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A. General Fruit Terminology

Carpel:Leaf-like megasporophyll bearing one or more ovules on the inner surface. In dehiscent dry fruits that split open, carpels are represented by the seed-bearing sections. Carpels are difficult to distinguish in dry, indehiscent fruits (e.g. nuts) and fleshy fruits (e.g. berries). Carpels are the innermost parts of a complete flower and they are united to form the gynoecium (pistil).

B. Dehiscent Dry Fruits (Split Open At Maturity)1. Legume or Pod:Composed of one carpel.Note: Some legumes are indehiscent and do not split open.

A legume (such as a bean pod) is composed a one folded carpel. It splits lengthwise along two seams into two sections, each of which represents half of a carpel. Some legume pods, such as carob and mesquite, are indehiscent and do not split open.

The peanut (Arachis hypogea) is a dehiscent legume that is harvested from below the soil. The legume was originally formed above ground following pollination. After fertilization, the flower stalk of the peanut curves downward, and the developing pod is forced into the ground by the proliferation and elongation of cells under the ovary. The pod typically contains two seeds, each with a papery seed coat. Peanut seeds are eaten raw, salted and roasted. Peanuts are ground into peanut butter and Thai peanut sauce, and the expressed oil is used in cooking. Peanuts are also used in cookies, peanut brittle and candy bars.

See Indehiscent Pods Of Carob TreeA Peanut Plant With Subterranean PodAssorted Legumes Used For Vegetables

Note:Some legume fruits are indehiscent, including the carob tree, mesquite and honey locust. In addition, some legume fruits are oblong, rounded, kidney-shaped (reniform), or coiled (spiral-shaped), such as sweet clover (Melilotus albaandM. officinalis), black medic (Medicago lupulina), bur clover (M. polymorpha) and alfalfa (M. sativa). Some specialized legume fruits (called loments) break apart into indehiscent, seed-bearing segments. A good example of a loment is the fruit of crown vetch (Coronilla varia), a European wildflower that is naturalized throughout parts of North America. The slender pods are constricted between the seed-bearing segments.

Crown vetch (Coronilla varia) from Palomar Mountain in San Diego County, California. Note the slender legume fruit (called a loment) with constrictions between the seed-bearing segments. The fruit breaks apart transversely into seed-bearing sections. This attractive European wildflower has become a troublesome weed in parts of North America. It has been planted on road cuts for erosion control, but is a very invasive perennial with creeping rhizomes and prolific seed production.

Stick-tights or beggar's-ticks (Desmodium cuspidatum) produces slender loments that break into small, one-seeded joints covered with tiny barbed hairs. The individual joints are so flat that they are exceedingly difficult to remove from your socks. Like little flat ticks, you must individually pull off each one. This can be exasperating when your socks are covered with them. Several species of this remarkable hitchhiking herb are native to the midwestern and eastern United States.

The Wayne's Word Top 17 Hitchkiking PlantsThe Classification Of Major Types Of Fruits

2. Capsule:Composed of several fused carpels.

The separate carpels of a true capsule were originally fused together to form the pistil or gynoecium. They separate along the septa or along the locules between septa.

Four methods of dehiscence in capsules: The carpels may separate along the septa or along the locules between the septa. Some capsules dehisce by a lid that falls off exposing the seeds. Poppies of the genusPapaver, including the opium poppy (P. somniferum), dehisce by small apical pores near the top of the capsule. As the capsule moves back and forth in the wind, the seeds are released like a pepper shaker.

Capsule Cluster Of Liquidambar TreeSee Circumscissile Capsule Of PurslaneSee Exploding Capsules Of Witch HazelSee Article About Mexican Jumping BeansDevil's Claws: Amazing Hitchhiking CapsulesOpium Poppy Capsule: Source Of Raw Opium

It sould be noted here that some capsules are indehiscent. Their carpels do not separate and release the seeds. Two examples of plants with indehiscent capsules are the South African baobab tree (Adansonia digitata) and two species of South African gardenias (Gardenia thunbergiiandG. volkensii). The seed pods of South African gardenias are chewed opened by large herbivores, and the seeds are dispersed in their feces.

Indehiscent capsule of the baobab tree (Adansonia digitata). Left: A dry fruit showing the velvety outer exocarp. Right: Longitudinal section of a dry fruit showing the large, angular seeds. Each seed is embedded in a white pulp which has a pleasant tart flavor. The lower left seed has been removed from the pulp. The common names of "cream-of-tarter tree" and "lemonade tree" are derivied from the powdered pulp which is mixed which water to make a refreshing drink. Baboons tear open the fruits to eat this tasty pulp.

Indehiscent Capsules of South African GardeniasSee Photo Of A South African Baobab Tree

3. Follicle:One carpel that splits along one seam.

The single carpel of a follicle splits open along one seam. When completely opened, the carpel resembles a thick, dried leaf. It is easy to see that the single carpel of a follicle is a modified, seed-bearing leaf (megasporophyll).

Parachute Seeds Of The MilkweedFollicles Of Scarlet Larkspur & PeonyFollicle Of The Indian Almond (Sterculia)Follicles Of The Primitive Magnolia Family

4. Silique:Two carpels separated by a seed-bearing septum.

The silique is an elongate fruit composed of two carpels separated by a seed-bearing partition. The silicle is very similar except it is much shorter (less than twice as long as broad). Siliques and silicles have parietal placentation. They are the characteristic fruits of the mustard family (Brassicaceae). Some members of the mustard family have siliques that do not split longitudinally into two separate carpels. For example, fruits of the radish (Raphanus sativus) split transversely into seed-bearing sections (joints).

The overlapping seeds of bitter cress (Cardamine) are connected to alternate edges of the septum within each locule. The minute seeds are attached to both margins of the central septum. This revelation requires the skillful use of a dissecting microscope. In theJepson Flora of California(1993), this genus keys out under "one row of seeds in each locule," without mentioning the alternating seed attachments along both edges of the septum. Apparently, the superficial appearance of the overlapping seeds in a single file is the defining character for the key.

A species of bitter cress (Cardamine) collected along the damp seepage area of a lawn in northern San Diego County. It is an annual with a fibrous root system (without rhizomes). The leafy stems are erect or ascending (curving upward from the base). The leaves are odd pinnate with 2 or three pairs of leaflets. This species of bitter cress greatly resembles the European annualC. flexuosaWith. Another native species reported for San Diego County (C. oligospermaTorrey & A. Gray) has similar compound leaves; however, it has a distinct basal leaf rosette that is lacking in this species. It is interesting to note thatC. flexuosaWith. has now been added to the San Diego Natural History Museum on-lineChecklist of Vascular Plants of San Diego County.

The seeds of water cress (Rorippa nasturtium-aquaticum) are connected along both margins of the septum within each locule. In theJepson Flora of California(1993), this species keys out under "two rows of seeds in each locule." AlthoughCardaminealso has seeds attached in two rows, the seeds are overlapping and do not appear distinctly 2-ranked. InRorippathe seeds appear more distinctly two-ranked, and this is apparently a defining character for the key.

Inflorescence (raceme) of shepherd's-purse (Capsella bursa-pastoris), a common European annual that is naturalized in southern California. The silicles are inverted heart-shaped (obcordate). The membranous partitions remain on the pedicels long after the valves of the silicles have fallen away.

Moonwort (Lunaria annua), a European annual or biennial naturalized in California. The fruits of this species are called silicles because they are broad compared with the elongate and slender siliques. Generally silicles are only twice as long as broad (or less). The septum of each silicle remains attached to the dried flower stalk, long after the valves and seeds have fallen away.

C. Indehiscent Dry Fruits (Do Not Split Open At Maturity)1. Achene:Small, one-seeded fruit; pericarp free from seed coat.Note: In the grain or caryopsis, the pericarp is fused with the seed coat.

The achene is the typical fruit of the sunflower family (Asteraceae). It is a small, one-seeded fruit containing a single seed. The seed is attached by a funiculus, but the seed coat is free from the inner wall of the pericarp.

Achenes of the sunflower (Helianthus annuus). One achene has been sectioned to reveal the single seed inside. The seed is essentially free within the pericarp wall, except where it is attached at the placenta. Sunflower seeds of this variety with striped pericarps is used primarily for food. Seeds from achenes with solid black pericarps are used for sunflower oil.

One-seeded achenes of buckwheat (Fagopyrum esculentum), an important crop plant native to central Asia. The three-sided achenes resemble miniature nuts from the beech tree (Fagus). This resemblance led to the German name "buchweizen" (beech-wheat) which became corrupted to the present name of buckwheat. The hulled achenes or groats are used in several brands of hot and cold breakfast cereals. The seeds are ground into flour which is used for pancakes, noodles and breads. In Russia, a nutritious porridge called "kasha" is made from buckwheat flour.

Two angular nuts of American beech (Fagus grandifolia) within a spiny involucre. The three-sided nuts resemble the miniature one-seeded achenes of buckwheat (Fagopyrum esculentum). This resemblance led to the German name "buchweizen" (beech-wheat) which became corrupted to the present name of buckwheat.

See Minute Achenes Of Dwarf FluffweedSee Achenes Of The Buckwheat FamilySee Achenes Of The Sunflower FamilySee Parachute Achenes Of Dandelions

2. Anthocarp:Small, one-seeded fruit enclosed by a fused perianth or receptacle.In the four o'clock family (Nyctaginaceae), individual apetalous flowers have a tubular, petaloid calyx that resembles a sympetalous corolla. The lower portion of the calyx tightly enwraps the one-seeded achene and is persistent around the fruit as an anthocarp. The calyx base plus the enclosed seed-bearing achene is the unit of dispersal. In some members of the Nyctaginaceae, the persistent calyx base bears sticky glandular projections that aid in dispersal by adhering to the bodies of animals. This is especially true in pisonia trees (Pisonia umbellifera) in which the numerous glutinous anthocarps stick to the feathers of seabirds.

See Flowering Branch Of A Pisonia Tree

Two anthocarps of the desert sand verbena (Abronia villosavar.villosa). Eachseed-bearing ovary (achene) is tightly encased within the persistent winged calyx.

Left: Desert (dune) evening primrose (Oeothera deltoidesssp.deltoides). Right: Desert sand verbena (Abronia villosavar.villosa). Both species commonly occur together in sandy riverbeds of Anza-Borrego State Park, San Diego County.

Yellow sand verbena (Abronia latifolia) on the coastal dunes of Monterey County.

Yellow sand verbena (Abronia latifolia) on the coastal dunes of Monterey County.

Two anthocarps of (Boerhavia intermedia) attached to the sticky stem of this small desert annual. Each elongate (obpyramidal), seed-bearing anthocarp is truncate at the widest end (apex). The anthocarp has five longitudinal ribs and is wrinkled (transversely rugulose) between the ribs. The minute anthocarps were photographed by Tom Chester in Palm Canyon, Anza-Borrego State Park (November 2003).

3. Grain (Caryopsis):One-seeded fruit; pericarp fused with seed coat.

Rice (Oryza sativa).A.Grain-bearing spikelet showing a pair of slender basal bracts (glumes) and the stalk (pedicel). The inflorescence is composed of numerous spikelets, each bearing a rice grain.B.An empty spikelet with the lemma and palea slightly separated from each other. These two leathery bracts enclosed the grain or caryopsis.C.A grain (caryopsis) removed from spikelet (B). The embryo or germ is at upper end. Beneath the brownish outer pericarp and seed coat layers (called the bran) is the endosperm tissue. Most of the vitamin B1is found in the germ and bran portions, which are milled off in polished white rice.

Grains of brown and polished white rice. In polished white rice (left), most of the bran and germ has been milled away, resulting in an improved flavor (at least to some people). The grains appear slightly more slender, with the apical germ region ground off giving the grains a slightly pointed appearance (red arrow). In white rice you are eating mostly the carbohydrate-rich endosperm tissue which lacks the vitamin B1of the bran and germ. Even though it is less nutritious, white rice is still preferred by Asians, and is the most popular grain served in Chinese and Japanese restaurants in the United States.

Photos Of Cereal GrassesJob's Tears & Corn (Maize)Wind Dispersal Of Grasses (1)Wind Dispersal Of Grasses (2)Bamboo: Remarkable Giant Grass

4. Samara:One-seeded, winged achene.

The samara is a peculiar one-seeded fruit similar to an achene except the pericarp wall extends into a thin, papery wing. The above image shows two strikingly different samaras, one from the tree of heaven (Ailanthus altissima) and the other from big-leaf maple (Acer macrophyllum). The maple has a "double samara" composed of two seed-bearing pericarps, each with an elongate wing. The one-seeded fruits split apart and spin by autorotation as they fall to the ground. Some botanists refer to the maple fruit as a schizocarp because it splits into two indehiscent, seed-bearing sections.

See Samaras Of Box Elder & MapleSee The Winged Fruits Of Tipu TreeSee The Winged Fruits Of Ash Tree

5. Nut:One-seeded fruit with hard pericarp.Go To Article About Fruits Called NutsSee Photos of Cashews And Brazil Nuts

A. Fagaceae: Oak (Quercus)

The one-seeded nut of an acorn sits in a cup-shaped involucre composed of numerous overlapping scales. These acorns are from the cork oak (Quercus suber), the bark of which is the source of natural cork.

See The Bark & Wood Of The Cork Oak.

B. Fagaceae: Chestnut (Castanea)

The one-seeded nuts of the American chestnut (Castanea dentata) are produced in a spiny, cup-shaped involucre.

C. Betulaceae: Hazelnut or Filbert (Corylus)

The American filbert (Corylus americana) of the eastern United States produces a one-seeded nut enclosed in an involucre of leafy bracts. In the closely-related species of the Pacific northwestern United States (C. cornuta), the nut is produced in an elongate, tubular involucre.

The beaked filbert (Corylus cornuta) of the Pacific United States produces a one-seeded nut within an elongate, tubular involucre. In this photo, the tubular involucre has been sectioned lengthwise (longitudinally) to expose the hard-shelled nut inside

See An Unusual Filbert-Rubber Tree HybridSee The Bizarre Water Chestnut From Asia

D. Juglandaceae: Pecan & Hickory (Carya)

Note: Some botanists say that the husk of pecans and walnutscontains tissue from the outer pericarp, and insist on referringto these dry fruits as "drupaceous nuts" rather than true nuts.

According to "The Morphology of the Flowers of the Juglandaceae" by W.E. Manning (1940),American Journal of Botany27 (10): 839-852, the fruits ofJuglansandCaryaare drupe-like but not a drupe or dry drupe. The fruit is sometimes called a "tryma" but can be described as a nut.Webster's Third New International Dictionarydescribes a tryma as a nutlike drupe (as the fruit of the walnut or hickory) in which the epicarp and mesocarp separate as a somewhat fleshy or leathery rind from the hard 2-valved endocarp. The tryma is also defined as a drupe with a dehiscent husk, which fits the genusCaryaperfectly.

Pecan (Carya illinoensis): The green, fleshy outer husk or shuck splits into 4 valves, exposing a single large, one-seeded "nut." The husk is composed of leathery tissue derived (at least in part) from the fused sepals. The "tryma" is a fruit type defined as drupe with a dehiscent husk, which fits the pecan perfectly. The "hican" (C. x nussbaumeri) is aCaryahybrid resulting from a cross between the pecan (C. illinoensis) and the shellbark hickory (C. laciniosa).

One-seeded "nuts" of the shellbark hickory (Carya laciniosa). The outer green husk has been removed. Each woody endocarp contains one seed with two conspicuous cotyledons resembling those of a pecan or a walnut. The shellbark hickory generally has larger nuts than the shagbark hickory (C. ovata). Both species of hickory are native to the deciduous forests of the northeastern United States, along with the mockernut (C. tomentosa), pignut (C. glabra) and bitternut (C. cordiformis).

E. Juglandaceae: Walnut (Juglans)

Black walnut (Juglans nigra), a deciduous hardwood tree native to the eastern and central United States. Some botanists refer to walnuts as nuts because the outer green husk contains involucral and calyx tissue, in addition to the outer pericarp. Unlike the closely-related pecan (Carya), the husk does not split into four sections and actually resembles the outer fleshy pericarp of a drupe. According to some botanical references, the outer green layer (husk) of the walnut is part of the pericarp and the hard shell surrounding the seed is the endocarp layer as in coconuts. In true nuts, the hard, indehiscent layer surrounding the seed is the ripened ovary wall or pericarp and the outer husk is composed of involucral tissue (or calyx tissue) that is not part of the ovary wall (pericarp). Depending on the reference, walnuts and pecans are referred to as true nuts or dry drupes. Some authors eloquently avoid this dilemma by calling these fruits drupe-like or "drupaceous nuts."

An intricately-carved English walnut (Juglans regia).Purchased from a vendor on the Great Wall of China.

C. Indehiscent Dry Fruits (Do Not Split Open At Maturity)6. Schizocarp:Seed-bearing carpels split apart, but remain indehiscent.

The schizocarps of sweet fennel (Foeniculum vulgare) are produced in clusters called umbellets, This is typical of plants in the carrot family (Apiaceae). Each schizocarp splits apart into two indehiscent, seed-bearing mericarps, each attached to a stalk called a carpophore.

Schizocarps of sweel fennel (Foeniculum vulgare), each splitting apart into two indehiscent, one-seeded carpels called mericarps. This valuable herb has edible, licorice-flavored leaf stalks and seeds. Ground or whole fennel seeds are used in stuffings, sausages, breads, cookies, cakes, candies and liqueurs.

The schizocarp of filaree (Erodium cicutarium) is composed of five indehiscent, seed-bearing carpels, each with a long, hygroscopic style. When dry, the style coils and literally screws the seed-bearing carpel into the soil. This type of elonbgate schizocarp is typical of plants in the geranium family (Geraniaceae).

Fruits (schizocarps) of filaree (Erodium moschatum), a common and prolific naturalized Mediterranean weed during the spring in southern California. Each fruit is composed of five sections called carpels and a long, slender style column. Since the seed-bearing carpels do not split open, the fruit is considered indehiscent. When they begin to dry out, the mature carpels (each with its own slender style) separate from each other. As the styles uncoil, the carpels are often forcibly ejected. Upon landing on the ground, the free end of the style spirals around like the hand of a clock, twisting the seed-bearing carpel deeper and deeper into the soil. Species ofErodiumare also called storksbill because of the long, beaklike style column on the fruits.

See Schizocarps & Mericarps Of FennelMore Schizocarps: Filaree & CheeseweedSee The Ubiquitous & Painful Puncture Vine

7. Utricle:Small, bladderlike, thin-walled indehiscent fruit.Although they are seldom seen by casual observers, utricles are the characteristic fruit of the duckweed family (Lemnaceae). The dehiscent one-seeded fruits ofAmaranthus(Amaranthaceae) are often called circumscissle utricles because the top half of the fruit separates, exposing a shiny black seed. Note: Wayne's Word contains a lot of additional information about the remarkable duckweed family (Lemnaceae), the undisputed world's smallest flowering plants. Just click on the greenLemnaceae Tabat the top of this page for a complete index to articles and photos.

Utricles of the duckweed family (Lemnaceae). The utricle is a small, bladderlike, thin-walled fruit. It is often compared with a one-seeded achene, except the utricle has a pericarp that is loose and fragile. Because of their small size (usually only 1-2 mm or less), utricles of the duckweed family are seldom seen. In fact, the one-seeded utricles ofWolffiaspecies are the undisputed smallest fruits on earth. The smallest are from the AustralianW. angustaand the Asian/AfricanW. globosa.

See Wolffia Utricles: World's Smallest FruitThe Duckweed Family (Lemnaceae) Home Page

An assortment of winged, one-seeded fruits (utricles) of saltbushes (Atriplex) from the Mojave and Colorado Deserts of the southwestern United States. Saltbushes belong to the goosefoot family (Chenopodiaceae). From left: (A)A. canescens, (B)A. confertifolia, (C)A. hymenelytra, (D)A. polycarpaand (E)A. parryi. The most notable wind-blown species is (A)A. canescens, appropriately named the 4-wing saltbush.

D. Fleshy Fruits (Pericarp Is Fleshy At Maturity)Note:In most fleshy fruits, the carpels are fused together and are notdistinct as in dehiscent dry fruits. A notable exception is the hesperidium.1. Berry:All or most of pericarp fleshy.

Although it is called a "vegetable," the tomato (Lycopersicon esculentum) is technically a botanical fruit referred to as a berry. Most of the interior tissue of a true berry is soft and fleshy.

See Berries Of The GrapeSee Berries Of Tropical GuavasBerries Of The Nightshade FamilyBerries Of The Gooseberry & Currant

Pomegranate: An Unusual Berry

Pomegranate (Punica granatum), showing persistent calyx at the top of fruit. The calyx is cut away on right fruit to show the numerous stamens. The fruit is technically a leathery-skinned berry containing many seeds, each surrounded by a juicy, fleshy aril. The pomegranate tree is native to Africa and the Near East. Hebrews decorated their buildings with pomegranate motifs, and the beautiful, many-seeded fruits became associated with a symbol of fertility and abundance. In Asia, pomegranates were offered to wedding guests who threw them on the floor of the honeymoon suite, shattering the fruits and scattering the bright red seeds. This practice was believed to insure fertility and a large number of offspring for the newlyweds. The French word for a pomegranate is "grenade," which also refers to a hand-thrown bomb that scatters deadly metal fragments (shrapnel) instead of seeds.

Read About Pomegranates & PersimmonsSee A World War II Hand Grenade

2. Pepo:Berry with hard, thick rind.

The watermelon is a good example of a pepo, a berry with a hard, thick rind. This is a triploid, seedless "yellow watermelon" (Citrullus lanatusvar.lanatus). Although it is sold as "seedless," there are some seeds in the fleshy interior.

Some species in the gourd family (Cucurbitaceae) produce a dehiscent capsule rather than a pepo. This wild cucumber fruit (Marah macrocarpus) splits open at one end exposing four chambers, each containing several large seeds.

The Remarkable World Of Gourds

3. Hesperidium:Berry with a leathery rind.

The lemon (Citrus lemon) is a hesperidium, a berry with a leathery rind. The exocarp (peel) contains volatile oil glands (essential oils) in pits. The fleshy interior (endocarp) is composed of separate sections (carpels) filled with fluid-filled sacs (vesicles) that are actually specialized hair cells.

Close-up view of the peel (exocarp) of a lemon (Citrus lemon) showing numerous pits containing volatile oil glands. Essential oils (terpenes and phenolic compounds) in the pits are responsible for the aroma given off when the peels are bruised or ground up. The fragrant perfume called bergamot comes from the fruit rinds ofCitrus bergamia(C. aurantiumssp.bergamia). Essential oils in the pits of skins are extracted by maceration and modern hydraulic presses. The bitter chemical found in the mesocarp and parchment-like layers (partitions) surrounding the sections (carpels) of citrus fruits is limonin.

Magnified longitudinal view of the endocarp of an orange (Citrus sinensis) showing several sections (carpels) filled with numerous fluid-filled "juice sacs." The two lower sections each contain a seed which is surrounded by the fleshy sacs. The sacs (vesicles) are actually swollen (plump), specialized hairs. According to K. Esau (Anatomy of Seed Plants, 1960), the juice sacs originate as multicellular hairs in which the interior of the enlarged distal part breaks down and fills with liquid. The juice sacs constitute the fleshy, edible pulp of an orange and are the source of the sweet juice. A bitter compound called limonin occurs in the mesocarp (rind) and membranous layers (partitions) surrounding the seed-bearing sections of grapefruits and other members of the citrus family (Rutaceae).

See Article About Hesperidiums

4. Drupe:Seed enclosed within a stony endocarp (pit).

A 'California' peach (Prunus persica), a freestone peach grown in California's fertile Central Valley. The fruit is called a drupe because it is composed of three distinct layers: An outer skin or exocarp, a fleshy middle layer or mesocarp, and a hard, woody layer (endocarp) surrounding the seed. The lower pit (removed from another peach) has been sectioned to show the thick, woody layer or endocarp surrounding a single seed.

See Photos Of Stone Fruits (Prunus)

5. Pome:Accessory fruit with thick hypanthium.

'Gala' apple, a cultivated variety ofMalus domestica. The seed-bearing ovary (core) is surrounded by a thick, fleshy hypanthium that is not part of the pericarp. It derived from the fusion of the bases of the perianth segments (petals and sepals). Some references state that the hypanthium may also contain tissue from the receptacle. In the pome, the thickened, fleshy hypanthium is fused with the ovary wall or core. The outer skin of an apple is the multiseriate epidermis of the hypanthium surrounded by a waxy cuticle. Contrary to some references, it is not the exocarp of a ripened ovary. Depending on the variety, the skin contains red anthocyanin pigments. When you eat an apple, you are primarily biting into the hypanthium tissue. You may also consume some of the outer ovary (exocarp and mesocarp) that is fused with the thick hypanthium. Depending on how hungry you are, the inner ovary or seed-bearing core is usually not eaten, at least by most humans. Since the fruit contains tissue not derived from the pericarp, it is called an accessory fruit. This is the typical fruit of certain members of the rose family (Rosaceae), including apple, pear, quince and loquat.

Go To Article About Pomes Of The Rosaceae

6. Aggregate Fruit:Many ovaries derived from a single flower.

Aggregate fruit of a hybrid strawberry (Fragaria x ananassa) showing the individual yellowish-brown, one-seeded achenes embedded in the red, fleshy receptacle. Although the one-seeded achenes represent separate ripened ovaries, each strawberry is produced from a single white flower bearing many stamens.

Flower and aggregate fruit of thimbleberry (Rubus parviflorus), a native shrub in the mountains of the western United States. Although the tiny, one-seeded drupelets represent separate ripened ovaries, each aggregate cluster of fleshy drupelets developed from a single white flower.

See Photo Of A Fresh Rose HipGo To Blackberries & Strawberries

7. Multiple Fruit:Many ovaries derived from many individual flowers.

Black mulberry (Morus nigra), a dioecious tree native to western Asia. The bumpy surface of the fruit is due to many tightly-packed, seed-bearing ovaries (drupelets), each with separate styles that appear like black hairs. It is technically a multiple fruit (called a syncarp) composed of a cluster of drupelets superficially resembling a blackberry; however, unlike a blackberry, each drupelet arises from a separate, minute, unisexual (female) flower. Each monocarpellate pistil (also referred as a gynoecium) consists of a forked stigma, a short style and a spherical ovary. In the aggregate fruit of a blackberry, all the drupelets of the cluster (syncarp) come from a single flower. Seedless, parthenocarpic mulberry fruits are produced without pollination.

Identification Of Major Fruit Types

This is a simplified classification of major fruit types that follows most general botany textbooks and plant identification manuals. There are many fruits that don't exactly fit these major categories, especially certain berry-like and drupe-like fruits. For an in-depth study of fruit types, please refer to theSystematic Treatment of Fruit Typesby Richard Spjut (Memoirs of New York Botanic Garden, Volume 70, 1994). This scholarly article is based on extensive research of classical fruit nomenclature dating back to the 18th century.Top of FormMajor Types Of Fruits:

Bottom of FormI. Simple Fruits:A single ripened ovary from a single flower.A. Fleshy Fruits:All of most of the ovary wall (pericarp) is soft or fleshy at maturity.1. Berry:Entire pericarp is fleshy, although skin is sometimes tough; may be one or many seeded. E.g. grape, tomato, papaya, pomegranate, sapote, persimmon, guava, banana and avocado. The latter two fruits are often termed baccate (berry-like). The banana fruit is a seedless, parthenocarpic berry developing without pollination and fertilization. In the pomegranate, the edible part is the fleshy layer (aril) around each seed. For photos of many of these berries, look them up by their common name in the Wayne's WordIndex. According to Spjut (1994), the pepo is not limited to the gourd family (Cucurbitaceae). The papaya (Carica) is a pepo because of its thick outer rind. He also considers the banana (Musa) to be pepo. The pomegranate has a persistant calyx and endocarp reminiscent of a pome, and membranous partitions, juicy seed vesicles, and a leathery exocarp similar to a hesperidium. Spjut classifies the pomegranate as a "balusta." Berry-like fruits, such as the avocado (Persea) and kiwi (Actinidia) are called a "bacca."Unusual Fruit Of The PomegranateSee Papaya Fruit (Carica papaya)

2. Pepo:Berry with a hard, thick rind; typical fruit of the gourd family (Cucurbitaceae). E.g. watermelon, cucumber, squash, cantelope and pumpkin.The Remarkable World Of Gourds

3. Hesperidium:Berry with a leathery rind and parchment-like partitions between sections; typical fruit of the citrus family (Rutaceae). E.g. orange, lemon, grapefruit, tangelo and kumquat.See Article About Hesperidiums

4. Drupe:Fleshy fruit with hard inner layer (endocarp or stone) surrounding the seed. E.g. peach, plum, nectarine, apricot, cherry, olive, mango and almond. Some botanists also include the fruits of walnuts, pecans, date palms, macadamia nuts, pistachio nuts, tung oil and kukui nuts as drupes because of their outer, green, fleshy husk and stony, seed-bearing endocarp. These latter fruits are also called drupaceous nuts. The coconut is considered a dry drupe with a green, waterproof outer layer (exocarp), a thick, buoyant, fibrous husk (mesocarp) and a hard, woody, inner layer (endocarp) surrounding the large seed. The actual seed embryo is embedded in the coconut meat (endosperm). Nutrient-rich coconut milk is liquid endosperm that has not formed firm tissue with cell walls. According to Spjut (1994), the fruit of a coconut (Cocos) is a "nucleanium." [There is considerable disagreement among authorities about the classification of some of these fruits. For example, the California Macadamia Society considers the macadamia nut to be a follicle. See section B-1 below under dry, dehiscent fruits.]Note: A number of so-called nuts are probably better placed in the drupe category. This is especially true of the walnut family (Juglandaceae), although some older references still consider these fruits to be nuts. In hickory & pecan (Carya) the outer husk or shuck splits into four valves, exposing the hard, indehiscent nut . According to many botanists, the outer husk is part of the pericarp, and the hard, inner layer surrounding the seed is the endocarp; therefore, these fruits are technically drupes or drupaceous nuts. Walnut & butternut (Juglans), two additional members of the walnut family (Juglandaceae), have similar drupe-like fruits. The outer green husk resembles the outer pericarp (exocarp and mesocarp) of a drupe. For this reason, walnuts are sometimes referred to as dry drupes, and the hard shell surrounding the seed is considered to be the endocarp layer as in coconuts. In true nuts, the hard, indehiscent layer surrounding the seed is the entire ovary wall or pericarp, and the outer husk is composed of involucral tissue that is not part of the ovary wall or pericarp. According to most botanical references, the outer green layer (husk) of the walnut is part of the pericarp and the hard shell surrounding the seed is really the endocarp. Therefore, walnuts and pecans probably fit the dry drupe category rather than a true nut. Some authors elegantly avoid this dilemma by calling these fruits drupe-like or "drupaceous nuts."According to "The Morphology of the Flowers of the Juglandaceae" by W.E. Manning (1940),American Journal of Botany27 (10): 839-852, the fruits ofJuglansandCaryaare drupe-like but not a true drupe or dry drupe. The fruit is sometimes called a "tryma" but can be described as a nut.Webster's Third New International Dictionarydescribes atrymaas a nutlike drupe (as the fruit of the walnut or hickory) in which the epicarp (exocarp) and mesocarp separate as a somewhat fleshy or leathery rind from the hard 2-valved endocarp. According to Spjut (1994), the walnut (Juglans) is a pseudodrupe and the pecan (Carya) is a "tryma."Go To Article About Fruits Called Nuts

5. Pome:Ovary or core surrounded by edible, fleshy receptacle tissue (hypanthium or fleshy floral tube) that is really not part of the pericarp. The actual ovary or core is usually not eaten, at least by most humans. This is typical fruit of certain members of the rose family (Rosaceae), including apple, pear, quince and loquat.Go To Article About Fruits Of The Rosaceae

B. Dry Fruits:Pericarp dry at maturity.1. Dehiscent Dry Fruits:Pericarp splits open along definite seams.a. Legume:An elongate "bean pod" splitting along two seams; typical fruit of the third largest plant family, the legume family (Leguminosae or Fabaceae). The pod represents one folded modified leaf or carpel that is fused along the edges. E.g. black locust, redbud, acacia, coral tree, orchid tree, wisteria and many more genera. Note: Some legume fruits are indehiscent, including the carob tree, mesquite and honey locust. In addition, some legume fruits are oblong, rounded, kidney-shaped (reniform), or coiled (spiral-shaped), such as sweet clover (Melilotus albaandM. officinalis), black medic (Medicago lupulina), bur clover (M. polymorpha) and alfalfa (M. sativa). Some specialized legume fruits (called loments) break apart into indehiscent one-seeded joints. A good example of a loment is the very effective hitchhiker called stick-tights or beggar's-ticks (Desmodium cuspidatum).See Hitchhiking Loments Attached To SocksSee The Slender Loments Of Crown Vetch

b. Silique:A slender, dry, dehiscent fruit that superficially resemble a legume, except the mustard silique is composed of two carpels with a partition or septum down the center (i.e. between the two carpels or valves). [The legume fruit is composed of a single carpel and does not have the central partition or septum.] This is the typical fruit of the mustard family (Cruciferae or Brassicaceae). E.g. field mustard, turnip and cabbage (Brassicaspecies), stock (Mathiola), wallflower (Erysimum) and London rocket (Sisymbrium). The silicle is a shortened (less elongate) version of a silique, including sweet alyssum (Lobularia), peppergrass (Lepidium) and shepherd's purse (Capsella). [Note: As with legumes there are a few exceptions to the typical form of siliques and silicles. In wild radish (Raphanus) the silique does not split lengthwise, but instead it breaks transversely into several seed-bearing joints. In lace pod (Thysanocarpus) the silicles are indehiscent.]See Siliques & Silicles Of The Mustard Family

c. Capsule:Seed pod splits open is various ways and usually along several definite seams. Capsules typically split open into well-defined sections or carpels which represent modified leaves. This is a very common dry fruit found in many different plant families. E.g.Catalpa,Jacaranda,Pittosporum,Aesculus,Agave,Yucca,Eucalyptus, devil's claw (Proboscidea), floss silk tree (Chorisia), kapok tree (Ceiba) and castor bean (Ricinus communis). Capsules may split open along the locules (loculicidal), along the septa (septicidal), through pores (poricidal), or the entire top of the capsule separates as a single lid-like section (circumscissile). A common landscaping tree in southern California called the golden-rain tree (Koelreuteria) produces bladder-like capsules that are loculicidally dehiscent into three valves. The opium poppy (Papaver somniferum) produces a classic poricidal capsule in which the tiny seeds fall out of the pore-like windows as the capsule shakes in the wind. The edible weed called purslane (Portulaca) has a many-seeded circumscissile capsule. The Mexican jumping bean (Sebastiana pavoniana) produces a 3-carpellate capsule, each carpel bearing a seed. Sometimes the carpel is occupied by a special moth larva that eats the seed and moves its one-room carpel container by contorting and hurling its body. In the liquidambar tree (Liquidambar styraciflua) the globose fruiting heads are composed of numerous tiny capsules, each bearing one or two winged seeds and a number of aborted ovules (immature seeds). It should be noted here that some capsules are indehiscent. Their carpels do not separate and release the seeds. Two examples of plants with indehiscent capsules are the South African baobab tree (Adansonia digitata) and two species of South African gardenias (Gardenia thunbergiiandG. volkensii). The seed pods of South African gardenias are chewed opened by large herbivores, and the seeds are dispersed in their feces. Spjut (1994) classifies the unusual fruit of the devil's claw (Proboscidea) as a "ceratium," a capsular fruit that opens by a separation or break in the pericarp layers.Capsule Cluster Of Liquidambar TreeSee Circumscissile Capsule Of PurslaneSee Exploding Capsules Of Witch HazelSee Article About Mexican Jumping BeansDevil's Claws: Amazing Hitchhiking CapsulesOpium Poppy Capsule: Source Of Raw OpiumIndehiscent Capsules of South African BaobabIndehiscent Capsules of South African Gardenias

d. Follicle:A single ripened ovary (representing a single modified leaf or carpel) that splits open along one seam. The follicle may occur singly (as in milkweed) or in clusters: two in oleander, 2-5 in peony, 3 in larkspur, 5 in columbine and 4-5 in bottle tree (Sterculia or Brachychiton). The cone-like fruit of the magnolia tree is an aggregate of many small follicles, each containing a single bright red seed. The term apocarpous refers to flowers with separate and distinct carpels, such as delphiniums and columbines of the buttercup family (Ranunculaceae). Although it also belongs to the buttercup family, the fused (syncarpous) carpels ofNigellaform a many-seeded capsule.Parachute Seeds Of The MilkweedFollicles Of Scarlet Larkspur & PeonyFollicle Of The Indian Almond (Sterculia)Follicles Of The Primitive Magnolia Family

2. Indehiscent Dry Fruits:Pericarp does not split open. These fruits usually contain only one seed.a. Achene:Very small, one-seeded fruit, usually produced in clusters. At maturity the pericarp is dry and free from the internal seed, except at the placental attachment. This is the typical fruit of the largest plant family, the sunflower family (Compositae or Asteraceae). Examples of this type of fruit include the sunflower (Helianthus), buttercup (Ranunculus) and sycamore (Platanus). In the sycamore, the globose fruiting heads are composed of tiny, one-seeded achenes interspersed with hairs (some authors refer to these individual fruits as nutlets). [The globose heads of the liquidambar tree are actually composed of numerous tiny capsules.]See Minute Achenes Of Dwarf FluffweedSee Achenes Of The Buckwheat FamilySee Achenes Of The Sunflower FamilySee Parachute Achenes Of Dandelions

b. Anthocarp:In the four o'clock family (Nyctaginaceae), individual apetalous flowers have a tubular, petaloid calyx that resembles a sympetalous corolla. The lower portion of the calyx tightly enwraps the one-seeded achene and is persistent around the fruit as an anthocarp. The calyx base plus the enclosed seed-bearing achene is the unit of dispersal. In some members of the Nyctaginaceae, the persistent calyx base bears sticky glandular projections that aid in dispersal by adhering to the bodies of animals. This is especially true in pisonia trees (Pisonia umbellifera) in which the numerous glutinous anthocarps stick to the feathers of seabirds. This is an effective method of dispersal to distant atolls and islands of the South Pacific region. Sometimes a hapless seabird is completely covered by clusters of the sticky anthocarps, to the point where flight is difficult or impossible. Unable to remove the water-resistant, glue-like anthocarps from its feathers, the seabird drowns in the surf and is consumed by ravenous beach crabs.See Anthocarp Of Desert San VerbenaSee Flower Branch Of The Pisonia Tree

c. Grain or Caryopsis:A very small, dry, one-seeded, indehiscent fruit in which the actual seed coat is completely fused to the ovary wall or pericarp. The outer pericarp layer or husk is referred to as the bran, while the inner, seed layer is called the germ. This is the characteristic fruit of the large grass family (Gramineae or Poaceae). The grain is truly a fruit (not a seed) because it came from a separate ripened ovary within the grass inflorescence. This is the number one source of food for people on the earth. E.g. Corn (maize), wheat, rice, rye, barley, oats, Johnson grass, Bermuda grass and many more species. In corn grains, the main white material that explodes when the grains are heated is endosperm tissue within the seed. Pressure (water vapor) builds up within the grains until they literally explode.Photos Of Cereal GrassesJob's Tears & Corn (Maize)Wind Dispersal Of Grasses (1)Wind Dispersal Of Grasses (2)Bamboo: Remarkable Giant Grass

d. Schizocarp:A small dry fruit composed of two or more sections that break apart; however, each section or carpel (also called a mericarp) remains indehiscent and contains a single seed. Because the seed-bearing sections or carpels (called mericarps) do not split open, this type of fruit is usually placed under indehiscent dry fruits. This is the characteristic fruit of the carrot family (Umbelliferae or Apiaceae). E.g. Carrot (Daucus), celery (Apium) and sweet fennel (Foeniculum vulgare). Other examples of schizocarps include filaree or stork's bill (Erodium) and cheeseweed (Malva), two common weeds in southern California. In these weeds, the seed-bearing carpels (mericarps) separate from each other, but remain indehiscent. Gynoecium is a collective term for the carpels of a flower. Biologists commonly refer to this floral unit as a pistil. Monocarpous flowers are composed of one carpel (a simple pistil). The terms apocarpous and syncarpous refer to compound pistils composed of more than one carpel. Apocarpous flowers contain two or more distinct carpels. In syncarpous flowers, two or more carpels are fused together. In cheeseweed, the carpels are attached to a central, conical connection stalk, but separate from this stalk at maturity. Some authors consider the fruit of the maple (Acer) to be a schizocarp because it splits into two indehiscent, seed-bearing carpels; however, because of the wing on each seed-bearing carpel, other botanists refer to maple fruits as double samaras (see the samara fruit).One of the most painful schizocarps is the puncture vine (Tribulus terrestris). When dry, the spiny fruit splits into indehiscent, seed-bearing sections (carpels). The spines of each section are arranged so that one is always facing upward, like the medieval weapon called a caltrop. The spiny, seed-bearing burs readily penetrate bare feet, shoes and rubber tires.See Schizocarps & Mericarps Of FennelMore Schizocarps: Filaree & CheeseweedSee The Ubiquitous & Painful Puncture Vine

e. Samara:Small, winged, one-seeded fruit, usually produced in clusters on trees. E.g. Maple (Acer): a double samara, ash (Fraxinus), elm (Ulmus) and tree of heaven (Ailanthus). Samaras resemble the winged seeds of a pine, but they are truly one-seeded fruits with a pericarp layer surrounding the seed. The leguminous tipu tree (Tipuana tipu) has a winged fruit that certainly resembles a samara even though it belongs to the legume family (Leguminosae or Fabaceae). Like auto-rotation of helicopters, the samaras spin as they sail through the air, an effective method of dispersal. Richard Spjut (1994) classifies some of the larger winged fruits ofShorea(Diptocarpaceae) andGyrocarpus(Hernandiaceae) as a "pseudosamara."Whirling Nut (Gyrocarpus)See Samaras Of Box Elder & MapleSee The Winged Fruits Of Tipu TreeSee The Winged Fruits Of Ash Tree

f. Nut:Larger, one-seeded fruit with very hard pericarp, usually enclosed in a husk or cup-like involucre. Unfortunately, the above reference by Richard Spjut does not use the term "nut" as a distinct fruit type.(1) Acornof oak (Quercus): The actual nut sits in a cup-shaped involucre of imbricate (overlapping) scales. Classified as a "glans" by Richard Spjut (1994).(2) Chestnut(Castanea), beech (Fagus) & chinquapin (Castanopsis): One or more nuts sit in a spiny, cup-shaped involucre. Classified as a "trymosum" by Richard Spjut (1994).(3) Hazelnutor filbert (Corylus): Nut sits in a leafy (C. americana) or tubular (C. cornuta) involucre. Classified as a "diclesium" by Richard Spjut (1994).(4) Walnut(Juglans) and pecan (Carya) are placed in the drupe category (section A-4) above, although some botanists maintain that they are true nuts. In true nuts, the hard, indehiscent layer surrounding the seed is the entire ovary wall or pericarp, and the outer husk is composed of involucral tissue that is not part of the ovary wall or pericarp. According to most botanical references, the outer green layer (husk) of the walnut is part of the pericarp and the hard shell surrounding the seed is really the endocarp. Therefore, walnuts and pecans probably fit the dry drupe category rather than a true nut. Other authorities claim that the walnut husk is composed of involucral tissue, perianth and an outer layer of pericarp, but is not totally derived from the pericarp. However, since the walnut husk contains pericarp tissue (at least in part), and is not entirely derived from involucral (non-pericarp) tissue, Wayne's Word considers the walnut to be drupaceous rather than a true, undisputed nut. Remember that scientific knowledge is constantly being scrutinized and changed, and the exact classification of dubious, borderline fruits such as the walnut are open for review and modification. The walnut is classified as a "pseudodrupe" by Richard Spjut (1994). See discussion about walnuts underdrupes(section A-4 above).Note: Brazil nuts are seeds produced in a large, woody capsule. Cashews are nuts with a hard shell that is removed before shipment to food stores. The cashew "nut" (drupaceous nut) is produced at the summit of a fleshy receptacle called the "cashew apple." Pine nuts are actually gymnosperm seeds produced in a woody, ovuliferous seed cone. The peanut (Arachis hypogea) is actually a seed with a papery seed coat, typically two seeds enclosed in a dehiscent pod called a legume. After fertilization, the flower stalk of the peanut curves downward, and the developing fruit (legume) is forced into the ground by the proliferation and elongation of cells under the ovary. The peanut pod subsequently develops underground. For more fruits called "nuts" refer to the above section A-4 about drupes and drupaceous nuts.Go To Article About Fruits Called NutsPhotos of Cashews And Brazil NutsSee Photos of the Peanut Plant

g. Utricle:Small, bladderlike, thin-walled, one-seeded, indehiscent fruit. Although it is seldom seen by casual observers, this is the characteristic fruit of the duckweed family (Lemnaceae). The dehiscent one-seeded fruits ofAmaranthus(Amaranthaceae) are often called circumscissile utricles because the top half of the fruit separates, exposing a shiny black seed.See Wolffia Utricles: World's Smallest Fruit

Note: Wayne's Word contains a lot of additional information about the remarkable duckweed family (Lemnaceae), the undisputed world's smallest flowering plants. Just click on the green Lemnaceae tab for a complete index to articles and photos.

II. Aggregate Fruits:A cluster or aggregation of many ripened ovaries (fruits) produced from a single flower. In blackberries and raspberries (Rubus), the individual fruits are tiny, one-seeded drupes or drupelets. Since all the seed-bearing ovaries (carpels) form a fused cluster, the fruit is also called a syncarp. In strawberries (Fragaria), the individual fruits are tiny, one-seeded achenes imbedded in a sweet, fleshy receptacle. Another term for an aggregate cluster of ovaries all derived from a single flower is the "etaerio." In fact, a rose hip (Rosa) eaten as an entire fruit could be considered an etaerio of achenes enclosed by a fleshy receptacle. Fruits of the genusAnnona(Annonaceae), including the sugar apple (A. squamosa), cherimoya (A. cherimola), custard apple (A. reticulata) and soursop (A. muricata) resemble large fleshy berries with scales or projections on the outer surface. They are actually composed of many ovaries fused together and are technically aggregate fruits called syncarps. They are not multiple fruits because they develop from a single flower bearing many pistils (carpels).See Photo Of A Fresh Rose HipGo To Blackberries & Strawberries

III. Multiple Fruits:A cluster of many ripened ovaries (fruits) produced by the coalescence of many flowers crowded together in the same inflorescence, typically surrounding a fleshy stem axis. E.g. mulberry, osage orange, pineapple, breadfruit and jackfruit. In the mulberry (Morus), the individual fruits are tiny drupes called drupelets. In the pineapple (Ananas), the individual fruits are berries imbedded in a fleshy, edible stem, each berry subtended by a jagged-edged bract where the original flower was attached. The fleshy spadix ofMonstera deliciosais also a multiple fruit because it is derived from numerous, tightly-packed female flowers. Another term for multiple fruits composed of a fleshy spike or raceme of tightly packed ovaries is thesorosis.Note: Fig trees (Ficus) produce an edible multiple fruit called a syconium. It is a fleshy, flask-shaped structure (inflorescence) lined on the inside with numerous female flowers, each forming a tiny, one-seeded drupelet. Seed formation requires a symbiotic wasp that enters the syconium and pollinates the female flowers. Smyrna and California-grown Calimyrna figs require wasp pollination. Other fig varieties will produce edible, seedless, parthenocarpic syconia without pollination. This is a very complex and fascinating story that is discussed in several Wayne's Word articles. Look up "fig" under the blue index tab for more information.Go To Article & Photos Of PineapplesSee Jackfruit, Breadfruit & Osage OrangeSee The Amazing Calimyrna Fig & Its WaspFlowers & Multiple Fruit (Syncarp) Of Mulberry

Miscellaneous Notes On Fruit Types:Some trees produce seeds and pollen in separate inflorescences called catkins or aments. This includes monoecious species with both male and female catkins on the same tree; and dioecious species with separate male and female trees. In birch (Betula) and alder (Alnus), the seeds (nutlets) are produced in a woody, cone-like catkin. In other trees, such as oak (Quercus), only pollen is produced in the catkins.In true cone-bearing trees, the immature seeds (ovules) are borne at the surface of ovuliferous scales instead of enclosed within an a ovary as in flowering plants. Because the ovules are exposed to the wind-blown pollen during the pollination period, these trees are referred to as gymnosperms (which means naked seeds). The ovuliferous scales collectively form a woody seed cone sealed with sticky resin. At maturity (in one or two years depending on the species), the scales dry and separate from each other, thus releasing the winged seeds. In junipers (Juniperus) the scales are fleshy and fused together, and the seed cones superficially resemble berries. In the maidenhair tree (Ginkgo biloba), fern pine (Podocarpus), and the California nutmeg (Torreya californica), the large seed with a fleshy outer coat is borne naked on the branchlets. In the yew tree (Taxus) the naked seed is borne in a fleshy, cup-like structure called an aril.