-4 grasses and weedy herbs, such as purslane (Portulaca oleracea) and prostrate ground spurges (Chamaecyse), grow rapidly during hot summer days when photosynthesis and growth in C-3 plants shuts down. Job's Tears & Ancestry Of Corn (Maize)

Clumping Bamboo Splitting A Sewer Pipe

Sugar Cane Crop In The Hawaiian Islands

Genetics and Structure Of Cereal Grasses

C-4 Photosynthesis In Purslane (Portulaca) B amboos typically form dense, impenetrable clumps or spread by creeping rhizomes. Clumping bamboos are mostly native to tropical contries, such as Indonesia, Burma, Brazil, Colombia, Ecuador, India, Thailand and southern China. A few "mountain bamboos" from the Himalayas and the Andes are "temperate clumpers" that can survive in areas with freezing winters. Running bamboos are mostly from temperate climates of Japan, northern China, Siberia and one native species in the United States. Bamboos range in size from low, shrubby forms only ten feet (3 m) tall to towering giants over 100 feet (30 m). Aerial stems (called culms) develop from scaly, underground stems called rhizomes that bear roots at the nodes where the leaflike scales are attached. Giant reed (Arundo donax), a tall, bamboo-like grass that is naturalized throughout San Diego County. Like certain bamboos, it spreads by underground rhizomes and has many uses by people throughout the world. C lumping bamboos, such as the large genus Bambusa, develop from branched clusters of short, "pachymorph" rhizomes that turn upward as soon as they are formed, each rhizome developing into a new culm close to the parent plant. Running bamboos, such as the genus Phyllostachys, develop from long, slender, "leptomorph" rhizomes that grow horizontally under the soil. These bamboos send up aerial culms from buds that develop at intervals along the rhizome, behind the continually growing rhizome tip. Rhizomes of running bamboos can grow more than thirty feet in one year. Entire hillsides of this type of bamboo can develop asexually from a single ancestral rhizome. In fact, the dense forests of Phyllostachys nigra in the rain forest of east Maui represent massive clonal colonies. This Chinese species was first collected on the island of Oahu in 1951. Left: Extensive forest of black bamboo (Phyllostachys nigra) along the road to Hana on the rain-soaked east coast of Maui. Right: Close-up view of the striking culms of black bamboo. Populations of this species on the Hawaiian Islands have uniformly green culms and are referred to as var. henionis. Running "leptomorph" rhizome of black bamboo (Phyllostachys nigra). This type of rhizome grows horizontally under the soil, sending up aerial culms from buds that develop at intervals along the rhizome, behind the continually growing rhizome tip. With plenty of moisture, running bamboos can form massive clonal colonies covering entire hillsides. L ike most other grasses, bamboos grow and flourish until they are ready to flower; then they produce seeds and die. Because bamboos flower so infrequently, they are usually propagated vegetatively. Running bamboos are usually propagated by cuttings of the rhizome, with some buds and culms attached. Clumping bamboos can be propagated by taking a piece of a culm with at least one node and planting it in damp soil. The cut stem will develop roots at the node and produce new rhizomes and culms. Therefore, most varieties of bamboos in cultivation are clones derived from a single plant that may be traced back to one seed. This may explain why some cultivated bamboos have the same flowering cycle and mortality as populations on different continents. It should be noted here that the majority of bamboo species are not monocarpic, i.e. they do not flower gregariously and then die. A scaly, underground rhizome of giant reed (Arundo donax), a bamboo relative in the tribe Arundineae. Three developing upright stems are shown by the red arrows. The terminal end of the rhizome is upcurved into a developing culm. The thickened, upturned rhizome tip is typical of a clumping bamboos; however, this rhizome can also spread horizontally with multiple buds developing into upright culms. This species has become an aggressive, naturalized weed in riparian habitats of southern California. A erial culms of bamboo are hollow except at the nodes where lateral buds and leafy branches develop. Monocot stems, such as bamboo and palms, do not have a vascular cambium and do not exhibit secondary growth by the production of concentric annual rings. They cannot increase in girth by adding lateral layers of cells as in conifers and woody dicots. Instead, they have scattered vascular bundles composed of xylem and phloem tissue, each bundle surrounded by a ring of cells called a bundle sheath. The maximum diameter of bamboo stems is predetermined at the time of sprouting (see below). Unlike bamboo and most monocots, palm stems can grow in girth by an increase in the number of parenchyma cells and vascular bundles. This primary growth is due to a region of actively dividing meristematic cells called the primary thickening meristem that surrounds the apical meristem at the tip of a stem. Dried, packaged leaves sold as bamboo in Asian Markets. The leaves are used for wrapping glutinous rice dumplings called "zongzi" eaten during the Dragon Boat Festival on day five of the fifth lunar month. Bamboo leaves are also used for lining the bottoms of pans when cooking rice cakes, meat patties and other dishes. Although the stem in the above image is a bamboo, the leaves typically come from a tall, naturalized grass called "kong" or "tiger grass" (Thysanolaena maxima). Stem & Root Anatomy Of Vascular Plants T he structural strength and hardness of bamboo stems is due to masses of heavily lignified tracheids and fibers associated with the vascular bundles. The wood (xylem) of conifers and dicot trees is composed of concentric layers of dense, lignified cells containing cellulose and lignin in their secondary walls. In addition to cellulose and lignin, the thick-walled fibers of bamboo also contain up to five percent silica in the form of silicon dioxide (SiO 2 ). Although bamboo culms do not have the structure of true wood, they are very hard because they contain silica and lignin. A beautiful cutting board made from numerous flattened strips of bamboo (Phyllostachys pubescens) glued together. Through a specialized heating process, the natural sugar in the wood is caramelized to produce the honey color. Vascular bundles typical of a woody monocut are clearly visible on the smooth cross section. The transverse surface of numerous lignified tracheids and fibers is actually harder than maple. Cutting board available from Totally Bamboo website: www.totallybamboo.com A s stated above, the diameter of a bamboo stem is essentially determined at the time of sprouting. The actual diameter depends on the exact species of bamboo. Just below the growing point (apical meristem) is an active region of cell division and differentiation that is responsible for the predetermined size of bamboo shoots. When a bamboo shoot emerges from the soil it consists of a series of tightly overlapping protective sheaths surrounding the developing nodes and internodes (each sheath enveloping the culm and internodes above it). The culm sheath terminates in a leaf blade that typically extends away from the culm. In bamboo shoots, the greatly reduced leaf blade is represented by a small, pointed protrusion of the sheath. Between the sheath and blade, many species have a scalelike ligule and earlike projections called auricles. The ligule and auricles may be fringed with minute bristles. All the leaf-bearing nodes are predetermined in the shoot, which grows out telescopically as the internodes elongate. This is similar to the extension of the legs of a camera tripod or the sliding tubes of a collapsible telescope or radio antenna. Longitudinal view of a tender, edible bamboo shoot (Bambusa species). The shoot emerges from the ground at its maximum thickness with the nodes, internodes and overlapping sheaths already formed. The apical meristem gives rise to distinct sections or bands. As the cells within these sections divide, differentiate and elongate, the internodes extend out from each other like the sliding tubes of an expanding telescope. I f a bamboo shoot is cut off before it has begun to elongate, the culm dies. If it is cut after the culm has started to develop and elongate, it will branch out from the nodes and produce new foliage. Herbaceous grasses, such as cultivated cereals and naturalized weeds, continue to grow even after mowing. This is explained in the following section. Note: In herbaceous (nonwoody) grasses, such as wheat, rice, barley and oats, each sheath envelops the culm down to its point of origin at the node. At the upper end of each culm sheath is the leaf blade, which typically extends away from the culm. At the junction of the sheath and blade is a small, membranous scale called the ligule. Minute projections at the base of the leaf blade are called auricles. Grass leaves grow from an intercalary meristem at the base of the sheath in the node region. This is why the tranversely cut blades of your lawn grow upward even though you mowed them off the previous week. The meristematic region of herbaceous annual and perennial grasses is at the base of the leaves and continually produces more leaf tissue. This is undoubtedly an adaptation to grazing animals which could destroy the grass plant if the vulnerable growth regions were apical rather than basal. Flowering (seed-bearing) stems of cereal grasses develop from apical meristems that generally do not resprout if the peduncle (flower stalk) is severed. Annual grasses (including many weedy grasses in San Diego County) die following their blooming cycle. Perennial grases die back to the rhizome and resprout the following year. Annual blugrass (Poa annua), a common naturalized weed in southern California. The leaf blade extends down the culm as an enveloping sheath to a slightly enlarged point of attachment on the culm called the node. At the junction of the leaf blade and culm sheath is a small scalelike ligule. The floret consists of two bracts called the palea and lemma. Within the floret is the apetalous, bisexual grass flower consisting of a gynoecium (pistil) and three stamens (androecium). Following pollination and fertilization, the ovary develops into a one-seeded fruit called a grain or caryopsis. In some grasses, the minute remnants of perianth segments called lodicules are visible at the base of the ovary. Grasses are typically wind-pollinated, although some species have cleistogamous, self-pollinated flowers that remain closed within the bracts of the floret. The tender sprouts of several bamboo genera are often eaten as a vegetable, including Phyllostachys, Bambusa and Sasa. Tasty bambo shoots are common ingredients in many delicious Asian dishes. B amboos are very important plants, both ecologically and economically. They are one of the most useful and valuable plants for people and provide the primary diet for giant pandas. Giant pandas are indigenous to mountain forests of small, cold-tolerant bamboos in the Yunnan province of southern China. Although they have a carnivorous ancestry and are members of the bear family (Ursidae), giant pandas have evolved a vegetarian diet of bamboos and eat the entire shoots, leaves and stems. The Himalayan red panda also feeds on bamboos along with a variety of other plants. It belongs to the family Procyonidae along with American racoons, coatimundis and ringtails. Left: Buddha's belly bamboo (Bambusa ventricosa = B. tuldoides cv. 'ventricosa'). This species is named for the swollen internodes that often develop when it is grown in tight, root-bound containers. Right: Painted bamboo (B. vulgaris cv. 'vittata' = B. vulgaris cv. 'striata') The striking culms of yellow groove bamboo (Phyllostachys aureosulcata) have a prominent groove or sulcus along one side of each internode. This groove is characteristic of species within the genus Phyllostachys. G iant pandas are completely dependent on bamboo for food, and they require enormous quantities of it. Because of a rather inefficient digestive system compared with other herbivores, giant pandas may consume up to 85 pounds (38 kg) of bamboo per day. Pandas digest about twenty percent of the bamboo they consume, while cattle can digest sixty percent of their intake. Pandas will eat other species of bamboo but apparently prefer the kinds that grow wild in their native habitat, including Himalayacalamus, Fargesia, Drepanostachyum and Sinarundinaria, all native to Yunnan, Tibet, Nepal and northern India. Pandas once roamed over a wide range in southern China. Before the fertile valleys became farmland, they could move from one area to another to find a variety of bamboos. Now they are restricted to isolated mountain regions in which there are relatively few species of bamboo. This habitat isolation is a potentially serious problem when bamboo species that giant pandas depend on suddenly flower and die. S ome bamboo species bloom simultaneously and then die, a phenomenon that is still under investigation by plant physiologists. These species produce seed once in their life cycle and are termed monocarpic. Like other biological phenomena, there are exceptions to this worldwide mortality. In fact, most species of bamboo are not monocarpic. Some bamboos observed in cultivation are greatly weakened or die back following the blooming cycle, but actually recover in a few years and may even live to bloom again. With an average human life cycle of perhaps eighty years, few mortal botanists have ever followed the life cycle of a particular bamboo plant from germination to flowering! Variations in the exact flowering period for a given species have also been observed in cultivated bamboos. When cultivated bamboo species bloom precisely at the same time, they are very likely clones from an original rhizome that has been propagated vegetatively. Depending on the species, the unusual delayed blooming cycle may occur only once in a century. Even more astonishing is the fact that over huge geographic areas all the bamboo of a single species may flower and fruit at the same time, resulting in enormous grain (seed) production and widespread die-offs. When this massive die-off was observed in a panda preserve in 1983 the panda inhabitants faced starvation, while pandas on different mountains (with different bamboo species) had sufficient food. The Chinese launched a campaign to relocate about ten percent of the pandas in zoos; however, their failure to reproduce well in captivity further exacerbated the decline in panda populations. The birth of Hua Mei at the San Diego Zoo in the 1999 using artificial insemination was indeed a triumph for the panda breeding program. Close-up view of the inflorescence of yellow-groove bamboo (Phyllostachys aureosulcata), a species easily identified by a yellow groove (sulcus) along one side of each internode. The inflorescences (panicles) develop at the tips of the stems where new leaves are typically produced. Unlike most grasses, the floret-bearing spikelets are enclosed in deciduous sheathlike bracts. In fact, the generic name Phyllostachys is derived from the Greek "phyllos" (leaf) and "stachys" (spike), referring to the apical, sheathlike bracts covering the spikelets. The inflorescence was collected in the Palomar College Arboretum on 21 July 2002. Right: Magnified view of the flower (floret) of yellow-groove bamboo (Phyllostachys aureosulcata), consisting of minute papery bracts (lemma and palea) which enclose an ovule-bearing ovary and three stamens. The anthers are on long stalks (filaments) that hang out of the floret. Like other grasses, bamboos are wind pollinated. After pollination the ovary develops into a one-seeded fruit called a grain or caryopsis. Numerous floret-bearing spikelets are produced in a branched inflorescence at the tips of branches. One or more spikelets are enclosed by deciduous sheathlike bracts. The inflorescence was collected in the Palomar College Arboretum on 21 July 2002. A spikelet of yellow-groove bamboo (Phyllostachys aureosulcata). Each spikelet consists of 3 to 6 florets. Several stamens and a feathery stigma are protruding from the upper pair of fertile florets. A single fertile floret (flower) of yellow-groove bamboo (Phyllostachys aureosulcata). Each floret is contained within two bracts called the lemma and palea. The two fertile florets occur in a spikelet composed of 3-6 florets subtended by a pair of glumes. Grasses are typically wind-pollinated and have no need for showy petals like other flowering plants. S everal hypotheses have been proposed to explain the ecological advantage of producing seed-bearing fruit only once in a life cycle (monocarpic) and with a long time interval between germination and death of up to 120 years. As I stated above, this phenomemon does not apply to the majority of bamboo species. One of the most plausible explanations involves a clever strategy to avoid annual seed predation by rodents, such as rats. Rodents are very fond of bamboo grains and if the seed predators were in tune with bamboo flowering and fruiting, they could easily destroy the bulk of the seed crop each year. With massive fruiting only once or twice in a century, the bamboos avoid tracking by vertebrates whose generation time is much shorter than the flowering cycle. With abundant food, the rodent population could increase substantially during the year following the bamboo flowering cycle; but for the next 30 to 60 years (or more), the rodent population would decrease and stabilize again while the bamboo populations regenerate. This strategy to avoid seed predation, and the extensive cultivation of fertile valleys between mountainous regions, has seriously threatened the panda populations in southern China. B amboos are very useful plants throughout the Old and New World tropics. It has been estimated that they are used by more than half of the world's human population every day. According to A. Lewington (Plants For People, 1990), more than 1000 different products are made from bamboo. Bamboo shoots are edible and are a major component of Asian dishes. Since fresh shoots are more flavorful than canned, bamboo farms have been established in the United States. In Tanzania, "bamboo wine" is made from the fermented juice of the wine bamboo (Oxytenanthera braunii). Although bamboo shoots are tender and weak, they grow very rapidly. In fact, there are records of tropical bamboos growing 100 feet in three months, an astonishing 0.0002 miles per hour! When the shoots leaf out in sunlight they become very strong and woody (lignified). Some bamboos stems have the same tensile strength as certain types of steel and are used to reinforce concrete. After about ten years the stems begin to deteriorate in humid tropical regions. Bamboo canes are used to make cooking utensils, blow guns, toys and furniture. Bamboo pulp is used to make paper, and small, polished stem segments are sometimes used in necklaces. Polished bamboo culm sections from a species of Phyllostachys. The hollow sections are strung into attractive necklaces. How About A Mountain Bike Frame Made Of Bamboo! T he wooden sword called a "shinai" used in the Japanese martial art of kendo is made from longitudinal strips of strong bamboo culms. Several strips are tightly bound together with string. There are many weapons made from bamboo, including bows and arrows and sharpened bamboo stakes. In Sumatra, native hunters fashion blowguns (blowpipes) from bamboo culms to shoot deadly poison darts. Strong swords made from bamboo culms

are used in the ancient Japanese martial

art of kendo. The objective is to score

points by striking your opponent's head,

arms and torso in strategic places. The

opponents wear heavy, protective armor. See Animated Kendo Image A long with palms, bamboos are one of the world's most important building materials, particularly in areas where timber trees are in short supply. Large timber bamboos, including Dendrocalamus giganteus and Bambusa oldhamii are used for scaffolding, bridge-building, water pipes, storage vessels and to build houses. In fact, as a building material bamboo plays an important role in almost every country in which it occurs. In Burma and Bangladesh, about fifty percent of the houses are made almost entirely of bamboo. In Java, woven bamboo mats and screens are commonly used in timber house frames. With modern polymer glues and bonding cements, bamboos are made into plywood, matboard and laminated beams. Left: Giant timber bamboo (Dendrocalamus giganteus), one of the largest species of bamboo. Right: Running bamboo (Phyllostachys vivax), a fast-growing species that spreads by horizontal, multi-culmed rhizomes. Thatching From The Bayleaf Palm Of Belize F or centuries, Marsh Arabs of Iraq have constructed their houses entirely from bamboo-like grasses called reeds, including Phragmites australis and Arundo donax. The name Canebrake Canyon in San Diego County is derived from the common reed (Phragmites australis). This native grass may be the most widely distributed of all vascular seed plants. Where wood is scarce, bundles of reeds are used for various mud constructions, such as arches. Long after the reeds have rotted away, the arch made of layers of baked mud, still stands. One of the oldest arches in the history of architecture at Gesiphon near the site of the ancient city of Babylon is still standing, its baked bricks are more than 2,000 years old. Common reed (Phragmites australis) in a large marsh near Shoshone, California (Death Valley region). In addition to numerous uses by native Americans, this native grass also provides a refuge for wildlife. It is considered by some botanists to be the most widely distributed of all vascular seed plants. B amboo has been a major building material for boats in China for countless centuries. In fact, the sectioned culms which divide the stem internodes into separate compartments may have given early boat-builders the idea of making water-tight bulkheads. Many of the junks, sampans and rafts that navigate the vast waterways of China are constructed partly or entirely of bamboo. Grass-like members of the sedge family (Cyperaceae) have also been used to make sea-worthy boats, including papyrus (Cyperus papyrus) and bulrushes of the genus Schoenoplectus. For centuries Oru Indians of Lake Titicaca in Bolivia have made boats from totora reeds (Schoenoplectus tatora). Four long bundles of reeds which taper at both ends are firmly bound together with strong ichu grass (Stipa ichu). Even the sails are made of from totora reeds which have been split and sewn together lengthwise. In his book, Sea Routes to Polynesia (1968), Thor Heyerdahl postulated that sweet potatoes were carried across the Pacific by Peruvian Indians before Europeans began to sail the world's oceans. He tested his hypothesis in 1947 by sailing a balsa wood raft, the Kon-Tiki, fashioned after the reed rafts of the Oru Indians living on Lake Titicaca in Bolivia. Although Heyerdahl's hypothesis about the transoceanic exchange of sweet potatoes by skillful pre-Columbian sailors remains an enigma (at least to some skeptics), his New World origin for the coconut has been rejected by most botanists. See The New World Of Origin Of Coconut Palms R eeds and bamboos are very significant plants in the development and evolution of musical wind instruments. The variety of flutes and panpipes used by Andean musicians of Peru, Bolivia and Ecuador are made from native bamboo species, including the genus Chusquea and the pantropical reed Arundo donax. Different lengths and widths of the hollow culms produce the light airy sounds of small sikus or zampoñas and the deep bass notes of Bolivian toyos. Some of the world's most beautiful music is produced by these relatively crude instruments. Panpipes have also been made in France and the Balkan countries, primarily from the reed Arudo donax collected in marshlands of the Danube delta. A panpipe from South America and a bamboo flute from India. T he best "reeds" for clarinet and oboe mouthpieces also come from Arundo donax. This grass is naturalized throughout the world, including river valleys and creeks of San Diego County. Often called giant reed, it spreads by thick scaly rhizomes, forming impenetrable thickets of bamboo-like stems. In fact, giant reed can literally overtake other native species in riparian habitats and is considered one of the most serious weeds in California. According to W.W. Robbins, et al. (Weeds of California, 1941), giant reed was so plentiful along the Los Angeles River in the early 1800s that it was gathered for roofing material and was preferred over the native tules (Scirpus californicus). Because of its invasiveness, drastic control measures have been used in San Diego County, including burning and herbicide sprays. A clarinet mouthpiece and "reeds" from the giant reed (Arundo donax). B amboos have also been used for wind instruments in Asian countries. The national instrument of Japan, the shaku hachi, is made from the lower end of small-culmed bamboos. The Chinese xiao, a notched flute played in modern orchestras, is made from the bamboo Phyllostachys nigra. In the Philippine city of Las Piñas, each of the 950 pipes of a remarkable organ is made from hollow bamboo culms; in Java, more than twenty percussion, wind and string instruments are made from bamboos, mostly from the genus Gigantochloa; and in Bali, the fungklih xylophone has keys made from bamboo.