Curculio sayi

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Curculio sayi
Curculio sayi side.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Coleoptera
Family: Curculionidae
Genus: Curculio
Species:
C. sayi
Binomial name
Curculio sayi
(Gyllenhal, 1836)
Synonyms [1]
  • Balaninus acuminatus Casey, 1910
  • Balaninus algonquinus Casey, 1910
  • Balaninus auriger Casey, 1910
  • Balaninus macilentus Casey, 1910
  • Balaninus mollis Casey, 1910
  • Balaninus perexilis Casey, 1910
  • Balaninus setosicornis Casey, 1910
  • Balaninus sparsus Gyllenhal, 1836
  • Balaninus strigosus Casey, 1910

Curculio sayi, the small or lesser chestnut weevil, is a species of true weevil in the family of beetles known as Curculionidae. [1] [2] [3]

Contents

The lesser chestnut weevil is found in North America. [1] The distribution of this species extends from Canada and Massachusetts to North Carolina, Tennessee, and Ohio, and probably farther westward. This weevil is highly host-specific. It has only been observed to feed and oviposit on the genus Castanea (chestnut and chinquapin). [4]

Before the arrival of the chestnut blight, small chestnut weevils and the greater Curculio caryatrypes were prominent pests of the American chestnut crop. [5] Reports from the early 1900s mentioned that large losses in American chestnut production occurred due to infestation by Curculio larvae. [6] American chestnut crop infestation rates between 50% and 75% were considered normal. [7] With the spread of the chestnut blight in American chestnut trees, the strictly host specific Curculio caryatrypes may have become extinct. [8] Curculio sayi is less host specific and reproduces in the chestnuts of other species of Castanea. [5]

If left unchecked, weevil populations in an orchard can develop rapidly, reaching high levels of infestation in as little as two years. [9] Infested nuts are less likely to germinate, if at all and nut damage affects chestnut seedling growth. The rate of nuts weevil infestation may vary between years, locations, cultivars, and even individual trees, burrs and nuts. [10] [11]

Similar weevil species

An evolved specialized life style among chestnut weevils and other insect taxa is that female adults bore into specific plant tissue to oviposit. These plant tissues surround the weevil offspring while the offspring is feeding and developing. [12] How this specialized life style could evolve to single host specificity is under scientific debate.

In Europe, Curculio elephas may occupy a similar ecological niche as Curculio sayi in North America. Curculio elephas is not as host specific as Curculio sayi in North America, as it oviposits in chestnuts and acorns of some oak species. [13] For Curculio elephas, French research has shown that the chestnut infestation rate of sparsely spiky burrs (90%) and densely spiky burrs (2%) can show great variation at the same location and year. [13] Chestnut weevils laid more eggs in the lower half of a chestnut close to the hilum. Close to the hilum can be a burr area less spiky. Weevils deposited an egg into about one of four rostrum borings. [14] Other research results suggest that chestnut weevil females avoid laying an egg into chestnuts of a certain development stage. [15] French research found that, Curculio elephas females oviposited on average 20 eggs into chestnuts per life time/season. Further, the statistical chestnuts infestation distribution of a particular tree was zero-inflated. [15] A zero-inflated model deals with statistical situations where there is an excessive number of chestnuts with zero weevils. Most of the weevil infested chestnuts were found in the South and West orientation of a tree canopy. The timing of burr opening and the timing of nut drop apparently was not affected by weevil infestation of chestnuts.

In Hungary, most of the adult weevil activity in chestnut trees was noted on warm nights between 6pm and 10pm. Light traps at 12 meter (40 ft) height caught the most adult weevils. [13] Other research on pecan weevils' ability to fly suggests warm temperature dependency and sex differences. At a temperature range in the mid 80'F (27C) to mid 90'F (35C), female pecan weevils were more capable of flying high into the tree canopy. By comparison more male pecan weevils than female pecan weevils were observed crawling to the closest pecan tree trunk. [16] In plum curculio at 68F (20C) air temperature crawling behavior changed to flying behavior. [17]

In Kentucky and Indiana big brown bats were described as specialist predators of night flying beetles such as weevils. [18] [19]

In plum curculio the period from adult soil emergence to mating is 6–17 days. [20]

Curculio elephas exhibits capital breeding traits. Adults carry developed eggs upon soil emergence and apparently may not need to feed before egg laying. [21] If Curculio sayi exhibits similar behaviors to other weevil species has not been researched yet.

Both the European and North American chestnut weevil species exhibit an optionally extended life cycle. A prolonged or repeated diapause of individual larvae can result in individual life cycle completion of one, two, three or even four years. [22]

In Curculio elephas a reported soil emergence from a single weevil larvae generation underneath oak tree canopy varied. Reported emergence rates were 66% the first year, 30% the second year and 4% the third year. [23] Under controlled conditions, adult survival performance was similar between individuals emerging after one and two years. [11] [22]

A hypothesis is that diapause variation may be the response to seasonal environmental survival challenges. In a dry summer with hardened soil, one quarter to three quarter of the developed adults may not be able to soil emerge and thus perish. Hardened soils challenged adult emergence of the larger female weevils at a higher rate than the smaller male weevils. A season's environmental conditions may affect the sex ratio of surviving adults. [11]

The mechanism for diapause variations is proposed to be bet hedging and not genotypic differences within a population. [24]

Hazelnuts are affected by several different weevil species including Curculio dieckmanni (Faust), Curculio nucum L., Curculio obtusus Gibson, and Curculio occidentis . [25]

External morphology

The average length of the body alone is about 1⁄4 inch (6.4 mm). [6]

Dorsal view Curculio sayi dorsal.jpg
Dorsal view

Males are approximately 10 mm in overall length with comparatively shorter rostrums (slender snouts). Females are approximately 15 mm in overall length with comparatively longer rostrums.

In chestnut weevils, the long rostrum is considered to be a key adaptation measure. A rostrum helps bypass the sharp spines of a chestnut burr and the excavating action of a rostrum before egg laying avoids the drying of eggs later on. As a secondary benefit, the host's defensive burr facilitates protected egg hatching in the hosts from predators or parasitoids. [26] In the small chestnut weevil the first segment of the antenna funicule is longer than the second.

Life cycle

First soil emergence of adults may vary from May, June to July, according to locality and season - growing degree days. In Mid Missouri adults started emerging from the soil in May and June, stopped emerging in July and started emerging again in late August until October. [27] In New York State, the adult population reached it peak in mid October at 2,500 growing degree days. [28]

Adults, from a single generation of larvae, may emerge from the soil over multiple years. Seasonal population dynamics may vary in different climate zones. [28] [29] [30] Male and female beetles emerge from the soil at similar times and at similar numbers. Dry and hardened soil conditions in summer and early fall may slow soil emergence and affect in-soil survival rates. [27]

Development

A mated female weevil uses her long snout to chew a hole in the side of the nut shell or lining. Research on a similar chestnut weevil (Curculio elephas) in Europe suggest that egg laying may occur into selected chestnuts and not in random chestnuts. Reportedly, Curculio elephas was non-selective about what burr to approach. It was also non-selective to burrs in terms of pollinated chestnuts. Egg laying occurred at the same rate if a burr had one, two or three viable chestnuts. Research results suggests that European chestnut weevils select a specific nut quality for egg laying. Curculio elephas also did not appear to chemically mark a nut where it has deposited an egg, nor does it appear to sense in other ways if a nut already has an egg deposited. [11] If this egg laying behavior is similar in Curculio sayi has not been researched. If Curculio sayi taste tests nut meat before egg laying or how many nuts the weevils probe before an egg is laid has not been researched. Clean adult weevil chew holes are usually too small to visually identify on the nut shell. Only when an adult weevil chew hole starts a mold infection, may weevil chewing activity become visually identifiable on the nut shell surface.

The nutrient quantity in a viable chestnut can support development of several larvae (up to a dozen) at the same time.

Weevil eggs hatch in five to seven days. When hatched, the large, white, legless grubs (larvae) feed on the tissue of the growing chestnut kernels. [6] When the larvae reach their last of four instar inside the chestnut, they chew a 1/8" hole in the chestnut shell and emerge. Most larvae emerge and fall to the ground while the chestnut is still in the tree.

Peak emergence of larvae from fallen chestnuts occurs at six days post harvest and drops to low emergence levels by day 16 post harvest. A few larvae may still emerge from infested chestnuts more than four weeks post harvest. [28] Refrigeration of harvested chestnuts or cold temperatures slows grub development and emergence.

Most nut-emerged larvae burrow 7–15 cm below the soil line. [27] There they build a soil chamber. They pupate after several months (up to 18 months or longer) and remain in their soil chamber for at least one season. [27]

Infestation controls

Cultural control through orchard sanitation may be a main step in managing chestnut weevil populations. [30] Underground larval mortality of the European chestnut weevil was reported to be greater than 50%. Predation by mammals or invertebrates in an orchard may increase mortality rates. [11] Natural mortality rates for Curculio sayi have not been researched yet.

Chemical control via insecticides of the adults is possible. Chemical control approaches require scouting and positive identification in August and September, and possibly weekly application of broad spectrum insecticides to the top of the orchard canopy. [29] [30]

Biological control of the small chestnut weevil larvae by applying entomopathogenic fungi and entomopathogenic nematodes to the soil may be possible. The effectiveness of entomopathogenic nematodes may take two to three years of soil applications before nuts and weevil larvae fall. [31]

Postharvest heat treatment of collected chestnuts can stop development of weevil eggs and small larvae without destroying the viability of the nut. Soaking for 20 minutes in hot water maintained at 120 °F (49 °C) is an effective method. [32]

Weevil larvae frass in the chestnut is associated with Aspergillus fungi which produce the diarrheagenic toxin emodin. [33]

Scouting

Scouting for soil emerging adults is somewhat effective with a dark colored pyramid trap. These traps should be set one per acre well before chestnut bloom occurs and checked twice a week.

The most effective method of identifying weevil presence within an orchard is via limb-tapping over a light colored sheet. Weevils drop when a branch is jarred. [29] Adult weevils are considered poor dispersers with an average flight distance of 220 m. [34]

Related Research Articles

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<span class="mw-page-title-main">Wheat weevil</span> Species of beetle

The wheat weevil, also known as the grain weevil or granary weevil, is an insect that feeds on cereal grains, and is a common pest in many places. It can cause significant damage to harvested stored grains and may drastically decrease crop yields. The females lay many eggs and the larvae eat the inside of the grain kernels.

<span class="mw-page-title-main">Vine weevil</span> Species of beetle

The black vine weevil is an insect native to Europe but common in North America as well. It is a pest of many garden plants.

<i>Chrysolopus spectabilis</i> Species of beetle

Chrysolopus spectabilis is a species of weevil found in south-eastern Australia. It was discovered during James Cook's first voyage, and became one of the first insects to be described from Australia. The weevil measures up to 25 mm (1.0 in) long and includes distinctive metallic green and black scales. It is found only on 28 species of the plant genus Acacia.

<i>Curculio</i> Genus of beetles

Curculio is a genus of weevils belonging the family Curculionidae and subfamily Curculioninae. Members of the genus are commonly referred to as acorn weevils or nut weevils as they infest the seeds of trees such as oaks and hickories. The adult female weevil bores a tiny hole in the immature nut to lay her eggs, which then hatch into legless grubs. In autumn, the grubs bore holes through the shells from the inside to emerge into the soil where they may live for a year or two before maturing into adults.

<i>Rhynchophorus ferrugineus</i> Pest weevil on palm (oil, coconut, date)

The palm weevil Rhynchophorus ferrugineus is one of two species of snout beetle known as the red palm weevil, Asian palm weevil or sago palm weevil. The adult beetles are relatively large, ranging between 2 and 4 centimetres long, and are usually a rusty red colour—but many colour variants exist and have often been classified as different species. Weevil larvae can excavate holes in the trunks of palm trees up to 1 metre (3.3 ft) long, thereby weakening and eventually killing the host plant. As a result, the weevil is considered a major pest in palm plantations, including the coconut palm, date palm and oil palm.

<i>Curculio nucum</i> Species of beetle

Curculio nucum, the nut weevil, is a medium-sized beetle, with an especially elongated snout, characteristic of the Curculionini tribe of the weevil family (Curculionidae). Its larvae develop in hazel nuts Corylus avellana, being a serious pest in hazelnut orchards. It occurs in most of Europe, from south Sweden, Finland and Great Britain to the Mediterranean.

<i>Curculio glandium</i> Species of weevil

Curculio glandium, commonly known as the acorn weevil, is a species of European carpophagus weevil in the genus Curculio, the acorn and nut weevils. It eats by a rostrum, an elongated snout, that is used for piercing.

<i>Anthonomus eugenii</i> Species of beetle

Anthonomus eugenii is known as the pepper weevil. This beetle feeds and lays eggs on plants in the genus Capsicum and a few species in the genus Solanum. A. eugenii is native to Mexico, however, it is an important pest of Capsicum in Florida, Puerto Rico, and Central America.

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<i>Curculio caryae</i> Species of beetle

The pecan weevil, Curculio caryae is an obligate feeder on the nuts of North American hickories and pecans, most widely recognized as an economically important pest of the pecan, Carya illinoinensis. It has also been observed to infest one Juglans species, the Persian walnut, Juglans regia.

<i>Sternochetus mangiferae</i> Species of beetle

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<i>Curculio elephas</i> Species of beetle

Curculio elephas is a species of beetle in the family Curculionidae, the true weevils. It is known commonly as the chestnut weevil. It is a serious pest of chestnut in Europe.

<i>Bruchus rufimanus</i> Species of beetle

Bruchus rufimanus, commonly known as the broadbean weevil, broadbean beetle, or broadbean seed beetle is a leaf beetle which inhabits crops and fields, as well as some homes. It is a pest of faba beans. The adult beetles feed on pollen, while their larvae tunnel in seeds destroying crops and moving on to new ones once they dry out. The adult beetle, being one of the biggest of its genus, ranges from 3 to 5 mm in length.

<i>Hypera postica</i> Species of beetle

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<i>Hypera nigrirostris</i> Species of beetle

Hypera nigrirostris, commonly known as the lesser clover leaf weevil, is a species of weevil that is native to Europe and northern Africa and has been introduced to North America and Japan. Both adults and larvae feed on red clover and other plants in the family Fabaceae.

<i>Sitona lineatus</i> Species of beetle

Sitona lineatus, commonly known as the pea leaf weevil is a species of weevil with a Palearctic distribution. It is a common pest of beans, peas, and other plants in the family Fabaceae. Adult beetles of S. lineatus measure 3.4-5.3 mm in length. They are characterized by a series of colored scales arranged in alternating lines (striae) on the elytra; it is from this characteristic where the species gets its name lineatus meaning 'lined' or 'striped'. The head and pronotum also have fine pointed setae amongst the scales. The antennae are clubbed, pointed and preceded by 7 segments. The femora is dark, but tibiae and tarsi are red. As a member of Order Coleoptera (beetles) their forewings are modified to form hardened covers over the thorax and abdomen, with the hindwings for flight underneath.

Trichobaris trinotata, commonly known as the potato stalk borer, is a species of weevil in the family Curculionidae. It is found in North America where it is a pest of potato plants, the larvae tunnelling inside their stems.

Listronotus oregonensis, the carrot weevil, is a species of weevil in the beetle family Curculionidae. It is found in North America.

<i>Conotrachelus posticatus</i> Species of beetle

The Conotrachelus posticatus is a species of true weevil within the beetle family Curculionidae. C. posticatus is found in North America. It is on average 3.7–5 mm (0.15–0.20 in) long, and it is present in North America all the way to Panama. This species of Conotrachelus breeds in acorns; as a result, its larvae are found within acorns and their larval diet includes acorns. Their growing presence within oak trees has been studied and their effect on oak trees shows that they attack these trees by destroying the seeds within the tree. At times, the seeds can be found to be partially damaged, and requires further studying to understand the activity of the species in relation to oak trees.

References

  1. 1 2 3 "Curculio sayi Report". Integrated Taxonomic Information System. Retrieved 2018-04-26.
  2. ↑ "Curculio sayi species details". Catalogue of Life. Retrieved 2018-04-26.
  3. ↑ "Curculio sayi Species Information". BugGuide.net. Retrieved 2018-04-26.
  4. ↑ Keesey, Ian W.; Barrett, Bruce A.; Lin, Chung-ho; Lerch, Robert N. (2012). "Electroantennographic Responses of the Small Chestnut Weevil Curculio sayi (Coleoptera: Curculionidae) to Volatile Organic Compounds Identified From Chestnut Reproductive Plant Tissue". Environmental Entomology. 41 (4). Oxford Academic: 933–940. doi: 10.1603/EN12065 .
  5. 1 2 Anderson, Robert S. (2017-02-02). "Co-Extinction The Case of American Chestnut and the Greater Chestnut Weevil (Curculio caryatrypes)". Nature.
  6. 1 2 3 Chittenden, Frank Hurlburt, ed. (1908). The Nut Weevils Yearbook of the Department of Agriculture. US Department of Agriculture, Bureau of Entomology.
  7. ↑ Brooks, F.E.; Cotton, R.T., eds. (1929). The Chestnut Curculios. US Department of Agriculture.
  8. ↑ Charles, Michael; McKenna, Duane (2023-12-26). "Did the Functional Extinction of the American Chestnut, Castanea dentata, Result in the Extinction of the Greater Chestnut Weevil, Curculio caryatrypes?". Northeastern Naturalist. 30 (4): 511–520.
  9. ↑ Johnson, W.T. (1956). On the Biology and Control of the North American Chestnut Weevils (Ph.D. thesis). University of Chicago.
  10. ↑ Dalgeish, Harmony J; Shukle, John T; Swihart, Robert K. (2012). "Weevil seed damage reduces germination and seedling growth of hybrid American chestnut". Canadian Journal of Forest Research. 42 (6): 1107–1114. Bibcode:2012CaJFR..42.1107D. doi:10.1139/x2012-067.
  11. 1 2 3 4 5 Menu, F; Debouzie, D (1995). "Larval development variation and adult emergence in the chestnut weevil Curculio elephas Gyllenhal (Col., Curculionidae)". Journal of Applied Entomology. 119 (1–5): 279–284. doi:10.1111/j.1439-0418.1995.tb01286.x. S2CID   85857060.
  12. ↑ Tooker, John F.; Giron, David (2020). "The Evolution of Endophagy in Herbivorous Insects". Frontiers in Plant Science. 11. doi: 10.3389/fpls.2020.581816 . PMC   7673406 . PMID   33250909.
  13. 1 2 3 Buerges, G; Gal, T (1981). "Zur Verbreitung und Lebensweise des Kastanienruesslers (Curculio elephas Gyll., Col.: Curculionidae) in Ungarn". Zeitschrift für Angewandte Entomologie. 91 (1–5). Blackwell Verlag GmbH: 375–382. doi:10.1111/j.1439-0418.1981.tb04492.x.
  14. ↑ Coutin, Remi; Dusaussoy, G (1956). "Etude expérimentale de la ponte de Balaninus elephas Gyll. sur les châtaignes [Coll. Curculionidae]". Bulletin de la Société entomologique de France. 61 (3–4): 62–66. Bibcode:1956AnSEF..61...62C. doi:10.3406/bsef.1956.18824. S2CID   230144693.
  15. 1 2 Desouhant, Emmanuel; Debouzie, Domitien (1998). "Oviposition pattern of phytophagous insects: on the importance of host population heterogeneity" (PDF). Oecologia. 114 (3): 382–388. Bibcode:1998Oecol.114..382D. doi:10.1007/s004420050461. PMID   28307782. S2CID   8909788.
  16. ↑ Raney, Harley G. (1967). FLIGHT HABITS OF THE PECAN WEEVIL, CURCULIO CARYAE (B.S. thesis). Oklahoma State University.
  17. ↑ Prokopy, Ronald J; Wirth, Catherine B.; Leskey, Tracy C. (1999). "Movement of plum curculio adults toward host trees and traps: Flight versus walking". Entomologia Experimentalis et Applicata. 91 (3): 385–392. doi:10.1023/A:1003626613823 (inactive 18 December 2024).{{cite journal}}: CS1 maint: DOI inactive as of December 2024 (link)
  18. ↑ Asher, Sarah Elizabeth (2012). A Dietary Study of big brown (Eptesicus fuscus) and northern bats (Myotis septentrionalis) in Western Kentucky (M.S. thesis). Eastern Kentucky University . Retrieved 2023-10-27.
  19. ↑ Brack, Virgil; Whitaker, John O (2004). "BATS OF THE NAVAL SURFACE WARFARE CENTER AT CRANE, INDIANA". Proceedings of the Indiana Academy of Science. 113 (1pages= 66-75). Indiana University.
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  21. ↑ Pelisson, Pierre-Francois; Bel-Venner, Marie-Claude; Rey, Benjamin; Burgevin, Lorraine; Martineau, Francois; Fourel, Francois; Lecuyer, Christophe; Menu, Frederic; Venner, Samuel (2011). "Contrasted breeding strategies in four sympatric sibling insect species: when a proovigenic and capital breeder copes with a stochastic environment". Functional Ecology. 26 (1): 198–206. doi: 10.1111/j.1365-2435.2011.01925.x . S2CID   86321833.
  22. 1 2 Soula, Bertrand; Menu, Frederic (2005). "Extended life cycle in the chestnut weevil: prolonged or repeated diapause?". Entomologia Experimentalis et Applicata. 115 (2): 333–340. Bibcode:2005EEApp.115..333S. doi:10.1111/j.1570-7458.2005.00281.x. ISSN   0013-8703. S2CID   85115061.
  23. ↑ Pelisson, Pierre-Francois; Bernstein, Carlos; Francois, Debias; Menu, Frederic; Venner, Samuel (2013). "Dispersal and dormancy strategies among insect species competing for a pulsed resource". Ecological Entomology. 38 (5): 470–477. Bibcode:2013EcoEn..38..470P. doi:10.1111/een.12038. S2CID   84087081.
  24. ↑ Menu, F (1993). "Strategies of emergence in the chestnut weevil Curculio elephas (Coleoptera: Curculionidae)". Oecologia. 96 (3): 383–390. Bibcode:1993Oecol..96..383M. doi:10.1007/BF00317509. PMID   28313654. S2CID   32907296.
  25. ↑ Shanovich, Hailey; Aukema, Brian (2022). "The Biology, Ecology, and Management of the Hazelnut-Feeding Weevils (Curculio spp.) (Coleoptera: Curculionidae) of the World". Journal of Integrated Pest Management. 13 (1): 16. doi: 10.1093/jipm/pmac008 .
  26. ↑ Anderson, Robert S. (1995). "An evolutionary perspective on diversity in Curculionoidiae". Memoir Entomology Society Washington. 14: 103–114.
  27. 1 2 3 4 Keesey, Ian W.; Barrett, Bruce (2008). "Seasonal Occurrence and Soil Distribution of the Lesser Chestnut Weevil, Curculio sayi (Coleoptera: Curculionidae) in Mid-Missouri". Journal of the Kansas Entomological Society. 81 (4): 345–354. doi:10.2317/JKES804.08.1. S2CID   85604543.
  28. 1 2 3 Filgueiras, C.C.; Willett, D.S. (2022). "Phenology and Monitoring of the Lesser Chestnut Weevil (Curculio sayi)". Insects. 13 (8): 713. doi: 10.3390/insects13080713 . PMC   9409741 . PMID   36005338.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  29. 1 2 3 Lizotte E. (2014). "Chestnut Weevil: A Potential Pest of Michigan Chestnuts". Michigan State University. Retrieved 2023-10-13.
  30. 1 2 3 Lizotte E. (2020). "Managing chestnut weevil in Michigan in 2020". Michigan State University. Retrieved 2023-10-13.
  31. ↑ Filgueiras, C.C.; Willett, D.S. (2022). "The Lesser Chestnut Weevil (Curculio sayi): Damage and Management with Biological Control Using Entomopathogenic Fungi and Entomopathogenic Nematodes". Insects. 13 (12): 1097. doi: 10.3390/insects13121097 . PMC   9788462 . PMID   36555007.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  32. ↑ Guyer, D. Chestnut Growers Inc., 2018
  33. ↑ Wells, J.M.; Cole, R.J.; Kirksey, J.W (1975). "Emodin, a toxic metabolite of Aspergillus Wentii Isol. Weevil-Damaged Chestnuts". Applied Microbiology. 30 (1): 26–28. doi:10.1128/am.30.1.26-28.1975. PMC   187107 . PMID   1147616.
  34. ↑ Keesey, Ian W. (2007). The seasonal occurrence, soil distribution, and flight characteristics of Curculio sayi (Coleoptera: Curculionidae) in mid-Missouri (M.S. thesis). University of Missouri, Columbia, Missouri.

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