Publications

Bruce Bayer has published many articles and several books on Haworthia. All are now out of print, hence this digital archive, Haworthia Updates.

Haworthia Handbook
Haworthia Handbook
National Botanic Gardens of South Africa, Kirstenbosch, Cape, 1976.

The New Haworthia Handbook
The New Haworthia Handbook
National Botanic Gardens of South Africa, Karoo Botanic Garden, Worcester, 1982.

Haworthia Revisited
Haworthia Revisited. A revision of the Genus.
Umdaus Press, Hatfield, South Africa, 1999. Well established, color-illustrated revision of the species. Hard cover. 250 pages 21 x 26 cm.


Thoughts on Haworthia. Philosophical dissertations.
Spiderwalk Services CC, Durbanville, Capetown, South Africa, 1999. Soft cover. 99 pages 21 x 29.5cm. 22 papers. Variety of subjects, ICBN, USA talks, correspondence with taxonomists and others, the enigma of Haworthia etc.

.
Since Haworthia Revisited was published Bruce has made many more habitat excursions and is still making them. He has noted geographical features, geology and the wide variability of habitat plants. Many new populations have been discovered and most have been extensively photographed. As time has passed he has written up his discoveries in Updates 1-7, revised his species list as necessary and profusely illustrated populations and their variability. These photos of plants in habitat are a “herbarium” par excellence. The following detail the publications, contents and page numbers.

Haworthia Update Essays on Haworthia – Volume 1
Umdaus Press, Hatfield, South Africa, 2002

Foreward, Preface, Acknowledgements, Introduction 
Essay 1. Haworthia gracilis, H. cymbiformis and H. cooperi in the
greater Baviaanskloof area		1-4
Essay 2. Haworthia mucronata and its new variety5-24
Essay 3. The case of Haworthia incurvula25-33
Essay 4. Haworthia cooperi and H. bolusii var. blackbeardiana34-47
Eassy 5. The Haworthias of Kaboega48-56
Essay 6. Summation – and a new solution?57-60
Epilogue61
References62


Haworthia Update Vol. 2.
Alsterworthia International, Alsterworthia International, St Michaels on Wyre (GB). 2006. Card cover. 165 A4 pages.

Catalyst and consequences1
Editor’s note2
Acknowledgement2
Introduction 3-4
Chapter 1. The curious variability of Haworthia floribunda 4-17
Chapter 2. A population of Haworthia magnifica/maraisii 18-23
Chapter 3. Where to H. limifolia 24-44
Chapter 4. Haworthia limifolia var. arcana Smith & Crouch 45-47
Chapter 5. The White Widow Reunion – Haworthia mutica 48-49
Chapter 6. How to understand H. mutica var. nigra 50-79
Chapter 7. Continuity of Haworthia on the Zuurberg 80-86
Chapter 8. Ecotypes in Haworthia 87-97
Chapter 9. New Names and Combinations in Haworthia 98-104
Chapter 10. Small Hairy Things105-109
Chapter 11. Some of the interplay of H. arachnoidea and H. mucronata110-114
Chapter 12. Haworthia rossouwii VPoelln. and the demise of H. serrata Bayer115-129
Chapter 13. A trip to Bredasdorp130-135
Chapter 14. Explaining the name Haworthia intermedia VPoelln. and others136-140
Chapter 15. Electron Scanning Photographs of Haworthia leaf surfaces141-148
Chapter 16. Nectar Sugars in Alooid minor genera and need for another model149-152
Chapter 17. Species and varieties listed153-154
Chapter 18. Bayer Accessions155-162
Index of Scientific Names and Maps163-165


Haworthia Update Vol. 3.
Alsterworthia International, Alsterworthia International, St Michaels on Wyre (GB). 2007. Card cover. 167 A4 pages.

Chapter 1. Haworthia mirabilis, and the interface with Haworthia maraisii1-87
Chapter 2. Flowers of some Haworthias 88-91
Chapter 3. Alooideae – Asphodelaceae and the genera thereof92-96
Chapter 4. Classification with purpose 97-104
Chapter 5. Something about new Haworthias 105-110
Chapter 6. Review of the annotated checklist for Haworthia – Strelitzia 14 111-113
Chapter 7. Some thoughts on recent literature of the Alooideae (Asphodelaceae) 114-118
Chapter 8. Review of World of Haworthias, Vol. 2119-122
Chapter 9. A response to Paul Forster’s review of “Haworthia Revisited”123-127
Chapter 10. “Rocks of Ages” – Another review128-131
Chapter 11. Haworthia as a problem genus – 34 years on132-134
Chapter 12. Plant classification – a sociology of ignorance?135-139
Chapter 13. Haworthia IS confusing140-156
Chapter 14. A population of Haworthia heidelbergensis157-161
Chapter 15. The Super Species Proposal165-167


Haworthia Update Vol. 4.
Alsterworthia International, Alsterworthia International, St Michaels on Wyre (GB). 2008. Card cover. 108 A4 pages.

Introduction 1 
That squadron of Haworthias from Albertinia eastwards2-28
A glimpse of the super-species H. nortieri29-60
More new things and ideas in Haworthia61
Some variation in Haworthia mirabilis var. sublineata62-77
What did I learn yesterday?78-79
Credulity stretched80-82
The brutality of the reality of Haworthia83-86
Closer to closure87
Closure87
Post closure Bruce Bayer88-91
Appendices (Some relevant older articles which may have escaped the eye.) 
Haworthias – small relatives of aloes92-97
Variation in Haworthia with particular reference to Haworthia glauca98-101
Haworthia and Nomenclatural Confusion102-105
Index of scientific names106-107
About Alsterworthia International108
Haworthia Study – journal of the Japanese Haworthia Society108


Haworthia Update Vol. 5.
Alsterworthia International, St Michaels on Wyre (GB). 2009. Card cover. 199 A4 pages.

Part 1 
Chapter 1. Winding down on Haworthia1-2
Chapter 2. Haworthia Reality Check3-4
Chapter 3. Haworthia deglamorized. A recapitulation5-18
Chapter 4. Haworthia retusa19-38
Chapter 5. Haworthia mirabilis39-70
Chapter 6. Haworthia floribunda71-83
Chapter.7. Haworthia minima84-90
Plant and other colour photographs index90-91
Part 2 
Chapter 8. An extension of H. rossouwii92-95
Chapter 9. More on H. floribunda and H. mirabilis96-101
Chapter 10. Haworthia ‘enigma’ and H.. mutica var. nigra102-128
Chapter 11. What is Haworthia schoemanii?129-132
Chapter 12. More on H. venosa ‘granulata’133-138
Chapter 13. A February 2009 miscellany139-166
Chapter 14. Haworthia jakubii – another new species?167-169
Chapter 15. A view of Haworthia marumiana ‘dimorpha’170-181
Chapter 16. New populations of Haworthia chloracantha,
H. parksiana and H. kingiana		182-191
Haworthia species list – Bruce Bayer Feb 22nd 2009192-193
Acknowledgements194
Plant and other colour photographs index195-196
Haworthia Study196
Haworthia Books by Bruce Bayer, Ingo Breuer & Dr. M. Hayashi197
Alsterworthia International198-199


Haworthia Update Vol. 6.
Alsterworthia International, St Michaels on Wyre (GB). 2010. Card cover. 104 A4 pages.

Introduction1
Haworthias and Chameleons2-9
Towerlands. Haworthia retusa ‘turgida’10-13
Still more about Haworthia on Kaboega14-22
Haworthia emelyae and some of its variants23-40
Haworthia emelyae ‘major’ and multifolia. New populations41-53
Die Nekkies and Biomes and Haworthia maculata54-67
Taking Haworthia cooperi further – Kliprivier68-73
A fleeting look at H. arachnoidea74-86
Interesting nursery plants87-89
Non-pilose “pilosa”90-95
North and Northwest of the Potberg96-100
A look at Aloe haworthioides101-102
Plant index103-104

Haworthia Update Vol. 7.
Alsterworthia International, St Michaels on Wyre (GB). 2012. A4 size, printed on A3 paper, folded and stapled. 250 pages in 4 parts. Part 1 has over 330 photos, Part 2 over 280, Part 3 over 330 and Part 4. over 160.

Part 1 
Chapter 1 – Haworthia retusa ‘nigra’ – Another grand final2-61
Part 2 
Chapter 2 – Further exploration in Haworthia. Further to finale2-29
Chapter 3 – A field trip to the Potberg area30-83
Part 3 
Chapter 4 – What is typical Haworthia mutica?1-4
Chapter 5 – Still more Haworthia mutica and Haworthia mirabilis 5-23
Chapter 6 – Field trip to Van Reenes Crest and Niekerkshek 24-57
Part 4 
Chapter 7 – More on Haworthia mirabilis and H. mutica from
east of Bredasdorp		 1-29
A rationalization of names in Haworthia, A list of species with
new combinations and new synonyms by M.B. Bayer and J.C. Manning.		30-40

Haworthia Update Vol. 8.
Alsterworthia International, St Michaels on Wyre (GB). 2012. A4 size, printed on A3 paper, folded and stapled. 68 pages.

Plant Names – a word of warningiii
Haworthia flowers – some comments as a character source1
Overview1
1. The Plants2-18
2. The Raceme19-21
3. The Bracts21
4. The Buds22-23
5. The Flowers24-43
6. The Capsules44-46
7. The Seeds46-47
Discussion and Conclusion48-49
Appendix 1 – Haworthia flowers – some comments as a character source50-55
Appendix 256-58
Appendix 359-61

Haworthia Update Vol. 9.
Alsterworthia International, St Michaels on Wyre (GB). 2013. A4 size, printed on A3 paper, folded and stapled. 58 pages.

A myth corrected to Haworthia maculata var. livida (Bayer)
Bayer and flowers ignored		1-51
Conclusion & Acknowledgement52
My view of names53-54

Haworthia Update Vol. 10.
Alsterworthia International, St Michaels on Wyre (GB). A4 size, printed on A3 paper, folded and stapled. 52 pages.

Appendix 4 – Haworthia flowers – some comments as a character source3-11
Appendix 5 – Haworthia flowers – some comments as a character source12-13
Appendix 6 – Haworthia flowers – some comments as a character source14-21
Appendix 7 – Haworthia flowers – some comments as a character source22-25
Appendix 8 – Haworthia flowers – some comments as a character source26-30
Appendix 9 – A report on H. mirabilis and H. rossouwii ‘minor’ Roovilei,
NNE Bredasdorp		31-39
Appendix 10 – An additional report on H. mirabilis and H. rossouwii ‘minor’,
Rooivlei and Bredasdorp, N and NNE Bredasdorp		40-49

Haworthia Update Vol. 11
Alsterworthia International, St Michaels on Wyre (GB). 2014. A4 size, printed on A3 paper, folded and stapled. 56 pages.

Still another view.3-8
A sequel … still another view of H. retusa and H. mirabilis9-19
Die Nekkies – a further visit and updated information20-36
Die Nekkies – a selection of Haworthia maculata with their leaf faces
and backs showing variability over this extensive area		37-45
A further report on Haworthia mirabilis in the Greyton area. Appendix 11
to Haworthia Updates Vol. 8.		46-54

Bibliography

Bayer, M.B.

(1962) A new variety of Haworthia limifolia from Natal. J. S. African Bot. 28:215.

(1970) Haworthia as a problem genus. Cact. Succ. J. (US) 42:251-254. [link]

(1971a) Changes in the genus Haworthia Duval. Ibid 43:157-162.

(1971b) Haworthias in the Robertson Karoo – South Africa. Journal of the Cactus and Succulent Society of New South Wales 8:9.

(1972) Anguish among the Haworthias. Cact. Succ. J. Gr. Brit. 34(2):35-37.

(1972) Natural variation and species delimitation in Haworthia Duval: Part 1. Haworthia reticulata Haw. Natl. Cact. Succ. J. 27(1):10-13.

(1972) do. Part 2. Haworthia herbacea (Miller) Stearn. ibid. 27(2):51-54.

(1972) A new species of Haworthia (Liliaceae). J. S. African Bot. 38:125.

(1972) Reinstatement of the genera Astroloba and Poellnitzia Uitew. (Liliaceae- Aloineae). Natl.Cact.Succ.J. 27(3):77-79. [link]

(1973) Leaf spirals in Haworthia. Aloe 11(3):31.

(1973) Two new species of Haworthia (Liliaceae). J. S. African Bot. 39:249.

(1973) Natural variation and species delimitation in Haworthia Duval: Part 3. Haworthia reinwardtii Haw. and Haworthia coarctata Haw. Natl. Cact. Succ. J. 28(3):80-86.

(1974) Haworthia Duval: Section Retusae fide Scott – additional comment. Aloe 12:89-98.

(1974) Haworthia ‑ small relatives of Aloe. Excelsa 4:17.

(1974) New Haworthias. Cact. Succ. J. (US) 42:75-78.

(1975) The retuse Haworthias. Excelsa 5:83-90.

(1976) Haworthia Handbook. A guide to the species, with identification keys and illustrations. Kirstenbosch (ZA): National Botanic Gardens of South Africa.

(1977) Corrections to Haworthia Handbook. Natl. Cact. Succ. J. 32:18.

(1977) Haworthia mirabilis Haw. Excelsa 7:37.

(1978) Reflections on G.G. Smith’s Haworthia collection. ibid. 8:46-52.

(1979) Natural variation and species delimitation in Haworthia Duval: Part 4. Haworthia emelyae von Poelln. and a new variety. Natl. Cact. Succ. J. 34(2):28-31.

(1980) Looking for Haworthias. Calandrinia :57. Succulent publications of South Australia.

(1980) A story of Haworthia nitidula v. Poelln. (= H. mirabilis Haw.). Cact. Succ. J. (US) 52:10.

(1981) Three new species of Haworthia. J. S. African Bot. 47:789.

(1982) Natural variation and species delimitation in Haworthia Duval: Part 5. Haworthia angustifolia Haw. Natl. Cact. Succ. J. 37(2):31-33.

(1982) Observations on the G.G.Smith collection of Haworthia. Natl. Cact. Succ. J. 37(4):105-106.

(1982) The New Haworthia Handbook. A revised guide to the literature of the genus, with discussion of the species, identification keys and colour illustrations. Kirstenbosch (ZA): National Botanic Gardens of South Africa.

(1984) The Cape Flora and the Karoo – A winter rainfall biome versus a fynbos biome! Veld & Flora, March 1984

(1986) Haworthia and nomenclatural confusion. British Cactus & Succulent Journal 4(2):45-47.

(1986) Haworthia – confusion reigns again. Excelsa 12:91.

(1987) Natural variation and species delimitation in Haworthia Duval: Part 6. Haworthia maculata (v. Poelln.) Bayer. British Cact. Succ. J. 5(1):13-15.

(1988) Haworthias and the Cape Climate. Haworthiad 4(3):6-8.

(1996) Harry May’s enigma, and A miscellany. Haworthiad 10(2):130-135.

(1996) A preview of a Newer Haworthia Handbook. Aloe 33:55-56.

(1996) What is a Haworthia species? Aloe 33:65-66.

(1997) What is the shape of an elephant? Aloe 34:6.

(1997) Haworthia floribunda comments. Haworthiad 11(1):6-7.

(1997) Of Haworthia starkiana and other cabbages and clay-footed kings. Haworthiad 11(3):84-89.

(1997) Factual information about BB. Haworthiad 11(4):104-106, 116.

(1997) Gravitational collapse and black holes in Haworthia. Ibid 119-125.

(1998) An open letter to an American. Haworthiad 12(1):16-22.

(1998) Haworthiad 11.3 – Bayer’s pennyworth. Ibid 26-33.

(1998) Haworthia cymbiformis var. reddii (Scott) Bayer – a test of an hypothesis – part 1. Haworthiad 12(2):48-52.

(1998) An open letter to a scientist. Ibid 61-64.

(1998) Haworthia cymbiformis var. reddii (Scott) Bayer – a test of an hypothesis – part2. Haworthiad 12(3):90-94.

(1998) Reviews and reactions. Ibid 113-115.

(1998) Haworthia sordida et al. Haworthiad 12(4):119-120.

(1999) Is classification science or art. Asklepios 77:3-10. [link]

(1999) Comments on Haworthiad 12:3 & 4. Haworthiad 13(2):68-70.

(1999) A climb up the Audensberg. Haworthiad 13(3):99-101.

(1999) A shadow of the past – Haworthia arachnoidea again. Haworthiad 13(4): 132-135.

(1999) Haworthia Revisited. A revision of the genus. Hatfield (ZA): Umdaus Press.

(2000) Thoughts on Haworthia (ISBN No. 0-620-25323-1) Spiderwalk Services, Cape Town.

(2001) Haworthia rossouwii Poelln. and the demise of H. serrata Bayer. Aloe 38(1-2): 31–36, ills. [link]

(2002a) Haworthia update. Essays on Haworthia — Volume 1. Hatfield (ZA): Umdaus Press.

(2002b) An odd population of Haworthia arachnoidea var. nigricans. Aloe 38(3-4): 76–79, ills.

(2002c) Small Hairy Things. Haworthiad 16(2):48-52. [link]

(2002d) New names and combinations in Haworthia. Ibid 62-71. [link]

(2002e) A Trip to Bredasdorp. Haworthiad 16(3):86-95.

(2003) Haworthia rossouwii. Haworthiad 17(1):8-9.

(2003) H. mutica var. nigra indeed! Ibid 24-32.

(2003a) Where to Haworthia limifolia? Aloe 40(2): 41–51, ills., map. [link]

(2003) Corrections. Haworthiad 17(2):45-47.

(2003) Consequent to H. mutica var. nigra indeed! Ibid 53-54.

(2003) Still consequent to H. mutica var. nigra indeed! Ibid 60-62.

(2003) Observations with application to “namenklutter”. Haworthiad 17(3):83-85.

(2003b) Some of the interplay of Haworthia arachnoidea and H. mucronata. Haworthiad 17(3): 94–99, ills., map. [link]

(2003c) Classification with purpose. Alsterworthia International, special issue No.3. [link]

(2003d) Ecotypes in Haworthia. Aloe 40:10-15. [link]

(2003) Have you seen this plant? Veld & Flora 89(1):34 – 35.

(2004) Astroloba asprugmurcorrata – a new explanation. Haworthiad 18(1): 4.

(2004a) Still on about Haworthia mutica var. nigra. Haworthiad 18(1): 21–33, ills., map.

(2004b) Haworthia arachnoidea and H. nortieri. Haworthiad 18(2): 44–51, ills.

(2004c) Continuing the saga of Haworthia mutica var. nigra. Haworthiad 18(2): 52–57, ills.

(2004) Another twist to the story of H. mutica var. nigra. Haworthiad 18(3):92-101.

(2004) Review of the annotated checklist for Haworthia in Strelitzia 14. Haworthiad 18(3):102-106.

(2005) Completing the saga of H. mutica var. nigra? Haworthiad 19(1):7–13, ills.

(2005) Astroloba flowers. Ibid 14-16.

(2005) Some variation in Haworthia venosa var. venosa. Haworthiad 19(2):40-42.

(2005) A note on Haworthia viscosa. Ibid 50-51.

(2006) Some thoughts on recent literature of the Alooideae (Asphodelaceae). Alsterworthia International 6(1):9-12.

(2006) More about Haworthia on Kaboega. Alsterworthia International 6(2):2-5.

(2006) Haworthia maraisii in the West. Ibid 6-7.

(2006) Why Updates 2 and 3. Ibid 12-13.

(2006) Haworthia update. Essays on Haworthia. Volume 2. St. Michaels on Wyre (GB): Alsterworthia International.

(2006) An answer to Mr. Breckenridge.  Haworthiad 20(2):49-51.

(2006) The sources of confusion in Taxonomy. Ibid 52-53. ¨

(2006) Haworthia variegata var. modesta – Potberg.  Haworthiad 20(3):75-77.

(2006) Haworthia variegata var. hemicrypta – Potberg. Ibid 78-85.

(2006) A challenge ignored? Ibid 92-93.

(2007a) Haworthia update. Essays on Haworthia. Volume 3. Part 1 / Part 2. St. Michaels on Wyre (GB): Alsterworthia International.

(2007) Haworthia Duval. A revised species list. Alsterworthia International 7(2):20-22.

(2007b) Comments on Haworthia mortonii I. Breuer. Alsterworthia International 7(3): 25–27, ills.

(2007) Draaihoek, Albertinia and H. floribunda var. denta. Haworthiad 21(1):14-17.

(2007) An attractive form of H. cooperi var. isabellae. Ibid 23.

(2007) A look at Aloe haworthioides. Haworthiad 21(2):36-38. [link]

(2007) Closer to closure. Ibid 42-43. [link]

(2007) Credulity stretched. Ibid 47-50.

(2007) The brutality of the reality of Haworthia. Ibid 56-62. [link]

(2007) The interaction of H. floribunda and H. maraisii. Haworthiad 21(3):67-69.

(2007) Cogmanskloof Haworthia maraisii. Ibid 75-78.

(2007) Haworthia maraisii at Napky. ibid 83-85.

(2008) Haworthia update. Essays on Haworthia. Volume 4. St. Michaels on Wyre (GB): Alsterworthia International.

(2008) More trenchant botany. Alsterworthia International 8(1):21-23. 

(2008) Collection numbers, and On reflection. Alsterworthia International 8(2):6-7.

(2008) Non-pilose “pilosa”. Haworthiad 22(1):12-15.

(2008) North and northwest of the Potberg. Ibid 26-28.

(2008) An informal new variety of H. cooperi. Haworthiad 22(2):36-40.

(2008) Taking Haworthia cooperi further. Ibid 49-53.

(2008) A fleeting look at H. arachnoidea. Haworthiad 22(3):68-73.

(2008) Haworthia reality check. Ibid 84.

(2008) Haworthia species and varieties list. Ibid 93-95.

(2009) Haworthia update. Essays on Haworthia, Volume 5. Part 1 / Part 2. St. Michaels on Wyre (GB): Alsterworthia International.

(2009) Some detail about Haworthia baccata Smith. Alsterworthia International 9(1):20.

(2009) Haworthia mirabilis and the interface with Haworthia maraisii. Ibid 21-28.

(2009) Species variability. Alsterworthia International 9(2):10-11.

(2009) Haworthia minima.  Haworthiad 23(1):5-7.

(2009) Some Robustiped pictures. Haworthiad 23(2):36-40.

(2009) Er … how was that again? Ibid 47-51.

(2009) Another H. glauca variant. Ibid 56-63.

(2009) Haworthia ‘enigma’ and H. mutica var. nigra. Haworthiad 23(3):73-80.

(2010a) Haworthia update. Essays on Haworthia. Volume 6. St. Michaels on Wyre (GB): Alsterworthia International.

(2010) Haworthias and Chameleons. Alsterworthia International 10(1):16-23.

(2010) Supplement – Haworthia Update Volume 5 Part 2 replacement for Chapter 14. Haworthia jakubii – another new species? Ibid 24-27.

(2010) More on H. venosa ‘granulata’. Haworthiad 24(1):6-9.

(2010b) Variants of Haworthia aristata at Kaboega. ibid 20–23, ills.

(2010) When is a review helpful and useful? Ibid 28-31, ills.

(2010c) Klip River plants in cultivation. Haworthiad 24(2): 36–37, ills.

(2010d) A case of mistaken identity. ibid40–41, ill.

(2010) The methodology of G.G. Smith. Ibid 54-56.

(2010e) Haworthia minima ‘opalina’. Haworthiad 24(3): 64–65, ills.

(2010f) Haworthia kingiana and H. minima variants. Ibid 68–74, ills.

(2010g) Comments on Haworthiad 24 No. 2, 2010. ibid 79–86, ills.

(2011) 2010 Variants in Haworthia. Alsterworthia International 11(1):1, 5-13, 16-19.

(2011) Some more last closing thoughts. Alsterworthia International 11(3):3-4.

(2011) Plants in my collection 1: Haworthia reinwardtii ‘brevicula’. Haworthiad 25(1):17.

(2011) Plants in my collection 2: Haworthia cooperi ‘puberula. Ibid 26-27.

(2011) MBB6618 Wot’s this?. Haworthiad 25(2):37, 55.

(2011) Plants in my collection 3: Haworthia cooperi ‘isabellae’. Ibid 39.

(2011) Plants in my collection 4: Haworthia cooperi ‘picturata’. Ibid 45.

(2011) Taxonomy – the tax on me. Haworthiad 25(3):59-67.

(2011) Plants in my collection 5: Haworthia mirabilis ‘velcro’. Ibid 72-73.

(2011) Plants in my collection 6: Haworthia mirabilis ‘subvelcro’ ibid 74-75.

(2011) Van Reenens Crest. Available from: https://haworthiaupdates.org/2011/10/22/van-reenens-crest/

(2012a) Haworthia update. Essays on Haworthia, Volume 7 (part 1 / 2 / 3 / 4). St. Michaels on Wyre (GB): Alsterworthia International.

(2012b) Haworthia update. Essays on Haworthia, Volume 8. St. Michaels on Wyre (GB): Alsterworthia International.

(2012c) New finds in Haworthia. Cact. Succ. J. (US) 84(1):41–50, ills., map. https://doi.org/10.2985/0007-9367-84.1.41

(2012d) Just what do we do with names for Haworthia? Cactus World 30(4):211–214. [link]

(2012) Plants in my collection 7: H. mirabilis ‘magnifica’. Haworthiad 26(1):4-5.

(2012) Plants in my collection 8: H. mirabilis ‘submagnifica’. Ibid 20-21.

(2012) Plants in my collection 9: H. mirabilis ‘subsplendens’ Haworthiad 26(2):39.

(2012) Bumbeni – the place of mud. Haworthia limifolia ibid 53-54.

(2012) Seeking limifolia. Haworthiad 26(3):72-74.

(2012) What do collectors need? Alsterworthia International 12(2):5-6.

(2012) Haworthia marxii and H. truteriorum in relation to rational classification. Alsterworthia International 12(3):6-7.

(2012) Aloe pumila, Haworthia pumila; what or who is confused? Available from: https://haworthiaupdates.org/2012/03/24/aloe-pumila-haworthia-pumila-what-or-who-is-confused/

(2012) Haworthia mirabilis magnifica, MBB6651, S Riversdale. Available from: https://haworthiaupdates.org/2012/03/25/h-mirabilis-magnifica-mbb6651-s-riversdale/

(2012) The Haworthia pollinator. Available from: https://haworthiaupdates.org/2012/03/25/the-haworthia-pollinator/

(2012) Very brief note re Haworthia nortieri flowers. Available from: https://haworthiaupdates.org/2012/05/24/very-brief-note-re-haworthia-nortieri-flowers/

(2012) Righting some miscoceptions. Available from: https://haworthiaupdates.org/2012/07/03/righting-some-misconceptions/

(2012) Comments on H. marxii. Available from: https://haworthiaupdates.org/2012/07/03/comments-on-h-marxii/

(2012) Haworthia maculata ↔ Haworthia pubescens, MBB8002 Cilmor. Available from: https://haworthiaupdates.org/2012/08/30/haworthia-maculata-h-pubescens-mbb8002-cilmor/

(2012) Addendum Haworthia pubescens MBB8011, SW Sandberg. Available from: https://haworthiaupdates.org/2012/09/05/haworthia-pubescens-addendum-mbb8011/

(2012) Genetic history – the place in Haworthia classification. Available from: https://haworthiaupdates.org/2012/09/07/genetic-history-the-place-in-classification/

(2012) Haworthia mutica (groenewaldii) and its twisted leaves. Available from: https://haworthiaupdates.org/2012/09/15/haworthia-mutica-groenewaldii-and-its-twisted-leaves/

(2012) Comprehension and significance. Available from: https://haworthiaupdates.org/2012/10/21/comprehension-and-significance/

(2012) MBB6694 Kanetvlei, Hex River Valley as a variant of Haworthia nortieri. Available from: https://haworthiaupdates.org/2012/12/29/mbb6694-kanetvlei-hex-river-valley-as-a-variant-of-haworthia-nortieri/

(2013) MBB7989 Haworthia pumila, Lemoenpoort. Available from: https://haworthiaupdates.org/2013/01/18/mbb7989-haworthia-pumila-lemoenpoort/

(2013) Plants in my collection 10: H. mirabilis ‘subpilosa’ Haworthiad 27(1):20-22.

(2013) Where I am now. Ibid 26-27.

(2013) Plants in my collection 11: Haworthia decipiens. Haworthiad 27(2):42-43, ills.

(2013) Plants in my collection 12: H. emelyae ‘breueri’?. Haworthiad 27(3):70-71.

(2013) The Haworthia pollinator. Alsterworthia International. 13(1):30, ills.

(2013) Another Haworthia pollinator. Alsterworthia International ibid 31, ills.

(2014) Leaf sequence in a Haworthia emelyae ‘comptoniana’ over a 20 month period. Alsterworthia International 14(1):26-27.

(2014) Leaf arrangement in Aloe striatula. Alsterworthia International 14(2):5.

(2014) A note on new classification. Haworthiad 28(3):74-75.

(2015) Variability and Similarity in Haworthia in Different Locations with Supporting Photographs of Plants in Habitat. Alsterworthia International 15(1):12-14.

(2015) Die Nekkies – a selection of Haworthia maculata. plants, each with a leaf back and face. ibid:15-25.

(2015) The science (of plant names). Available from: https://haworthiaupdates.org/2015/09/25/the-science-of-plant-names/

(2016) What do you think this is? Available from: https://haworthiaupdates.org/2016/06/05/what-do-you-think-this-is/

(2016) Kaboega. Available from: https://haworthiaupdates.org/2016/07/16/kaboega/

(2019) Mystery – more light on the Haworthia pygmaea/retusa/turgida species. A series. Available from: https://haworthiaupdates.org/category/mystery/ (accessed 7 March 20240).

(2021) Flowering Time. Available from: https://haworthiaupdates.org/2021/01/30/flowering-time/

(2021) Fusca. Available from: https://haworthiaupdates.org/2021/04/10/fusca/

(2021) Cooper Siding: Darkness of Ignorance! Available from: https://haworthiaupdates.org/2021/05/08/darkness-of-ignorance-cooper-siding/

(2021) Species, what species? Available from: https://haworthiaupdates.org/2021/05/15/species-what-species/

(2021) Taxonomy and Fieldwork. Available from: https://haworthiaupdates.org/2021/05/31/taxonomy-and-fieldwork/

(2021) Zuurberg cooperoid. Available from: https://haworthiaupdates.org/2021/07/26/zuurberg-cooperoid/

(2021) Maculata. Available from: https://haworthiaupdates.org/2021/08/07/maculata/

(2022) Retusa and Mirabilis Travels. A series. Available from: https://haworthiaupdates.org/category/travels/

(2022) A random note about Haworthia chlorocantha. Available from: https://haworthiaupdates.org/2022/04/23/haworthia-chlorocantha/

(2022) Tulista. Available from: https://haworthiaupdates.org/2022/04/30/tulista/

(2022) Cymbiformis Cooperi. Available from: https://haworthiaupdates.org/2022/12/06/cymbiformis-cooperi/

(2023) Gulag. Available from: https://haworthiaupdates.org/2023/02/11/gulag/

(2023) Tulista pumila. Available from: https://haworthiaupdates.org/2023/03/02/tulista-pumila/

(2023) Flowering Time Redux. Available from: https://haworthiaupdates.org/2023/03/05/flowering-time-redux/

(2023) Personal Names. Available from: https://haworthiaupdates.org/2023/03/19/personal-names/

(2023) DNA Sequencing. Available from: https://haworthiaupdates.org/2023/03/20/dna-sequencing/

(2023) Mirabilis MBB7513. Available from: https://haworthiaupdates.org/2023/06/13/mirabilis-mbb7513/

(2023) Mutica reminiscences. Available from: https://haworthiaupdates.org/2023/06/23/reminiscences/

(2023) Closing Thoughts on Haworthia, a sequel. Available from: https://haworthiaupdates.org/2023/07/14/closing-thoughts-on-haworthia/

–//–

Bayer, M.B & Pilbeam, J.W. (1974) Name changes in Haworthia concerning H. obtusa Haw. and H. pilifera Bak. Cact. Succ. J. (US) 46:166.

Bayer, M. B., Eggli, U., van Jaarsveld, E., Smith, G. F. & Supthut, D.J. (1999) From Adrian Haworth to Haworthia. Haworthia and related South African succulents. Haworthia Society, St Michaels on Wyre.

Bayer, M.B. & Dold, T. (2003) Ecotypes in Haworthia. Aloe 40(1): 10–15, ills., maps. [link]

Bayer, M.B. & Manning, J.C. (2012a) A rationalization of names in Haworthia. A list of species with new combinations and new synonyms. Alsterworthia International 12(1):7–17. [link]

Bayer, M.B. & Manning, J.C. (2012b) The Haworthia nomenclator: A list of accepted species with some guidelines for infraspecific names. Redditch (GB): Haworthia Society.

Bayer, M.B. & van Jaarsveld, E. (2019). Haworthia ASPHODELACEAE. In: Eggli, U., Nyffeler, R. (eds) Monocotyledons. Illustrated Handbook of Succulent Plants. Springer, Berlin, Heidelberg.