Asimina triloba explained

Asimina triloba, the American papaw, pawpaw, paw paw, or paw-paw, among many regional names, is a small deciduous tree native to the eastern United States and southern Ontario, Canada, producing a large, yellowish-green to brown fruit.[1] [2] [3] Asimina is the only temperate genus in the tropical and subtropical flowering plant family Annonaceae, and Asimina triloba has the most northern range of all.[4] Well-known tropical fruits of different genera in family Annonaceae include the custard-apple, cherimoya, sweetsop, ylang-ylang, and soursop.

The pawpaw is a patch-forming (clonal) understory tree of hardwood forests, which is found in well-drained, deep, fertile bottomland and also hilly upland habitat.[5] It has large, simple leaves with drip tips, more characteristic of plants in tropical rainforests than within this species' temperate range.[6] Pawpaw fruits are the largest edible fruit indigenous to the United States[7] (not counting squashes, which are typically considered vegetables rather than fruit for culinary purposes, although in botany they are classified as fruit).

Pawpaw fruits are sweet, with a custard-like texture, and a flavor somewhat similar to banana, mango, and pineapple. They are commonly eaten raw, but are also used to make ice cream and baked desserts. However, the bark, leaves, fruit, and seeds contain the potent neurotoxin annonacin.[8]

Names

This plant's scientific name is Asimina triloba. The genus name Asimina is adapted from the Native American (probably Miami-Illinois[9]) name assimin or rassimin[10] combining the root terms rassi= “divided lengthwise into equal parts” and min= “seed, fruit, nut, berry, etc.”[11] through the French colonial French: asiminier.[12] The specific epithet triloba in the species' scientific name refers to the flowers' three-lobed calyx (green in photo at right) and doubly three-lobed corollas,[10] the shape not unlike a tricorne hat.

The common name of this species is variously spelled pawpaw, paw paw, paw-paw, and papaw. It probably derives from the Spanish papaya, an American tropical and subtropical fruit (Carica papaya) sometimes also called "papaw", perhaps because of the superficial similarity of their fruits and the fact that both have very large leaves. The name pawpaw or papaw, first recorded in print in English in 1598, originally meant the giant herb Carica papaya or its fruit (as it still commonly does in many English-speaking communities, including Australia, New Zealand, and South Africa). Daniel F. Austin's Florida Ethnobotany[13] states that:

The original "papaw" ... is Carica papaya. By 1598, English-speaking people in the Caribbean were calling these plants "pawpaws" or "papaws" ... [yet later, when English-speakers settled in] the temperate Americas, they found another tree with a similarly aromatic, sweet fruit. It reminded them of the "papaya", which had already become "papaw", so that is what they called these different plants ... By 1760, the names "papaw" and "pawpaw" were being applied to A. triloba.

Yet A. triloba has had numerous local common names, many of which compare it to a banana rather than to Carica papaya. These include wild banana, prairie banana, Indiana banana, Hoosier banana, West Virginia banana, Kansas banana, Kentucky banana, Michigan banana, Missouri banana, Appalachian banana, Ozark banana, Indian banana, banango, and the poor man's banana, as well as American custard apple, asimoya,[14] Quaker delight, and hillbilly mango.[15]

Several tribes of Native Americans have terms for the pawpaw such as riwahárikstikuc (Pawnee),[16] tózhaⁿ hu (Kansa),[17] and Choctaw: umbi (Choctaw).[18]

Description

A. triloba is a large shrub or small tree growing to a height of 35feet, rarely as tall as 45feet, with trunks 8- or more in diameter. The large leaves of pawpaw trees are clustered symmetrically at the ends of the branches, giving a distinctive imbricated appearance to the tree's foliage.[10]

The leaves of the species are simple, alternate and spirally arranged, entire, deciduous, obovate-lanceolate, 10- long, 4- broad, and wedge-shaped at the base, with an acute apex and an entire margin, with the midrib and primary veins prominent. The petioles are short and stout, with a prominent adaxial groove. Stipules are lacking. The expanding leaves are conduplicate, green, covered with rusty tomentum beneath, and hairy above; when fully grown they are smooth, dark green above, and paler beneath. When bruised, the leaves have a disagreeable odor similar to a green bell pepper. In autumn, the leaves are a rusty yellow, allowing pawpaw groves to be spotted from a long distance.[10] [19]

Pawpaw flowers are perfect and protogynous,[20] about 1- across, rich red-purple or maroon when mature, with three sepals and six petals. They are borne singly on stout, hairy, axillary peduncles. The flowers are produced in early spring at the same time as or slightly before the new leaves appear, and have a faint fetid or yeasty smell.[10] [19] [21]

The fruit of the pawpaw is a large, yellowish-green to brown berry, 2- long and 1- broad, weighing from 0.7–, containing several brown or black seeds NaN- in diameter embedded in the soft, edible fruit pulp. The conspicuous fruits begin developing after the plants flower; they are initially green, maturing by September or October to green, yellowish green, or brown. When mature, the heavy fruits bend the weak branches down. Full ripening often happens only after the fruit falls naturally, thus signifying a seed dispersal strategy aimed at ground-based, rather than arboreal, mammals.[10] [19]

Other characteristics:

Range and ecology

Asimina triloba is a member of the Annonaceae family, commonly referred to as the “custard-apple” or “soursop” family. Annonaceae are a diverse group comprising the single largest family of the order Magnoliales. They are a tropical family consisting of 112 accepted genera with about 2,200 species spread primarily across South America, Africa, and Southeast Asia.[24]

The pawpaw is an exception to this pattern, as it is the most temperate member of its family. Its range extends as far north as the southern portion of Ontario, Canada. Within the United States, pawpaw is native to the eastern, southern, and midwestern states, ranging from New York westward to southeastern Nebraska, southward to eastern Texas and the panhandle of Florida.[25] [26] The tree is commonly found in the wild within or along the slopes of floodplains and shady, rich bottomlands,[27] but it requires somewhat elevated slopes because it has a deep-reaching taproot.

Hybridization with other Asimina species

The common pawpaw is the largest and most well known of the 13 species of the Asimina genus in North America. Of those 13, 11 prefer very warm weather and have ranges rarely extending northward of Florida or coastal Alabama. Their ranges do not overlap with Asimina triloba.

One southern USA species, Asimina parviflora, does overlap in range with pawpaw. This species is smaller than pawpaw in both its flower and its woody growth. A. parviflora is more shrublike, rarely growing even a third as tall as pawpaw. Genomically verified hybrids of A. triloba and A. parviflora have been classified as Asimina piedmontana.[28]

Pollination

Pawpaw are self-incompatible, meaning pollen cannot fertilize flowers on the same plant. This, coupled with the pawpaw's tendency to form clonal patches can reduce fertilization success. A single patch consisting of many stems may therefore produce no fruit if all stems are genetically identical. Fruitless pawpaw patches have been documented in Ohio.[20]

The floral scent of Asimina triloba has been described as "yeasty", which is one of several features that signify a "beetle pollination syndrome".[29] Other floral features of pawpaw indicative of beetle pollination include petals that curve over the downward-pointing flower center, along with food-rich fleshy bases of the inner whorl of petals. A "pollination chamber" is thereby created at a depth that only small beetles can access during the initial female-receptive stage of floral bloom. As with other well-studied species of Annonaceae, the delay in the shift from female to male floral stage offers beetles a secure, and possibly thermogenic, residence in which not only to feed but also to mate.[30] Receptive stigmas at their arrival, followed by pollen-shedding stamens during pollinator departure, are regarded as an early form of mutualism evolved between plants and insects that is still dominant in the most ancient lineages of flowering plants, including the Magnoliids (of which Annonaceae is the most species-rich taxonomic family).[31]

Beetles are the dominant form of pollinator ascribed for genera and species within the Annonaceae family. However, two species of genus Asimina (Asimina triloba and Asimina parviflora) bear a floral character that has given rise to an alternative hypothesis that carrion or dung flies are their effective pollinators. That floral characteristic is the dark maroon color of the petals.[32] [33] Hence, while no scholarly papers have documented carrion or dung flies as effective pollinators in field observations, the strength of this hypothesis has led to placement of carrion during the bloom time in pawpaw orchards by some horticultural growers.[34]

Professional papers on genus Asimina and its species have warned of the difficulties in discerning whether insects observed on or collected from flowers are effective pollinators or merely casual and thus opportunistic visitors.[33] [35] [36]

A citizen science project in southern Michigan utilized natural history forms of observation, along with video and photo documentation, during a "pawpaw pollinator watch" in May 2021. Two species of tiny sap beetle were reported as the most abundant and the most consistently present insect types at depth within the flowers, and thus as the most likely effective pollinators. The two species are Glischrochilus quadrisignatus and Stelidota geminata. Both are in the taxonomic family Nitidulidae. Nitidulid beetles are described by Clemson University as likely "night flying" pollinators of pawpaw.[37] Larvae and adult beetle stages of Glischrochilus quadrisignatus were also documented by the citizen project on the ground-level side of rotting fruit in a pawpaw orchard in Michigan following the fruit harvest.

Seed dispersal

Until the expansion of humans into North America at the end of the Pleistocene, dispersal of pawpaw seeds would primarily have occurred via the dung of certain megafauna (such as mastodons, mammoths, and giant ground sloths). [38] The fruit of pawpaw is thus recognized as having coevolved with large mammals serving as long-distance seed dispersers.[39] [40]

The megafaunal dispersal syndrome is a common feature of some plants native to the Western Hemisphere, where a large proportion of megafauna went extinct near the end of the glacial episodes. Such fruits are now regarded as evolutionary anachronisms. Their anatomical features, such as seeds too big for today's fruit eaters to swallow and then defecate, means they are no longer well adapted for current ecological conditions.[41]

Another indicator of dispersal adaptation for megafauna is that pawpaw fruit (wild types and most cultivars) tend to remain green or become blotched with brown when at peak ripeness. Mammals (other than primates) rely on olfactory rather than visual clues for discerning ripe fruit, so fruit color is no signal of ripeness for large mammals. An advantage of maintaining green fruit skin throughout the ripening process is that photosynthesis can continue during this time.[42]

Following the extinction of much of the ice age megafauna, bears would have continued dispersing pawpaw seeds in their dung. Hand carrying of fruit and seeds by humans expanding from Asia into North America would have extended the range of long-distance seed dispersal.[27] [43] [44] [45] Humans intentionally continue this role today via horticultural plantings, along with wild plantings as far north as Massachusetts,[46] [47] Pennsylvania,[48] [49] and Michigan.[50] Small mammals, including raccoons, gray foxes, opossums, and squirrels, assist in local movements of seeds.[51]

Interactions with herbivores

Pawpaw defends against herbivory by producing strong-smelling natural toxins known as acetogenins.[52] Pawpaw leaves, twigs, and bark are therefore seldom consumed by rabbits, deer, or goats, nor by insects. However, mules have been seen eating pawpaw leaves in Maryland.[53]

Larvae of the zebra swallowtail (Eurytides marcellus), a butterfly, feed exclusively on young leaves of A. triloba and various other pawpaw (Asimina) species, but do not occur in great numbers on the plants. Chemicals consumed by the caterpillars confer protection throughout the butterflies' lives, as trace amounts of acetogenins remain present, making them unpalatable to birds and other predators.[54] A citizen-led project in Pittsburgh, Pennsylvania is restoring pawpaw along a river for the purpose of encouraging return of the zebra swallowtail.[55] (See image at right.)

Other insects which have evolved the ability to consume pawpaws include Talponia plummeriana, the pawpaw peduncle borer, whose larvae can be found in flowers, and Omphalocera munroei, the asimina webworm, whose larvae mostly feed upon leaves.[56]

Patch-forming clonal growth

Pawpaw is well suited to life as an understory tree. Its large seed enables significant below-ground growth before the above-ground growth needs to access sunlight for photosynthesis. As well, the species is so shade-adapted that propagation of seedlings in nursery and landscape settings may fail if the emerging plants are not protected from direct sunlight.

Patch-forming clonal growth is achieved by way of shallow, horizontally spreading stems (rhizomes). By retaining these interconnections, photosynthates can be shared among the stems (ramets). Stems that access sunlight can grow as tall as 30 feet and will bear the most fruit. Stems that develop under canopy shade tend to curve and bend in quest of sunlight patches, with a greater density of small stems than where the tallest stems have captured the canopy positions.[57]

Pawpaws are not the first to colonize a disturbed site, but because they are capable of growing in deep shade, they can establish from seed beneath mature deciduous trees and then spread into a subcanopy patch. They may even become dominant through time by depriving native canopy trees from re-establishing via seed in a treefall gap, owing to the dense shade within a pawpaw patch. Under such circumstances, the pawpaw subcanopy becomes the forest canopy, albeit at a height half as high as the usual canopy of native trees.[58] Accessing full sunlight, the patch is then capable of producing more fruit.

Shifting dynamics

Pawpaw is predominantly a lowland species associated with moist but well-drained soils. Recently it has been colonizing drier upland forests.[59]

Upslope expansion has been attributed to a lessening of human-set fires within forested habitats of the eastern United States. Unlike common canopy trees such as oaks and pines, pawpaw has no resistance against ground fires. So a reduction in fires has enabled pawpaw, as well as other shade-adapted native trees (including American beech and striped maple), to become more common. As well, because toxins in the bark, twigs, and leaves of pawpaw repel herbivory, forests browsed by overpopulated deer offer pawpaw even more competitive advantages.[60]

Pawpaw exhibits a high tolerance for intense shading, even compared with other shade-adapted species such as striped maple.[61] Pawpaw leaves cast very heavy shade, and this chokes out seedlings and saplings of most canopy species (though not native spring herbs that benefit from the late-leafing habit of pawpaw).[62]   This helps pawpaw outcompete rival species and is a contributor to its increased abundance in forests across its range.

Conservation

On a global (range-wide) scale, the common pawpaw (A. triloba) has a NatureServe global conservation rank of G5 (very common). The species is, however, listed for conservation concern in the northernmost parts of its range, owing to the happenstance of where governmental boundaries exist. In the United States, the species has an N5 (very common), but is considered a threatened species in New York,[63] and an endangered species in New Jersey.[64] In Canada, where the species is found only in portions of southern Ontario,[65] it has a rank of N3 (vulnerable), and a NatureServe subnational conservation rank of S3 (vulnerable) in Ontario. The Ontario Ministry of Natural Resources has given the species a general status of "Sensitive", and its populations there are monitored.

In areas in which deer populations are dense, pawpaws appear to be becoming more abundant locally, since the deer avoid them but consume seedlings of most other woody plants.[66]

Disease

The genus Asimina exists on only one continent, North America.[67] This gives the pawpaw a distinct advantage in the modern world of transcontinental commerce. In contrast to North American tree genera whose ranges extend into Europe or Asia (notably, chestnut and elm), global horticultural trade is therefore unlikely to introduce diseases that could decimate pawpaw.

As for native disease, the pawpaw fares very well. There are no known disease agents (including insects) that are especially damaging. Consequently, planting of pawpaw for landscaping or fruit production requires little to no attention to disease management.[68]

Habitat restoration

Pawpaws are sometimes included in ecological restoration plantings, as they have many characteristics that make them ideal for repair of riparian ecosystems. The tree’s fondness of wet soil and tendency to multiply clonally to form dense and well-rooted thickets can protect against erosion and runoff.[69] As a native species, pawpaw can be planted on river slopes for erosion control, as introduced species formerly used in the eastern United States for this purpose (such as bamboo and Amur honeysuckle) are now discouraged or prohibited because of their invasiveness. The nonexistent commercial demand of pawpaw timber also protects trees used for ecological reasons from potential future harvest.

In the eastern United States, where large predators are almost entirely lacking, pawpaw is one of the few native subcanopy trees whose bark and leaves are too poisonous for deer to browse. It is therefore a viable species for forest understory restoration in areas where fragmented landscapes, dwellings, and parks status preclude hunting as a population control.[70] [71]

Human uses

Uses other than food

The tough, fibrous inner bark of the pawpaw has traditionally been used by Native Americans and settlers in the Midwest for making ropes, fishing nets, and mats,[10] and for stringing fish. Because the exotic emerald ash borer beetle is destroying black ash trees (Fraxinus nigra) in its native range, a basketmaker in Michigan whose ancestors traditionally used this northern species of ash has begun planting pawpaw seeds as a potential fiber replacement.[72] The planting is occurring several hundred miles north of pawpaw's historically native range, so it is an example of assisted migration of a plant in a time of rapid climate change.

Pawpaw logs have been used for split-rail fences in Arkansas.[10] The hard, brown, shiny lima-bean-sized seeds were sometimes carried as pocket pieces in Ohio.[10] Due to the presence of acetogenins, the leaves, twigs, and bark of pawpaw trees can be used to make an organic insecticide.

Edible fruit

Paw paw, raw with skin
Protein:1.2 g
Fat:1.2 g
Carbs:18.8 g
Fiber:2.6 g
Calcium Mg:63
Iron Mg:7
Magnesium Mg:113
Phosphorus Mg:47
Potassium Mg:345
Zinc Mg:0.9
Manganese Mg:2.6
Vitc Mg:18.3
Thiamin Mg:0.01
Riboflavin Mg:0.09
Niacin Mg:1.1
Vita Ug:87
Note:Analysis from Kentucky State University Pawpaw Program

The earliest documented mention of pawpaws is in the 1541 report of the Spanish de Soto expedition, who found Native Americans east of the Mississippi River cultivating what some have identified as the pawpaw. The tree's scientific name (Asimina triloba) comes from the Powhatan word Assimina, which a Jamestown settler transcribed in 1612 as “wheat plum".[73] The Lewis and Clark Expedition consumed pawpaws during their travels.[74] Thomas Jefferson planted it at Monticello, his plantation in Virginia.[74] Legend has it that chilled pawpaw fruit was a favorite dessert of George Washington.[75]

Historically, the pawpaw was a commonly-eaten fruit throughout its native range. With the advent of motor travel and refrigeration, it has been used less commonly to the point of obscurity in favor of other commercial fruits.

As described by horticulturist Barbara Damrosch, the fruit of the pawpaw "looks a bit like mango, but with pale yellow, custardy, spoonable flesh and black, easy-to-remove seeds."[76] Wild-collected pawpaw fruits ripen in late August to mid-September through most of their range, but a month later near their northward limit.[77] They have long been a favorite treat throughout the tree's extensive native range in eastern North America, and on occasion are sold locally at farmers' markets.

Pawpaw fruits have a sweet, custard-like flavor somewhat similar to banana, mango, and cantaloupe,[10] varying significantly by source or cultivar, with more protein than most fruits. Nineteenth-century American agronomist E. Lewis Sturtevant described pawpaws as "a natural custard, too luscious for the relish of most people." Ohio botanist William B. Werthner wrote, "The fruit ... has a tangy wild-wood flavor peculiarly its own. It is sweet, yet rather cloying to the taste and a wee bit puckery – only a boy can eat more than one at a time."[10]

Fresh fruits of the pawpaw are commonly eaten raw, either chilled or at room temperature. However, they can be kept only 2–3 days at room temperature, or about a week if refrigerated.[21] [78] This short shelf-life and difficulty shipping whole are a primary barrier to the success of pawpaw as a commercial fruit. The easily-bruised pawpaw fruits do not ship well unless frozen. Where pawpaws grow, the fruit pulp is also used locally in baked dessert recipes, with pawpaw substituted with volumetric equivalency in many banana-based recipes. The sweet and creamy fruit is commonly mixed into ice cream[21] or blended into pancakes and other breads.[21]

Nutrition

According to a report from the KSU Pawpaw Program (right table), raw pawpaw (with skin) is 19% carbohydrates, 1% protein, 1% fat, and 79% water (estimated). In a 100-g reference amount, the raw fruit provides 80 Calories and is a rich source (20% or more of the Daily Value, DV) of vitamin C (22% DV), magnesium (32% DV), iron (54% DV), and manganese (124% DV). The fruit also contains a moderate amount of vitamin A (11% DV).

Pawpaw fruit is very rich in many minerals and micronutrients compared to most other fruits; apples, oranges, bananas, etc.

Phytochemicals

Pawpaw pulp contains phenolic acids and flavonols, particularly epicatechins and procyanidins.[79] [80] Phytochemical extracts of the bark, leaves, twigs, and seeds contain acetogenins, including the neurotoxin annonacin, as well as other phytochemicals.[81] [82] [83]

Cultivars

Over the years, a variety of cultivars of A. triloba have been developed or discovered,[84] although some have been lost and are no longer available commercially.[74] [85] [86] Most named cultivars derive from the northern parts of the species range.[87]

Kentucky State University (KSU) has a pawpaw research program[88] which seeks to develop methods and varieties to increase the viability of the pawpaw to be grown as a commercial fruit crop.

The named varieties producing large fruit and performing well in Kentucky per research trials are 'NC-1', 'Overleese', 'Potomac', 'Shenandoah', 'Sunflower', 'Susquehanna', 'Wabash', KSU-'Atwood', KSU-'Benson', and KSU-'Chappell'.[89]

Research

Kentucky State University (KSU) has the only full-time pawpaw research program in the world; it was started in 1990 with the aim of developing pawpaw as a new tree-fruit crop for Kentucky. Pawpaw is the largest edible native fruit in North America and has very few diseases compared to other orchard crops. KSU is the site of the USDA National Clonal Germplasm Repository for Asimina species and the pawpaw orchards at KSU contain over 1,700 trees. Research activities include germplasm collection and variety trials, and efforts are directed towards improving propagation, understanding fruit ripening and storage, and developing orchard management practices. Cultivation is best in hardiness zones 5-9 and trees take 7–8 years from seedling to fruiting. KSU has created the three cultivars KSU-'Atwood', KSU-'Benson', and KSU-'Chappell', with foci on better flavors, higher yields, vigorous plants, and low seed-to-pulp ratios.[90] [91] [92]

Cultivation

Cultivation is best in hardiness zones 5-9 and trees take 7–8 years from seedling to fruiting. Cross-pollination of at least two different genetic varieties of the plant is recommended. Scholarly research is insufficient for horticulturalists to adopt best methods for attracting insect pollinators, as effective pollinators have not yet been distinguished from casual insect visitors.[33] Therefore, some growers resort to hand pollination or use pollinator attractants, such as spraying fish emulsion or hanging chicken necks or other meat near the open flowers to attract carrion-feeding beetles.

Pawpaws have not been cultivated for their fruits on the scale of apples or peaches, primarily because pawpaw fruits ripen to the point of fermentation soon after they are picked, and only frozen fruit stores or ships well. Other methods of preservation include dehydration, production of jams or jellies, and pressure canning (using the numerical values for bananas). Methods of separating seeds from the pulp are still in the experimental phase. Mechanical methods are most efficient, but any splitting or injury of seeds can contaminate the remaining pulp with seed poisons.[93]

Cultivation of pawpaws for fruit production has attracted interest, particularly among organic growers, as a fruit with few to no pests that can successfully be grown in its native environment without pesticides. The commercial cultivation and harvesting of pawpaws is strongest in southeastern Ohio[94] and also being explored in Kentucky and Maryland, as well as various areas outside the species' native range, including California,[95] the Pacific Northwest, and Massachusetts. The pawpaw is used for landscaping due to its distinctive growth habit, the appeal of its fresh fruit, and its relatively low maintenance needs once established.[21]

Changing perspectives of the general population towards a healthier and environmentally conscious diet has led to increased interest in the pawpaw as food in recent years. Using pawpaw puree as a substitute for other sweeteners and creamers adds micronutrients such as iron and manganese while typically reducing the total sugar content as well as glycemic index of most recipes. If done correctly this will not negatively impact the quality of baked goods or desserts. In a study conducted using pawpaw puree in muffins, the pawpaw muffins were preferred in the blind taste test over the control (sugar) and other sweeteners (apple puree).[96]

Commercial pawpaw production tends to be less intensive than other fruit trees.[97] Pawpaw requires very little pesticide/herbicide, even when planted as a monoculture. Because of its long taproot, pawpaw grows well even in drier upland plantings. Also attractive to fruit growers is its ability to be grown in more northern climates of the eastern United States and southern Canada than commercial fruit species grown primarily in the warmth of Alabama, Georgia, Florida, and California.[98]

Propagation

Trees are easily grown from seed. Seeds should not be permitted to dry, as they lose viability if they dehydrate to 5% moisture.[99] The seeds need to be stratified by moist cold storage for 60–100 days at NaNF (some publications suggest 90–120 days).[100] They will lose their viability if stored for three years or more; some seeds survive if stored for two years. Germination is hypogeal. This means that the cotyledons remain within the seed coat, acting as a food store for early growth until the plumule emerges from the soil on the epicotyl, or true stem. Because the large seeds contain enough energy to produce a long taproot prior to seeking photosynthetic opportunities above ground, the seed itself will be pushed upward and into the air if shallow planted in standard pots.

Given the 6 to 7 year maturity time and relatively poor success rates for dispersal and germination, it often requires 7 to 10 years for a sapling-to-sapling life cycle to occur for a given individual.[101]

Propagation using cuttings has generally not been successful.

Desirable cultivars are propagated by chip budding or whip grafting onto a root stock. Pawpaw seeds do not grow "true to type" — each individual seed in a fruit is genetically different from the others and from its parent tree. Purchased cultivars do not produce seeds true to type, either, which is why cultivars are all grafted trees. Root sucker seedlings, however, are all genetically identical to their host.

Commercial nurseries usually ship grafted cultivars in containers. Other nurseries, such as the Kentucky Division of Forestry, ship bareroot seedlings for reforestation projects and area homeowners.[102] [103]

Harvesting small stems within a wild pawpaw patch is usually unsuccessful because most are clones of (and still connected to) adjacent stems and therefore lack fully developed roots.

Cultural significance

Old song

A traditional American folk song portrays wild harvesting of pawpaws; Arty Schronce of the Georgia Department of Agriculture gives these lyrics:[21]

He notes that "picking up pawpaws" refers to gathering the ripe, fallen fruit from beneath the trees, and that the "pocket" in the song is that of an apron or similar tie-on pocket, not a modern pants or blue-jeans pocket, into which pawpaws would hardly fit.[21] A "pawpaw patch" refers to the plant's characteristic patch-forming clonal growth habit.

Place names

The pawpaw is the basis for various place and school names in the United States, almost all using the older spelling variant "paw paw".

Art

Other

Further reading

External links

Notes and References

  1. Web site: Jones . Snake C. . Layne . Desmond R. . 2019 . Pawpaw Description and Nutritional Information . 30 December 2019 . dead . 30 December 2019 . https://web.archive.org/web/20191230230839/https://kysu.edu/academics/cafsss/pawpaw/pawpaw-description-and-nutritional-information/ . Kentucky State University Cooperative Extension Program.
  2. Web site: Asimina triloba . College of Agriculture and Life Sciences, North Carolina State University . 2018-12-19 . live . 2018-04-06 . https://web.archive.org/web/20180406224241/https://plants.ces.ncsu.edu/plants/all/asimina-triloba/.
  3. Web site: Layne . DR . 1998-02-24 . Pawpaw . live . https://web.archive.org/web/20190711221948/https://hort.purdue.edu/newcrop/CropFactSheets/pawpaw.html . 2019-07-11 . 2018-12-19 . NewCrop Factsheet, Purdue University.
  4. Huang . Hongwen . Layne . Desmond . Kubisiak . Thomas . July 2000 . RAPD Inheritance and Diversity in Pawpaw (Asimina triloba) . Journal of the American Society for Horticultural Science . 125 . 4 . 454–459 . 10.21273/JASHS.125.4.454 . free .
  5. Web site: Native Pawpaw Tree . 6 October 2022 . North Carolina State University. September 6, 2017 .
  6. Web site: Pankau . Ryan . Pawpaw . Illinois Extension Service . March 28, 2018 . University of Illinois Urbana-Champaign . 6 October 2022.
  7. Web site: Matthews . Elizabeth . 21 September 2021 . Pawpaw: Small Tree, Big Impact . U.S. National Park Service . 16 December 2021 . en.
  8. Avalos . J . Rupprecht . J. K. . McLaughlin . J. L. . Rodriguez . E . 1993 . Guinea pig maximization test of the bark extract from pawpaw, Asimina triloba (Annonaceae) . Contact Dermatitis . 29 . 1 . 33–5 . 10.1111/j.1600-0536.1993.tb04533.x . 8365150 . 41590523.
  9. Chamberlain . Alexander F. . Alexander Francis Chamberlain . 1 December 1902 . Algonkian Words in American English: A Study in the Contact of the White Man and the Indian. . The Journal of American Folklore . American Folklore Society . 15 . 59 . 240–267 . 10.2307/533199 . 0021-8715 . 533199.
  10. Book: Werthner, William B. . Some American Trees: An intimate study of native Ohio trees . The Macmillan Company . 1935 . New York . xviii + 398 pp.
  11. Chamberlain . Alexander F. . October 1902 . Algonkian Words in American English: A Study in the Contact of the White Man and the Indian . The Journal of American Folklore . 15 . 59 . 240–267 . 10.2307/533199 . 533199 . 0021-8715.
  12. Book: Sargent, Charles Sprague . Manual of the trees of North America (exclusive of Mexico) . Houghton Mifflin Company: The Riverside Press Cambridge . 1933 . Boston and New York . xxvi + 910.
  13. CRC Press, 2004, p.122.
  14. Web site: 1 November 1996 . The Asimoya . https://web.archive.org/web/20180329063352/http://rfcarchives.org.au/Next/Fruits/CustardApple/Asimoya11-96.htm . 29 March 2018 . live . 26 November 2017 . The Archives of the Rare Fruit Council of Australia.
  15. Web site: Schweitzer . Ally . 15 September 2017 . This Once-Obscure Fruit Is On Its Way To Becoming PawPaw-Pawpular . live . https://web.archive.org/web/20180405152933/https://www.npr.org/sections/thesalt/2017/09/15/550985844/this-once-obscure-fruit-is-on-its-way-to-becoming-pawpaw-pawpular . 5 April 2018 . 4 April 2018 . NPR .
  16. Web site: American Indian Studies Research Institute . zia.aisri.indiana.edu . live . https://web.archive.org/web/20181213143503/http://zia.aisri.indiana.edu/~dictsearch/ . 2018-12-13 . 2018-12-18.
  17. Web site: English to Kanza Dictionary . kawnation.com . live . https://web.archive.org/web/20161011115616/http://www.kawnation.com/WebKanza/LangResources/nglshknzdctnry.pdf . 2016-10-11 . 2018-12-18.
  18. Book: Byington, Cyrus . A dictionary of the Choctaw language . United States Government Printing office . 1915 . 1566321085 . 53387982 . Washington D.C. . 359 . 2018-12-18.
  19. Book: Keeler, Harriet L. . Our Native Trees and How to Identify Them . Charles Scribner's Sons . 1900 . New York . 20–23 . 2019-11-07.
  20. LaGrange . Renee L . Tramer . Elliot J. Geographic Variation in Size and Reproductive Success in the Paw Paw (Asimina triloba) . Ohio Journal of Science . 1985 . 85 . 1 . 40–45 . 5658221. 15 July 2024. The Ohio State University Libraries Knowledge Bank.
  21. Web site: Krewer . Gerard W. . Crocker . Thomas F. . Bertrand . Paul F. . Horton . Dan L. . 2015-02-20 . Minor Fruits and Nuts in Georgia - Pawpaw, Bulletin 992 . live . https://web.archive.org/web/20161020040956/http://extension.uga.edu/publications/detail.cfm?number=B992#title14 . 2016-10-20 . 2016-10-19 . University of Georgia Cooperative Extension, College of Agricultural & Environmental Sciences, Athens, GA . 2012.
  22. Walker JW (1971) Pollen Morphology, Phytogeography, and Phylogeny of the Annonaceae. Contributions from the Gray Herbarium of Harvard University, 202: 1-130.
  23. Cantaluppi . C. J. . 2016-06-01 . The Pawpaw: An Emerging Specialty Crop . live . Journal of the NACAA . 9 . 1 . 2158-9429 . https://web.archive.org/web/20181219134234/https://www.nacaa.com/journal/index.php?jid=582 . 2018-12-19 . 2018-12-19.
  24. Book: Simpson, Michael G . Plant Systematics . October 15, 2019 . 978-0-12-812628-8 . 1322908222. Academic Press. Amsterdam.
  25. Book: Kral, Robert . Magnoliophyta: Magnoliidae and Hamamelidae . . 1997 . 978-0-19-511246-7 . . 3 . New York, NY . Annonaceae . http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220001231.
  26. Web site: 2017 . Asimina triloba (L.) Dunal . live . https://web.archive.org/web/20170427025037/https://plants.usda.gov/core/profile?symbol=ASTR . 27 April 2017 . 23 May 2017 . Plants Database, Natural Resources Conservation Service, US Department of Agriculture.
  27. Tulowiecki . Stephen J . 2021 . Modeling the geographic distribution of pawpaw (Asimina triloba [L.] Dunal) in a portion of its northern range limits, western New York State, USA . Plant Ecology . 222 . 2 . 193–208 . 10.1007/s11258-020-01098-x. 2021PlEco.222..193T . 228809757 .
  28. Horn . Charles N. . December 2015 . A New Hybrid of Asimina (Annonaceae) Based on Morphological and Ecological Data . Castanea . 80 . 4 . 262–272 . 10.2179/15-067 . 85661787 . 0008-7475.
  29. Goodrich . Katherine R . etal . January 2006 . When Flowers Smell Fermented: The Chemistry and Ontogeny of Yeasty Floral Scent in Pawpaw (Asimina triloba: Annonaceae) . International Journal of Plant Sciences . 167 . 1 . 33–46 . 10.1086/498351. 2309906 .
  30. Thein . Leonard B . Azuma . Hiroshi . Kawano . Shoichi . November 2000 . New Perspectives on the Pollination Biology of Basal Angiosperms . International Journal of Plant Sciences . 161 . S6 . S225–S235 . 10.1086/317575. 84852646 .
  31. Web site: Gottsberger . Gerhard . Silberbauer-Gottsberger . Ilse . Basal Angiosperms and Beetle Pollination . 2022-03-31 . XI congreso latinoamericano de botánica e LXV congresso nacional de botânica (2014).
  32. Gottsberger . Gerhard . 2008 . Pollination and Evolution in Neotropical Annonaceae . Plant Species Biology . 14 . 2 . 143–152 . 10.1046/j.1442-1984.1999.00018.x.
  33. Saunders . Richard MK . 2012 . The diversity and evolution of pollination systems in Annonaceae . Botanical Journal of the Linnean Society . 169 . 222–244 . 10.1111/j.1095-8339.2011.01208.x. free .
  34. Book: Moore, Andrew . Pawpaw: In Search of America's Forgotten Fruit . 2015 . Chelsea Green . 978-1-60358-596-5 . Vermont . 4.
  35. Kral . Robert . October 1960 . A Revision of Asimina and Deeringothamnus (Annonaceae) . Brittonia . 12 . 4 . 233–278 . 10.2307/2805119. 2805119 . 1960Britt..12..233K . 35766955 .
  36. Sayers . Thomas DJ . Steinbauer . Martin J . Miller . Rebecca E . April 2019 . Visitor or vector? The extent of rove beetle (Coleoptera: Staphylinidae) pollination and floral interactions . Arthropod-Plant Interactions . 13 . 5 . 685–701 . 10.1007/s11829-019-09698-9. 2019APInt..13..685S . 117745469 .
  37. Web site: Pawpaw Factsheet . Clemson Cooperative Extension . Clemson University . 2023-05-06 .
  38. Web site: Barlow . Connie . 2001 . Anachronistic Fruits and the Ghosts Who Haunt Them . live . https://web.archive.org/web/20130212155715/http://arnoldia.arboretum.harvard.edu/pdf/articles/618.pdf . 12 February 2013 . 5 December 2012 . Harvard University Arboretum.
  39. Janzen, Daniel H., and Paul S. Martin. "Neotropical anachronisms: the fruits the gomphotheres ate." Science 215, no. 4528 (1982): 19-27.
  40. Cook, Robert E. "Attractions of the flesh." Natural History New York, NY 91, no. 1 (1982): 20-24.
  41. Janzen . D. H. . Martin . P. S. . Neotropical Anachronisms: The Fruits the Gomphotheres Ate . Science . American Association for the Advancement of Science (AAAS) . 215 . 4528 . 1982 . 0036-8075 . 10.1126/science.215.4528.19 . 17790450 . 1982Sci...215...19J . 19–27 . 19296719 .
  42. Book: Barlow . Connie . The Ghosts of Evolution: Nonsensical Fruit, Missing Partners and Other Ecological Anachronisms . 2001 . Basic Books . New York . 978-0-465-00551-2 . 51–69.
  43. Abrams . Marc D . Nowacki . Gregory J . 2008 . Native Americans as active and passive promoters of mast and fruit trees in the eastern USA . The Holocene . 18 . 7 . 1123–1137 . 10.1177/0959683608095581 . 2008Holoc..18.1123A . 128836416 . November 19, 2022 . December 19, 2017 . https://web.archive.org/web/20171219113313/http://php.scripts.psu.edu/users/a/g/agl/AbramsNowacki%20Holocene.pdf . dead .
  44. Shipley . Jonathan . 26 April 2022 . The revival of a forgotten American fruit . BBC Travel . 28 April 2022.
  45. Wykoff . M William . March 2009 . On the Natural Distribution of Pawpaw in the Northeast . The Nutshell . 23–32 . April 1, 2022 . April 1, 2022 . https://web.archive.org/web/20220401165724/https://d1wqtxts1xzle7.cloudfront.net/50317044/Pawpaw_in_NE_-_final_version_2-with-cover-page-v2.pdf?Expires=1648835223&Signature=dp9oUQSLuz8TCo7FiqUg8Ep8m~8sA6iUCf~ixn1eeCxiLX~JwBQ8bchpKanOA0KfVTpn9-47VXeV9HI0smBet2si-9-4qAQTkk22zVROTgiy2MUjmJJB0M-cHclQFmI3jNsyHrQQ9U-BjtpiSS4brFfxRDfJdzGBFZrxYtNpc55y~YyqABdOcQwBy0NIloRceG0lvKY~Hd5yPwPM1LA~TJkWdSuReFP015inkLsy3jOkDsLAtyGX4T7qbZyYD-vUfQq5Zv-I2G6i7Vr-XOc9faUmjEeqyldSh27ff-osPbwm4x1su~smJElHVC8qp1m9MUOTFE8V~e1148emC7hY5g__&Key-Pair-Id=APKAJLOHF5GGSLRBV4ZA . dead .
  46. Faber . Sarah W . Pawpaws to the People! . Harvard Crimson . 6 October 2022 .
  47. Web site: Ruegsegger . Ted . My Notes on Pawpaw . 1 May 2023.
  48. Web site: Pawpaw tasting parties aim to educate on Zebra Swallowtail habitat restoration (2022) . Grow Pittsburgh . September 2022 . 1 May 2023.
  49. Web site: Marsden . Gabrielle . Pittsburgh Pawpaw Pathways for Zebra Swallowtail Trails . Wild Ones: Western Pennsylvania Area Chapter . 1 May 2023 . May 1, 2023 . https://web.archive.org/web/20230501141035/https://westernpa.wildones.org/gabrielle-marsden-swallowtail-butterfly/ . dead .
  50. Web site: Barlow . Connie . Pawpaw, Asimina triloba, Habitat: Information for Choosing Sites for Wild-Planting Seeds . TorreyaGuardians . 1 May 2023.
  51. http://www.fs.fed.us/database/feis/plants/tree/asitri/all.html Asimina triloba
  52. B. J. Sampson, J. L. McLaughlin, D. E. Wedge. 2003. PawPaw Extract as a Botanical Insecticide, 2002. Arthropod Management Tests, vol.28, p. L.
  53. Web site: Bilton . Kathy . Pawpaws: A paw for you and a paw for me . live . https://web.archive.org/web/20110718184434/http://www.fred.net/kathy/pawpaws.html . 18 July 2011 . 21 July 2011.
  54. Martin . John M. . Madigosky . Stephen R. . Gu . Zhe-ming . Zhou . Dawei . Wu . Jinn . McLaughlin . Jerry L. . January 1999 . Chemical defense in the zebra swallowtail butterfly, Eurytides marcellus, involving annonaceous acetogenins . . 62 . 1 . 2–4 . 10.1021/np980308s . 9917274.
  55. Marsden . Gabrielle . Plant native pawpaws to bring the butterflies back . The Homepage - Hazelton Initiative . April 2021 . 11 . 3 . 16 . 3 May 2023.
  56. Ames . Guy K. . January 8, 2018 . Pawpaw – A "Tropical" Fruit for Temperate Climates . Small Farms Quarterly . Cornell Small Farms Program . July 11, 2022.
  57. Hosaka . Naomi . Kachi . Naoki . Kudoh . Hiroshi . Stuefer . Josef F. . Whigham . Dennis F. . 2007-11-03 . Patch structure and ramet demography of the clonal tree, Asimina triloba, under gap and closed-canopy . Plant Ecology . 197 . 2 . 219–228 . 10.1007/s11258-007-9372-z . 7969684 . 1385-0237.
  58. Miller . Kathryn M . McGill . Brian J . Compounding human stressors cause major regeneration debt in over half of eastern US forests . Journal of Applied Ecology . 4 March 2019 . 56 . 6 . 1355–1366 . 10.1111/1365-2664.13375 . 92796991 . free . 2019JApEc..56.1355M .
  59. Web site: Matthews . Elizabeth . 21 September 2021 . Pawpaw: Small Tree, Big Impact . National Park Service.
  60. Kain . Morgan . Battaglia . Loretta . Royo . Alejandro . Carson . Walter P. . July 2011 . Over-browsing in Pennsylvania creates a depauperate forest dominated by an understory tree: Results from a 60-year-old deer exclosure . The Journal of the Torrey Botanical Society . 138 . 3 . 322–326 . 10.3159/torrey-d-11-00018.1 . 85648031 . 1095-5674.
  61. Slater . Mitchell . Anderson . Roger C. . Juliano . Steven A. . 2022 . Does the photosynthetic response of Asimina triloba to low light contribute to its competitive advantage in forest understories compared with Acer saccharum and Fraxinus quadrangulata? . The Journal of the Torrey Botanical Society. 150 . 2 . 10.3159/TORREY-D-22-00003.1 . 258815630 .
  62. Sipe . Timothy W . 2023 . Light attenuation by pawpaw (Asimina triloba L.) in a midwestern upland forest . The Journal of the Torrey Botanical Society. 150 . 2 . 10.3159/TORREY-D-22-00016.1 . 258811471 .
  63. Web site: 193.3 Protected native plants . Westlaw . 25 April 2023.
  64. Web site: List of Endangered Plant Species and Plant Species of Concern (New Jersey) . New Jersey Department of Environmental Protection . 25 April 2023.
  65. Web site: Cuerrier . Alain . Pawpaw . The Canadian Encyclopedia . 25 April 2023.
  66. Slater . Mitchell A . Anderson . Rogers C . 2014 . Intensive Selective Deer Browsing Favors Success of Asimina triloba (Paw Paw) a Native Tree Species . Natural Areas Journal . 34 . 2 . 178–187 . 10.3375/043.034.0207. 52834948 .
  67. Book: Little, Elbert . Atlas of United States Trees . United States Department of Agriculture . 1978.
  68. Web site: Jones . Snake C. . Layne . Desmond R. . 1997 . Cooking with Pawpaws . Kentucky State University.
  69. Robles-Diaz-de-Leon . Luisa Fernanda . Nava-Tudela . Alfredo . 1998 . Playing with Asimina triloba (pawpaw): A species to consider when enhancing riparian forest buffer systems with non-timber products . Ecological Modelling . 112 . 2–3 . 169–193. 10.1016/S0304-3800(98)00078-7 . 1998EcMod.112..169F .
  70. etal. Miller . Kathryn M . Overabundant deer and invasive plants drive widespread regeneration debt in eastern United States national parks . Ecological Applications . March 2023 . 33 . 4 . e2837 . 10.1002/eap.2837 . 36890590 . 257425694 . free . 2023EcoAp..33E2837M .
  71. Slater . Mitchell A . Anderson . Roger C . Intensive Selective Deer Browsing Favors Success of Asimina triloba (Paw Paw) a Native Tree Species . Natural Areas Journal . April 2014 . 34 . 2 . 178–187 . 10.3375/043.034.0207 . 52834948 .
  72. News: House . Kelly . 3 May 2021 . As northern Michigan warms, scientists bring tree seedlings from the south . Michigan Bridge . live . 21 July 2021 . https://web.archive.org/web/20210504180229/https://www.bridgemi.com/michigan-environment-watch/northern-michigan-warms-scientists-bring-tree-seedlings-south . 4 May 2021.
  73. Web site: 2020-05-01 . Way Down Yonder in the Paw-Paw Patch . 2022-06-19 . Smithsonian Gardens . en.
  74. Book: Moore, Andrew . Pawpaw: In Search of America's Forgotten Fruit . 2015 . Chelsea Green Publishing . 9781603585965 . White River Junction, Vermont . November 28, 2020.
  75. Web site: Ahuja . Akshay . September 10, 2015 . Rediscovering The Pawpaw . live . https://web.archive.org/web/20161012165400/http://www.cincinnatimagazine.com/forkopolisblog/rediscovering-the-pawpaw/ . October 12, 2016 . May 29, 2020 . cincinnatimagazine.com.
  76. News: Damrosch . Barbara . 8 Sep 2011 . Return of the Native? Pawpaws' Proponents . The Washington Post (Local Living, p.9).
  77. News: Kane . Roni . 'Nothing as dramatic as the pawpaw': Ann Arbor pawpaw farmer Marc Boone retraces memories through orchard . Michigan Daily . 26 October 2022.
  78. Web site: Locals explore the culinary potential of pawpaw . October 9, 2021 .
  79. etal. Brannan . Robert G . Phytochemical analysis of ten varieties of pawpaw (Asimina triloba [L.] Dunal) fruit pulp ]. Food Chemistry . February 2015 . 158 . 656–661 . 10.1016/j.foodchem.2014.07.018 . 25172760 .
  80. Harris . Grant G . Brannan . Robert G . An Evaluation of Antioxidant Compounds, Reducing Potential, and Radical Scavenging of Pawpaw (Asimina tribloba) Fruit Pulp from Different Stages of Ripeness . Food Science and Technology . 2009 . 42 . 1 . 275–279 . 10.1016/j.lwt.2008.05.006 .
  81. Potts . L. F. . Luzzio . F. A. . Smith . S. C. . Hetman . M. . Champy . P. . Litvan . I. . 2012 . Annonacin in Asimina triloba fruit: Implication for neurotoxicity . live . NeuroToxicology . 33 . 1 . 53–8 . 10.1016/j.neuro.2011.10.009 . 22130466 . 2012NeuTx..33...53P . https://web.archive.org/web/20161005044035/https://neurosciences.ucsd.edu/centers/movement-disorders/Documents/Litvan%20Article%20Annonacin.pdf . 2016-10-05 . 2016-08-18.
  82. Kim . Eun Jung . Suh . Kyung Mi . Kim . Dal Hwan . Jung . Eun Joo . Seo . Chang Seob . Son . Jong Keun . Woo . Mi Hee . McLaughlin . Jerry L. . February 2005 . Asimitrin and 4-hydroxytrilobin, new bioactive annonaceous acetogenins from the seeds of Asimina triloba possessing a bis-tetrahydrofuran ring . . 68 . 2 . 194–197 . 10.1021/np040184l . 15730242.
  83. Zhao . Geng-Xian . Laura R. . Miesbauer . Smith . David L. . McLaughlin . Jerry L. . June 1994 . Asimin, asiminacin, and asiminecin: novel highly cytotoxic asimicin isomers from Asimina triloba . . 37 . 13 . 1971–1976 . 10.1021/jm00039a009 . 8027979.
  84. Web site: Sorten der Indianerbanane . live . https://web.archive.org/web/20200610154306/https://www.pawpawschule.de/deutsch-1/sorten-der-indianerbanane/ . 2020-06-10 . 2020-06-10 . Florians Pawpawschule - Asimina triloba . de.
  85. Web site: Table 3. Pawpaw Cultivars . pawpaw.kysu.edu . Kentucky State University.
  86. Web site: Pomper . Kirk W. . Crabtree . Sheri B. . Lowe . Jeremiah D. . January 21, 2009 . 2009 Pawpaw Cultivars and Grafted Tree Sources . live . https://web.archive.org/web/20190922044507/https://kysu.edu/academics/cafsss/pawpaw/2009-pawpaw-cultivars-and-grafted-tree-sources/ . September 22, 2019 . September 22, 2019 . Kentucky State University.
  87. Web site: etal . Jones . Snake C . Pawpaw Planting Guide . kysu.edu . Kentucky State University Cooperative Extension Program . 29 April 2023.
  88. https://www.kysu.edu/academics/college-acs/school-of-ace/pawpaw/index.php Kentucky State University | Pawpaw
  89. Web site: Kaiser . Cheryl . Ernst . Matt . July 2018 . Pawpaw . live . https://web.archive.org/web/20190715075104/http://www.uky.edu/ccd/sites/www.uky.edu.ccd/files/pawpaw.pdf . 2019-07-15 . 2019-09-22 . University of Kentucky, College of Agriculture, Food and Environment, Cooperative Extension Service.
  90. Web site: Pomper . Kirk W. . Layne . Desmond R. . Peterson . R. Neal . 1999 . The Pawpaw Regional Variety Trial . live . https://web.archive.org/web/20150414071607/http://www.hort.purdue.edu/newcrop/proceedings1999/v4-353.html . 2015-04-14 . 2019-09-26 . hort.purdue.edu.
  91. Web site: USDA National Clonal Germplasm Repository for Asimina spp. at KSU, Slide 4 . live . https://web.archive.org/web/20190926210916/https://kysu.edu/academics/cafsss/pawpaw/usda-national-clonal-germplasm-repository-for-asimina-spp-at-ksu/ . 2019-09-26 . 2019-09-26 . Kentucky State University.
  92. Web site: PawPaw . live . https://web.archive.org/web/20190921190116/https://kysu.edu/academics/cafsss/pawpaw/ . 2019-09-21 . 2019-09-22 . Kentucky State University.
  93. etal . Tran . Kevin . Annonacin and Squamocin Contents of Pawpaw (Asimina triloba) and Marolo (Annona crassiflora) Fruits and Atemoya (A. squamosa × A. cherimola) Seeds . Biological Trace Element Research . June 2021 . 199 . 6 . 2320–2329 . 10.1007/s12011-020-02320-7 . 32761515 . 2021BTER..199.2320T . 220980817 .
  94. Web site: The 15th Annual Ohio Pawpaw Festival . live . https://web.archive.org/web/20130731084314/http://www.ohiopawpawfest.com/ . 2013-07-31 . 2013-08-09 . Ohio Pawpaw Festival.
  95. Web site: Pawpaw . live . https://web.archive.org/web/20110720235418/http://www.crfg.org/pubs/ff/pawpaw.html . 20 July 2011 . 15 July 2011 . California Rare Fruit Growers.
  96. Templeton . Susan B. . Marlette . Martha . Pomper . Kirk W. . Jones . Snake C. . 2003-01-01 . Favorable Taste Ratings for Several Pawpaw Products . HortTechnology . en-US . 13 . 3 . 445–448 . 10.21273/HORTTECH.13.3.0445 . 1943-7714. free .
  97. Web site: Asimina triloba - Plant Finder . 2023-04-27 . www.missouribotanicalgarden.org.
  98. Huang . Kuan-Ming . Guan . Zhengfei . Hammami . AbdelMalek . October 2022 . The U.S. Fresh Fruit and Vegetable Industry: An Overview of Production and Trade . Agriculture . en . 12 . 10 . 1719 . 10.3390/agriculture12101719 . 2077-0472 . free .
  99. Web site: 2000 . Propagation of Pawpaw (Asimina triloba) . 17 May 2016 . International Plant Propagators' Society. Combined Proceedings of Annual Meetings.
  100. Web site: Chapter: Propagation, The Pawpaw M. Brett Callaway. Originally published as a booklet in 1990 by Kentucky State University, edited and converted to web format in 1998 by Snake C. Jones . pawpaw.kysu.edu . Kentucky State University.
  101. Web site: Asimina triloba 'Sunflower' (Sunflower Pawpaw) North Carolina Extension Gardener Plant Toolbox . 2023-04-27 . plants.ces.ncsu.edu.
  102. Web site: State Nurseries and Tree Seedlings - Kentucky Energy and Environment Cabinet . live . https://web.archive.org/web/20190924184155/https://eec.ky.gov/Natural-Resources/Forestry/state-nuseries-and-tree-seedlings/Pages/default.aspx . 2019-09-24 . 2019-09-22 . eec.ky.gov.
  103. Web site: University of Kentucky Cooperative Extension Service . Asimina triloba (Pawpaw) . State of Kentucky . 27 April 2023.
  104. Web site: Paw Paw Tunnel . https://web.archive.org/web/20111006175828/http://pawpawwv.com/local-attractions/paw-paw-tunnel . October 6, 2011 . 15 July 2011 . Town of Paw Paw, West Virginia.
  105. Web site: RRHX - Railroad History Time Line - 1860 . dead . https://web.archive.org/web/20110723193351/http://www.michiganrailroads.com/RRHX/Timeline/1860s/TimeLine1860sBackUp.htm . 2011-07-23 . 6 August 2011 . RRHX: Railroad History of Michigan.
  106. Zeimetz, Lisa. "Stephen Wright House," (PDF), National Register of Historic Places Nomination Form, 1 April 2005, HAARGIS Database, Illinois Historic Preservation Agency. Retrieved September 21, 2019.
  107. Book: History of Miami County, Indiana: From the Earliest Time to the Present . Brant & Fuller . 1887 . 536 . paw-paw..
  108. Book: Hess, Cameron M. Ludwick & Blair Thomas . My Old Kentucky Road Trip: Historic Destinations & Natural Wonders . 30 March 2015 . Arcadia Publishing . 978-1-62619-816-6 . 168.
  109. Web site: Sullivan County, Missouri Place Names, 1928-1945 | The State Historical Society of Missouri . live . https://web.archive.org/web/20190921182949/https://collections.shsmo.org/manuscripts/ramsay/ramsay_sullivan.html . 2019-09-21 . 2019-09-21 . collections.shsmo.org.
  110. Web site: NATIONAL PAWPAW DAY - Third Thursday in September . August 2, 2019 . live . https://web.archive.org/web/20190921190019/https://nationaldaycalendar.com/national-pawpaw-day-third-thursday-in-september/ . 2019-09-21 . 2019-09-21 . National Day Calendar.
  111. Web site: Third Thursday Thing Program . live . https://web.archive.org/web/20190921190018/https://kysu.edu/academics/cafsss/cooperative-extension/third-thursday-thing/ . 2019-09-21 . 2019-09-21 . kysu.edu . Kentucky State University.
  112. Web site: The 'Third Thursday Thing': Eleven Years and Going Strong . live . https://web.archive.org/web/20190921190017/https://kysu.edu/academics/cafsss/organic-agriculture-working-group/the-third-thursday-thing-eleven-years-and-going-strong/ . 2019-09-21 . 2019-09-21 . kysu.edu . Kentucky State University.
  113. [Ohio Revised Code]
  114. Web site: Ohio Pawpaw Festival . live . https://web.archive.org/web/20200104140941/https://ohiopawpawfest.com/ . 2020-01-04 . 2020-05-11 . ohiopawpawfest.com.
  115. Web site: 15 August 2016 . Pawpaw Folk Festival set for Aug. 20 at the Blue Ball Barn . live . https://web.archive.org/web/20161202225252/http://news.delaware.gov/2016/08/15/pawpaw-folk-festival-set-for-aug-20-at-the-blue-ball-barn/ . 2 December 2016 . 9 December 2016.
  116. Burke . Horace R. . Hodges . Ronald W. . 1971-07-23 . The Moths of America North of Mexico, including Greenland. Fascicle 21 . The Southwestern Naturalist . 16 . 1 . 129 . 10.2307/3670112 . 3670112 . 0038-4909.
  117. Web site: Missouri Revisor of Statutes - Revised Statutes of Missouri, RSMo, Missouri Law, MO Law, Joint Committee on Legislative Research . 2021-04-02 . revisor.mo.gov.