Editing Epacris impressa (section)

===Variation in flower colour and length===
{{Multiple image
| align     = right
| direction = vertical
| header    = Forms of ''E. impressa''
| width     =
| image1    = Epacris impressa white 3984.jpg
| alt1      = white-flowered shrub
| caption1  = White-flowering form, southern Victoria
| image2    = Common Heath.jpg
| alt2      = pink-flowered shrub
| caption2  = Pink-flowering form, Tasmania
| image3    = Epacris impressa red 5755.jpg
| alt3      = red-flowered shrub
| caption3  = Scarlet-flowering form, Wilsons Promontory
}}

In 1977 Helen Stace and Yvonne Fripp from [[La Trobe University]] studied 195 populations of ''Epacris impressa'' in Victoria, South Australia and Tasmania and found that 120 consisted of mixed stands of two or more [[Race (biology)|races]] while 75 populations were of one race only. They identified four races based on the following corolla characteristics:<ref name=StaceI/>

*white-flowered with a markedly shortened corolla that is {{convert|9-12|mm|in|frac=8|abbr=on}} long and red-purple anthers,<ref name=StaceI/> usually found in sites with greater sun exposure.<ref name=StaceII/> Occurring throughout the species range,<ref name=StaceI/> this form is the most widely distributed.<ref name=StaceII/> 
*pink-flowered, with a longer corolla that is {{convert|12-19|mm|in|frac=8|abbr=on}} long and cream-white anthers, in more shaded sites.<ref name=StaceII/> This form occurs throughout the species range.<ref name=StaceI/> Field work in Victoria and Tasmania found that pink-flowered plants in mixed populations often have pink or red anthers.<ref name=StaceIII>{{cite journal |last1=Stace |first1=Helen M. |last2=Fripp |first2=Yvonne J. |year=1977 |title=Raciation in ''Epacris impressa''. III.Polymorphic Populations  |journal= [[Australian Journal of Botany]]|volume=25 |pages= 325–36|doi= 10.1071/BT9770325 }}</ref>
*long scarlet race, with orange-red flowers and corolla {{convert|15-19|mm|in|frac=8|abbr=on}} long and cream-white anthers. Those from the granitic mountains of [[Wilsons Promontory]] and near [[W Tree, Victoria|W Tree]] in East Gippsland in Victoria flower between April and November. Other localities where this race has been recorded include the Howe Ranges and [[Clyde Mountain]] in New South Wales.<ref name=StaceI/>
*broad pink or white, the ''grandiflora'' race from the [[Grampians National Park|Grampians]] and [[Mount Arapiles]] in Victoria. Plants of this race are taller, often reaching {{convert|2|m|ftin}} in height. White or pink colour bear no relation to corolla length. Plants from Mount Arapiles are always pink-flowered.<ref name=StaceI/>
 
The long-pink and short-white races frequently occur in close proximity to each other; in these mixed populations the former tends to flower in winter and the latter in spring.<ref name=StaceI>{{cite journal |last1=Stace |first1=Helen M. |last2=Fripp |first2=Yvonne J. |year=1977 |title=Raciation in ''Epacris impressa''. I. Corolla Colour and Corolla Length.  |journal= [[Australian Journal of Botany]]|volume=25 |issue= 3|pages= 299–314|doi= 10.1071/BT9770299}}</ref><ref name=StaceII>{{cite journal |last1=Stace |first1=Helen M. |last2=Fripp |first2=Yvonne J. |year=1977 |title=Raciation in ''Epacris impressa''. II. Habitat Differences and Flowering Times.  |journal= Australian Journal of Botany|volume=25 |issue= 3|pages= 315–23|doi= 10.1071/BT9770315}}</ref> The question has been raised whether these different forms are becoming incompatible. However, controlled cross-pollination between plants with short and long corollas showed that there was no incompatibility between them.<ref name=Obrien89>{{cite journal | title= The Breeding Biology of ''Epacris impressa''. Is This Species Heterostylous? |author1=O'Brien, Susan P. |author2=Calder, D.M. | journal= Australian Journal of Botany |volume=37|issue=1|pages=43–54 |year= 1989 |doi=10.1071/BT9890043}}</ref>

Pink-flowering populations have a relatively distinct [[genome|genetic makeup]], whereas red or white flowering populations have more evident sharing of genetic traits.<ref name=Conomikes>{{cite report|author=Conomikes, Melanie|title=''Epacris impressa'' Labil: Inoculation of cuttings with ericoid mycorrhizal fungus and DNA fingerprinting of floral races – Final Report to the Australian Flora Foundation|date=February 2008|url=http://www.aff.org.au/Conomikes_Epacris_final.pdf|access-date=22 April 2010|url-status=dead|archive-url=https://web.archive.org/web/20090912184337/http://www.aff.org.au/Conomikes_Epacris_final.pdf|archive-date=12 September 2009}}</ref> Research based on [[DNA profiling]] has revealed substantial genetic diversity within and between flower colour races and site populations. This has implications for vegetation projects in that [[provenance]] material needs to be collected from a wide geographic area to maintain this diversity.<ref name=Conomikes2012>{{Cite journal | last1= Conomikes | first1= Melanie | last2= Moore | first2= Gregory M. | last3= McLean | first3= Cassandra | year= 2012 | title= Genetic Analysis Reveals a Wide Regional Provenance Distribution for ''Epacris impressa'' | journal= Muelleria | volume= 30 | issue= 2 | pages= 175–82 | doi= 10.5962/p.292247 | s2cid= 251006909 | url= http://www.rbg.vic.gov.au/documents/Muelleria_30%282%29%2C_Conomikes_High_Res.pdf | access-date= 1 June 2014}}</ref>