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"The first fairly complete description of this species, under the name Citrus japonica, was published in 1784 by Thunberg in his Flora japonica; it reads in translation, as follows: "petiole winged, leaves acute, shrubby stem. Japanese: Kin Kan, vulgo Fime tats banna, Kaempf., Am. ex., Fase. V. p. 801. Growing here and there, often cultivated for its little fruits. Stem shrubby, compressed-subangulate, erect, glabrous, scarcely a foot high. Branches and branchlets alternate, compressed-angular, spinose, glabrous, erect, green. Spines solitary, in the axils of the leaves, erect divergent. Leaves few, with winged petioles, ovate, somewhat acute, entire, somewhat concave, glabrous, dark green above, paler below, erect, spreading, 1 in. [2.5 cm] long, with very minute glands ('poris'). Petioles winged. 1 line [2 mm] long. Flowers axillary, often solitary, rarely paired, pediculate, nodding. Pedicels glabrous, hanging down, 1 line [2 mm] long. Parianth, 1-phyllous, green, glabrous, minute, 5-toothed. Petals 5, white, oblong, somewhat concave, spreading, somewhat claw-like. Filaments 19, subulate, compressed, erect, in 5 more or less coherent bundles, connate, forming a cylinder, shorter than the corolla, nearly equal in length, white. Anthers oblong, small, yellow. Ovary superior, subglobose, glabrous. Style solitary, cylindrical, slightly shorter than the stamens, greenish white. Stigma simple, globose, yellow, striate, many-locular within. Fruit with fleshy peel, vesicular pulp, 9-locular [sic], the size of a cherry. Differs from the other species of Citrus especially in being a very small shrub with minute fruits; thus it can scarcely be considered as a variety of orange. It resembles Citrus medica in the axillary flowers, but differs in the winged petioles; it differs from the orange in the axillary flowers, which are solitary or paired, never in panicles. Fruit ripens in December and January, is very sweet, agreeable and edible."
"This description was evidently drawn from a very small plant, perhaps an artificially dwarfed one, such as are commonly grown in Japan. The very small leaves with axillary spines, and the fruits "the size of a cherry" strongly indicate that Thunberg was describing the round kumquat and not the oval kumquat (F. margarita). His plate of this plant published in 1800 shows a flowering twig with small leaves and well-developed axillary spines.
"Hume (1903 and 1926) described this species as follows:
"'Tree similar to Nagami [F. margarita], except that it is slightly thorny, and has the leaves somewhat smaller and rounder at the apex. Leaves oval; apex obtuse; margin crenate halfway down the length; veins slightly more conspicuous than in Nagami; borne on short rigid, inconspicuously winged petioles, 1/4 to 1/2 in. [6-13 mm] in length. Fruit spherical or somewhat oblate, 1 to 1 1/4 inches [2.5-3 cm] in diameter; golden yellow, short stalked; calyx small; rind smooth, thin, spicy to the taste and aromatic when bruised; oil cells large; pulp sparse; juice acid; sections four to seven; seeds one to three, small, oval, greenish; cotyledons two, greenish. Season same as Nagami.'" (Swingle and Reece, 1967, pp 331-332)

Information compiled by TJ Siebert. (RR Krueger, 06/03/2011)

Information and nice pictures from the UC Riverside Citrus Variety Collection

Information and nice pictures from CCPP

Permission to release to the field was NOT granted by the USDA. Plants at Rubidoux were turned over to Tim Williams, Curator, USDA Germplasm Repository. (EM Nauer, 10/1988)

Since this accession is still under quarantine, it cannot be distributed except under specific circumstances as determined by the appropriate regulatory agency. More information on this accession is available in Swingle (1943), pp 223-224, and its revision as Swingle and Reece (1967), p 251 (also available on line). It is interesting that the source of this accession is very close geographically to the source of the material described. Quite possibly this accession has (or had?) a limited geographic distribution. However, Stone (1985) reported "newer collections [of W. dolichophylla]...closely consistent in both appearance and in distribution...from the northern or northeastern area of New Guinea". Jones and Ghani (1987) also report Wenzelia spp from eastern New Guinea. (RRK, 10/2007)

Budded trees being grown for the variety collection by [RK Soost]. Trees in lathhouse B may be this accession and/or CRC 3789. This accession and CRC 3789 are not the same. See note dated 01/18/1989 on CRC 3789 accession card. (EM Nauer, ca 1989)

There are currently two accessions of F hindsii maintained at Riverside, PI 539723 and PI 539724. PI 539723 has traditionally been stated to be 2N and associated with the 'Golden bean' kumquat, whereas PI 539724 has been stated to be 4N and associated with the 'Hong Kong wild' kumquat. The two genotypes are compared in Swingle (1943), pp 349-353, and its revision as Swingle and Reece (1967), pp 333-335. Although Swingle (1943) has more information on these genotypes than does Swingle and Reece (1967), the later is more easily accessible (including an online version) and has most of the pertinent information. See also the information in Hodgson (1967), pp 582-583. It does appear that the received wisdom regarding the ploidy levels is probably incorrect. A letter from the late Prof RK Soost to the donor of PI 539723, Mr William Chapman, dated 07/12/1977 states "I finally have definitive chromosome counts on the F hindsi seedlings...from seed you supplied in 1975...confirming the somatic (diploid) count of 2n = 18. A separate letter from Prof Soost to the donor of PI 539724, Dr Bruce Bartholomew, states: "At long last we got some definitive chromosome counts on the Fortunella hindsii seedlings that I obtained from you in January 1978...The chromosome number of both seedlings is clearly 2n=18." Thus, it appears that both F hindsii accessions are diploid (although this should be confirmed again after over 30 years). In this case, apparently both PI 539723 and PI 539724 would correspond to Swingle's F hindsii var Chintou. In contrast to Swingle's statements in the above sources, Prof Soost states in the letter to Mr Chapman: "I suspect that the basic chromosome number...is 2n = 18, just like all other citrus and related genera...[t]he tetraploid would be the derived type...a tetraploid was either collected by chance of the tetraploid may be established as a cultivar in China. It's hard to believe that the tetraploid would be growing as a wild plant (as described by Swingle), in preference to the diploid." (RR Krueger, 12/21/2010)

Fruit almost all on ground. Leaves have wide winged petiole. Fruit about the size and shape of a Bearss lime, with ridged neck. Very smooth, yellow rind. Very thin rind, green flesh, very sour; probably seedless (one fruit sampled). (EM Nauer, 12/22/1987)

Most of fruit already on ground this date. Four fruits cut and one seed found. Leaves are thick and leathery. Fruit description of 12/87 still OK. (EM Nauer, 10/19/1988)

[RCRC 4016] is a cleanup of [RCRC 3793]. Rind has a nice frangrance like tropical fruits. (JA Bash, ca early 1990s)

This is not a papeda, although it was misidentified as "unknown papeda hybrid" for some time. Since it was received as Oxanthera sp., it was keyed out (R.R. Krueger, Ottillia J. Bier) using the key on p. 255 of Swingle and Reece (1967) and generally matches the description of O. neo-caledonica on p. 257. (R.R. Krueger, ca. 2000)

Malcolm Smith of Australia's DPI observed some wild Oxanthera spp.. He stated in an email dated May 10, 2004 (on file at NCGRCD) that our specimen did not resemble the plants he observed in the wild, particularly in regard to leaf morphology. He did note that Swingle stated that Oxanthera is a highly variable genus. Ottillia 'Toots' Bier opined that the differences in leaf morphology might be due to climate and cultural care. However, these differences (which indeed are rather pronounced) must make the identification of this accession questionable. Note: The information in Swingle and Reece (1967) is unchanged from the original in Swingle (1943). (RRK, 08/2007)

Malcolm Smith had the opportunity to view the Riverside accession of Oxanthera when visiting Riverside for the 2019 joint meeting of the International Organization of Citrus Virologists and International Research Conference on Huanglongbing. Malcolm thought it looked more like Oxanthera when viewed in situ than from the photographs, but its identity as Oxanthera is still somewhat suspect. Possibly a hybrid? (R.R. KRueger, 2021-09-08)

CRC 3789 and 3790 compared. 3789 tree is much smaller and less vigorous growing. Leaves slightly smaller and tend to drop more readily, making small orange fruits appear more prominent. Fruits about the size of Severinia buxifolia fruits, larger on 3789 than 3790. Non-edible fruit is mostly seeds - 2 or 3 in each. (EM Nauer, 01/18/1989)

There are currently two accessions of F hindsii maintained at Riverside, PI 539723 and PI 539724. PI 539723 has traditionally been stated to be 2N and associated with the 'Golden bean' kumquat, whereas PI 539724 has been stated to be 4N and associated with the 'Hong Kong wild' kumquat. The two genotypes are compared in Swingle (1943), pp 349-353, and its revision as Swingle and Reece (1967), pp 333-335. Although Swingle (1943) has more information on these genotypes than does Swingle and Reece (1967), the later is more easily accessible (including an online version) and has most of the pertinent information. See also the information in Hodgson (1967), pp 582-583. It does appear that the received wisdom regarding the ploidy levels is probably incorrect. A letter from the late Prof RK Soost to the donor of PI 539723, Mr William Chapman, dated 07/12/1977 states "I finally have definitive chromosome counts on the F hindsi seedlings...from seed you supplied in 1975...confirming the somatic (diploid) count of 2n = 18. A separate letter from Prof Soost to the donor of PI 539724, Dr Bruce Bartholomew, states: "At long last we got some definitive chromosome counts on the Fortunella hindsii seedlings that I obtained from you in January 1978...The chromosome number of both seedlings is clearly 2n=18." Thus, it appears that both F hindsii accessions are diploid (although this should be confirmed again after over 30 years). In this case, apparently both PI 539723 and PI 539724 would correspond to Swingle's F hindsii var Chintou. In contrast to Swingle's statements in the above sources, Prof Soost states in the letter to Mr Chapman: "I suspect that the basic chromosome number...is 2n = 18, just like all other citrus and related genera...[t]he tetraploid would be the derived type...a tetraploid was either collected by chance of the tetraploid may be established as a cultivar in China. It's hard to believe that the tetraploid would be growing as a wild plant (as described by Swingle), in preference to the diploid." (RR Krueger, 12/21/2010)

Information on 'Golden Bean' kumquat from the UC Riverside Citrus Variety Collection.

"Sm fr somewhat resembling Yuzu. Fr reddish-orange, lvs similar to Yuzu, resistance of Sudachi to citrus canker is good and gummosis resistance is good. Highly resistant to citrus root borer. Growth is slow, may have dwarfing characteristics. Trees are long-lived. Seeds are polyembryonic." (Notes from W.P. Bitters's trip to Japan, 1963, when the seeds generating this accession were collected.)

Seeds grown in Rubidoux screenhouse. Counted 27 seeds - of these 10 germ singles - 15 multiples. (J Brusca?, 07/1963)

Pltd both single and multiple sdlgs S Coastal Field Station. (J Brusca?, 08/1963)

No record if these are multiple sdlg. (Handwritten addition, unknown, ca 1970's?)

"...Sudachi [is an] acid citrus...[it] bears small fruit (20 - 25 g) and is traditionally grown in Tokushima Prefecture [Japan]. The fruit are harvested only at the green stage and are served in cut halves as a garnish." (Citrograph, 72(2):29-30,32, Dec 1986)

In The Citrus Industry, Vol I, p 368, Sudachi is listed as a "Probable hybrid (C ichangensis X C reticulata?). (EM Nauer, ca 1987)

Tree 36-14 is killing itself with extremely large crop of marbles. Way past maturity now but still on tree -- mummies from past year indicate that these suckers never drop, (EM Nauer, 02/26/1988)

A more extensive description is available in Tanaka op cit.. In that work, T Tanaka describes 'Sudachi' as being superior to established varieties (such as 'Yuzu') for use in making vinegar for flavoring fish. This was apparently its only use. Abkenar and Isshiki (2003) were able to distinguish between closely related 'Sudachi' selections using RAPD markers but were unable to specualate as to their origin as hybrids. (RRK, 01/2007)

Information on 'Sudachi' from the UC Riverside Citrus Variety Collection.

Information on 'Sudachi' from the UC Riverside Citrus Clonal Protection Program.

Dr J Furr's cross, USDCS, Indio. Budwood from J Carpenter's Phytophthora studies. This Sacaton citrumelo is from the oldest tree at Tempe Field Station, Ariz. (EM Nauer (?), ca 1987)

This accession is very different from the other two [PI 539826 and PI 539827] listed as Sacaton citrumelo. This fruit is larger and rougher; about half of the fruits are seedless, the others range from 1 to 8 or 10 seeds each. (EM Nauer, 11/21/1988)

There are currently three accessions labelled as 'Sacaton' citrumelo, PI 539823, PI 539826, and PI 539827. These were all acquired by the University of California Citrus Experiment Station in 1962, apparently in an attempt to acquire a "correct" 'Sacaton' citrumelo. Contrary to the comment from Ed Nauer shown on PI 539823, the origin of 'Sacaton' is apparently USDA, Texas, or possibly Arizona. The record for inactive accession PI 150921) indicates that it was PI'ed in 1945 from seeds collected from the Experiment Station in Winterhaven, Texas, by WT Swingle. References in the US Date and Citrus Station, Indio, accession book refer to seeds collected in Texas by JR Furr, the actual location in Texas not being stated. Olson et al (1961) report 'Sacaton' present at the USDA citrus collection at Rio Farms, Monte Alto. The Rio Farms tree is stated to have been a seedling planted in 1953 originating in Texas. It is therefore probable that 'Sacaton' originated in Texas (Winter Haven Station) and was then planted at Rio Farms and later sent to the Date and Citrus Station. PI 539826 was received at the CES from Rio Farms and appears to be the best match for the description as it has larger fruit and is seedier than the other two accessions. Note: this tree no longer existed in the 1990's when the Rio Farms collection was observed by Heinz Wutscher and Robert Krueger and John Bash. However, 'Sacaton' might be from Arizona. Swingle was in charge of the citrus breeding program (actually all of CPB) during the time period in which Albert Newcomb suggests 'Sacaton' was developed and could have taken seeds from the Sacaton Station to Winter Haven when Sacaton was closed, PI'ing them only after they arrived in Texas. Better documentation of the origin of 'Sacaton' may be available but is not currently on file at NCGRCD. Note that the suggestion that 'Sacaton' citrumelo and 'Yuma' citrange are the same is supported by Bill Bitters and previous workers. Currently, there seems to be a distinction between the "true citrumelo" (PI 539826) and the smaller fruited 'Yuma' citrange. Some additional observations should be made, a "correct" 'Sacaton' decided upon, and the other two accessions inactivated. Alternatively, 'Sacaton' and 'Yuma' could be consolidated into one accession if original fruit and tree descriptions can be located. They are not currently known to be on file at either NCGRCD or the CVC. (RR Krueger, 08/08/2012)

This is a true citrumelo. Large fruit - 2 to 2.5 inches in diameter. From R 22 T 3, Del Rio Farms. (WP Bitters, ca 1980)

From a "single" seedling. (JA Brusca, ca 1980)

The 3 Sacaton citrumelos in the collection are different from each other. This one is similar to [PI 539827] in external fruit appearancee but the rind is considerably thicker. (EM Nauer, 11/27/1988)

There are currently three accessions labelled as 'Sacaton' citrumelo, PI 539823, PI 539826, and PI 539827. These were all acquired by the University of California Citrus Experiment Station in 1962, apparently in an attempt to acquire a "correct" 'Sacaton' citrumelo. Contrary to the comment from Ed Nauer shown on PI 539823, the origin of 'Sacaton' is apparently USDA, Texas, or possibly Arizona. The record for inactive accession PI 150921) indicates that it was PI'ed in 1945 from seeds collected from the Experiment Station in Winterhaven, Texas, by WT Swingle. References in the US Date and Citrus Station, Indio, accession book refer to seeds collected in Texas by JR Furr, the actual location in Texas not being stated. Olson et al (1961) report 'Sacaton' present at the USDA citrus collection at Rio Farms, Monte Alto. The Rio Farms tree is stated to have been a seedling planted in 1953 originating in Texas. It is therefore probable that 'Sacaton' originated in Texas (Winter Haven Station) and was then planted at Rio Farms and later sent to the Date and Citrus Station. PI 539826 was received at the CES from Rio Farms and appears to be the best match for the description as it has larger fruit and is seedier than the other two accessions. Note: this tree no longer existed in the 1990's when the Rio Farms collection was observed by Heinz Wutscher and Robert Krueger and John Bash. However, 'Sacaton' might be from Arizona. Swingle was in charge of the citrus breeding program (actually all of CPB) during the time period in which Albert Newcomb suggests 'Sacaton' was developed and could have taken seeds from the Sacaton Station to Winter Haven when Sacaton was closed, PI'ing them only after they arrived in Texas. Better documentation of the origin of 'Sacaton' may be available but is not currently on file at NCGRCD. Note that the suggestion that 'Sacaton' citrumelo and 'Yuma' citrange are the same is supported by Bill Bitters and previous workers. Currently, there seems to be a distinction between the "true citrumelo" (PI 539826) and the smaller fruited 'Yuma' citrange. Some additional observations should be made, a "correct" 'Sacaton' decided upon, and the other two accessions inactivated. Alternatively, 'Sacaton' and 'Yuma' could be consolidated into one accession if original fruit and tree descriptions can be located. They are not currently known to be on file at either NCGRCD or the CVC. (RR Krueger, 08/08/2012)

This is not a true Sacaton citrumelo. Fruit is small - 1 to 1.5 inch diameter. Tree shows a great amount of die-back; fruit is yellow, smooth, seedy. (EM Nauer (?), ca 1987)

The 3 Sacaton citrumelos in the collection are different from each other. This one is similar to [PI 539826] in external appearance but the rind is considerably thinner. Also, this one appears virtually identical to PI539816, which is carried as Yuma citrange. (EM Nauer, 11/21/1988)

There are currently three accessions labelled as 'Sacaton' citrumelo, PI 539823, PI 539826, and PI 539827. These were all acquired by the University of California Citrus Experiment Station in 1962, apparently in an attempt to acquire a "correct" 'Sacaton' citrumelo. Contrary to the comment from Ed Nauer shown on PI 539823, the origin of 'Sacaton' is apparently USDA, Texas, or possibly Arizona. The record for inactive accession PI 150921) indicates that it was PI'ed in 1945 from seeds collected from the Experiment Station in Winterhaven, Texas, by WT Swingle. References in the US Date and Citrus Station, Indio, accession book refer to seeds collected in Texas by JR Furr, the actual location in Texas not being stated. Olson et al (1961) report 'Sacaton' present at the USDA citrus collection at Rio Farms, Monte Alto. The Rio Farms tree is stated to have been a seedling planted in 1953 originating in Texas. It is therefore probable that 'Sacaton' originated in Texas (Winter Haven Station) and was then planted at Rio Farms and later sent to the Date and Citrus Station. PI 539826 was received at the CES from Rio Farms and appears to be the best match for the description as it has larger fruit and is seedier than the other two accessions. Note: this tree no longer existed in the 1990's when the Rio Farms collection was observed by Heinz Wutscher and Robert Krueger and John Bash. However, 'Sacaton' might be from Arizona. Swingle was in charge of the citrus breeding program (actually all of CPB) during the time period in which Albert Newcomb suggests 'Sacaton' was developed and could have taken seeds from the Sacaton Station to Winter Haven when Sacaton was closed, PI'ing them only after they arrived in Texas. Better documentation of the origin of 'Sacaton' may be available but is not currently on file at NCGRCD. Note that the suggestion that 'Sacaton' citrumelo and 'Yuma' citrange are the same is supported by Bill Bitters and previous workers. Currently, there seems to be a distinction between the "true citrumelo" (PI 539826) and the smaller fruited 'Yuma' citrange. Some additional observations should be made, a "correct" 'Sacaton' decided upon, and the other two accessions inactivated. Alternatively, 'Sacaton' and 'Yuma' could be consolidated into one accession if original fruit and tree descriptions can be located. They are not currently known to be on file at either NCGRCD or the CVC. (RR Krueger, 08/08/2012)

"C. sunki is considered to be native to China and is said to be a widely employed rootstock in China and Taiwan." (Hodgson, 1967, pp 525-526)

"Differs from the sweet mandarin orange in having smaller fruits with intensely acid pulp. The type of this variety is the sour mandarin called sand#252;n kat in Cantonese, propagated from seed in the Swatow region of Kwantung, where it is commonly used as a rootstock for grafting. G.W. Groff in 1918, in a manuscript report covering his work on citrus done in China under Swingle's supervision for the former Bureau of Plant Industry of the U.S. Department of Agriculture, described the sand#252;n kat as follows:

"'Fruits slightly depressed-globose, 2.9-3.3 cm long, 3.3-3.6 cm diam., with smooth, loose peel about 4 mm thick, capucine yellow (Ridgway, pl. 3) when ripe; oil glands small, round, far apart, fragrant; segments 9, easily separated; segment walls thin, tender, white; core 6-8 mm diam., soft; pulp deep chrom yellow (Ridgway, pl. 3), composed of small, short, pulp-vesicles, clinging together but irregularly arranged and easily broken; juice reddish yellow, very sour; seeds about 9, rounded at one end, pointed at the other, showing white parallel lines from base to tip; leaves lanceolate-elliptical, blades 6.8 X 2.5 cm, rather acutely cuneate at the base and narrowed to a blunt apex, with about 10 pairs of lateral veins; petioles nearly wingless.'

"This variety is widely grown about Swatow, China, where it is used as a rootstock upon which to graft the Ponkan or mi-tong-kan ("honey pot orange") and other famous varieties widely exported from Swatow.

"Probably some of the other sour mandarins called kat by the Cantonese are forms of this variety. Some of the so-called kat varieties with large fruits, which as they ripen may become sweet enough to eat, are probably hybrids between the variety austera and the sweet mandarin, C. reticulata, or the sweet orange, C. sinensis." (Swingle, 1943, p 415; Swingle and Reece, 1967, pp 381-382)

A small sour mandarin. (EM Nauer, 03/1987)

Sunki is widely used as a rootstock in China but has not had extensive evaluation in other areas. It is tolerant of tristeza and xyloporosis but susceptible to exocortis. Sunki is reported to be susceptible to Phytophthora but has survived well in some trials. It is also said to be tolerant of blight-like diseases in Brazil. Trees propagated on Sunki are reported to be highly salt tolerant, moderately cold hardy, and only slightly susceptible to chlorosis on calcareous soils. Trees on Sunki have been reported to be smaller than standard in China and Texas but large in Florida and California. Fruit yield and quality are at least equivalent to trees on sour orange or Cleopatra mandarin. Sunki is polyembryonic but has a higher proportion of zygotic seedlings than many other rootstocks. (Summarized from Wutscher, 1979, p 251; Castle, 1987, pp 373-374; Castle et al, 1993, p 25)

This is the "standard" accession of 'Sunki'. A recently received selection is RRUT 444. (RR Krueger, 07/09/2009)

Too tender for the field here, keep in GH only. (EM Nauer, ca 1987)

Swingle and Reece (1967) describe this taxon thusly:
"A glabrous shrub or small tree with terete twigs bearing paired spines in the axils of the leaves; leaves 3-foliolate, the terminal leaflet ovate with a cuneate base and a rounded emarginate tip, 2-4 X 1.5-2 cm; lateral leaflets much smaller than the terminal one (1-2-2 X 0.8-1.2 cm), broadly rounded at the tip, cuneate at the base; petiolules very short (1.5-2 cm); petioles short (3-5 mm), wingless; flowers appearing singly or 2 or 3 in the axils of the leaves; peduncles short (3-4 X 1 mm); flower buds cylindrical, 10-12 X 3-4 mm; flowers 3-merous (but with 6 stamens); sepals small (1.5-2 mm long), 3-lobed, green, persistent; petals white, 10-13 X 3.6-4.5 mm; staminal filaments slender, glabrous, 9-11 mm long, anthers oblong, 2 X 1 mm; disk annular or short-cylindric; ovary ovoid or fusiform with 3 locules, each with 1 ovule, narrowed into a slender, deciduous style with a capitate, 3-lobed stigma; fruit ovoid or subglobose, sometimes apiculate, 1.2-1.5 cm long, dull reddish-orange or crimson when fleshy ripe; peel with many small oil glands; seeds 1-3, immersed in mucilaginous pulpy flesh.
"Triphasia trifolia is very widely grown in all tropical and subtropical regions as an ornamental shrub. It is also used for hedges. The fragrant white flowers are soon succeeded on the branches by the small dull-red berries (see fig. 3-14). The foliage is handsome, a shiny dark green, and the plant usually makes a round-topped shrub that does not grow too large for dooryard plantings. Triphasia trifolia has become naturalized in certain sections of the United States, in "hammocks, fields and cultivated grounds, coastal plain, Florida to Texas," according to Small (1933, p. 760)".

A more recent introduction of this species is RSD 2010002. It is unknown at this time how these accessions might differ. (RR Krueger, 08/09/2010)

Additional information on this accession is available from the UC Riverside Citrus Variety Collection.

Fruit medium-small, smooth rind, green with purplish/brown/red blush on some fruits, mostly pear shaped. Hard as a golf ball. (EM Nauer, 1/24/1990)

Aegle marmelos is described in Swingle and Reece (1967), pp 407 - 409. This information and very nice pictures are available from the UC Riverside Citrus Variety Collection. The other currently active accession of this genotype is PI 87496. Observations concerning rootstock compatibility as observed on the trees in CRC 12D are presented in Siebert et al (2015).

Glycosmis pentaphll is described in [Swingle and Reece, 1967], pp 208-209.

The text of Swingle and Reece (1967) as well as very nice fotos are available from the UC Riverside Citrus Variety Collection. The statement of Swingle and Reece (1967) that "The species of Glycosmis are still very inadequately described and need study more urgently than those of any other genus of the orange subfamily" is updated by Brizicky (1961), Mitra and Subramanyam (1969), and Stone (1978, 1985, 1994). (RR Krueger, 07/20/2015)

This is listed as a member of the Papeda group because it was so listed in the old [UC Citrus Experiment Station] accession book. However, The Citrus Industry, Vol I, pp 364, puts it under aurantifolia in a table of comparison of major classification systems. What is it? (EM Nauer, 1986)

The Citrus Industry doesn't give a description of C. excelsa so here 'tis: A medium size fruit - medium yellow, basically smooth but variably bumpy. Round with flattened base and blunt nose surrounded by a depressed ring. Rind thin; seedy, flesh ricey, white to yellow, very sour. Used as an indicator plant for tatterleaf-citrange stunt. (EM Nauer, 1988-01-14)

The redundant accession number PI 539192 was assigned to this genotype in error in 1990. The observations were made when it was labelled as PI 539192. This accession was received by PIO as C. aurantiifolia "mandarin lime" and was so identified in the CPB records. However, all known CES records indentify it as C. excelsa and link it to the description in Wester, 1915. The reason or source for this is not known. There are two other apparently redundant accessions of C. excelsa: PI 539194 and PI 539670. This genotype needs rationalization. (RR Krueger, 2018-09-09)

Additional information and1434130 nice photographs from the UC Riverside Citrus Variety Collection.

This accession was received from the US Horticultural Research Laboratory from a tree propagated from a tree formerly at the Whitmore Foundation Farm (WFF). The USHRL accession at WFF is stated in the WFF Accession Book to be "cpb-1-174 = fortunella sp plant china 1922". Another section in the Accession Book refers to "cpb 10174". The admitedly incomplete list of CPB numbers on file at NCGRCD does not show a CPB 1-174; however, it does show a CPB 10174 which is indeed stated to be "C japonica 'seedless kumquat'". The archival records also equate CPB 10174 with RCRC 2377. RCRC 2377 is an inactive accession at Riverside as of 1986. However, archival records for RCRC 2377 state: "This is not a kumquat...resembles a small mandarin." (comment by WP Bitters, ca 1969). This suggests that at some point, this accession of 'Sunki' was mislabelled as a seedless kumquat. A personal communication from Dr KD Bowman of USHRL received 07/08/2009 states: "Sunki is a small fruited mandarin that I have used in many crosses. I don't think it would be mistaken for kumquat by anyone very familiar with citrus. The oldest Sunki tree at Whitmore, 9E-2-22, is what I have used for most of my crosses. Regarding the greenhouse source of Sunki sent to you, I haven't seen it and can't offer much comment on that. The plant you indicated as the field source of the greenhouse tree, 9W-2-16, no longer exists at that location. That 9W-2-16 tree was moved to another location and appears to be typical of our 9E-2-22 Sunki at that new location. I would put more weight on the characteristics of our Sunki in the field than I would on any historical records about CPB numbers." Thus it appears that this is a legitimate accession of 'Sunki' irregardless of any documentation errors.

More information on 'Sunki' and a summary of its rootstock characteristics is available at PI 539678/RCRC 3143. (RR Krueger, 07/08/2009)

"The Choju kinkan or Changshou or Fukushu kumquat of Japan is a dwarf variety that is reported to be widely grown as a potted plant in CHina and also in Japan to some extent. According to Swingle [citation below], it is characterized by the broadly obovate form of the fruit, a markedly depressed apex, medium size, thin rind (for a kumquat), and a rather large number of segments (five or six, sometimes as many as eight). Seeds are few and polyembryonic. The plant is small and thornless". (Hodgson, 1967, p 583)

Obtained from Willits and Newcomb as a possible clean source of this cv which is already in the CVC (PI 539730/RCRC 3475). More information on PI 539730 is available from the Citrus Variety Collection. Tested clean but later also processed by CCPP. (RR Krueger, 06/27/2011)