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58-532: Nuytsia floribunda is a hemiparasitic tree found in Western Australia . The species is known locally as moodjar and, more recently, the Christmas tree or Western Australian Christmas tree . The display of intensely bright flowers during the austral summer coincides with the Christmas season. The habit of the species may be a tree, up to 10 metres high, or as a lower shrub form. The rough bark

116-535: A classic example of convergent evolution . Roughly 1% of all angiosperm species are parasitic, with a large degree of host dependence. The taxonomic family Orobanchaceae (encompassing the genera Triphysaria , Striga , and Orobanche ) is the only family that contains both holoparasitic and hemiparasitic species, making it a model group for studying the evolutionary rise of parasitism . The remaining groups contain only hemiparasites or holoparasites. The evolutionary event which gave rise to parasitism in plants

174-405: A few or just one species. Beech drops ( Epifagus virginiana ) is a root holoparasite only on American beech ( Fagus grandifolia ). Rafflesia is a holoparasite on the vine Tetrastigma . Plants such as Pterospora become parasites of mycorrhizal fungi. There is evidence that parasites also practice self-discrimination, species of Triphysaria experience reduced haustorium development in

232-581: A higher proportion of marine flora in temperate rather than tropical waters. While no full explanation for this is available, many of the potential host plants such as kelp and other macroscopic brown algae are generally restricted to temperate areas. Roughly 75% of parasitic red algae infect hosts in the same taxonomic family as themselves, these are given the designation adelphoparasites. Other marine parasites, deemed endozoic, are parasites of marine invertebrates ( mollusks , flatworms , sponges ) and can be either holoparasitic or hemiparasitic, some retaining

290-410: A host plant. Using the resources in the seed endosperm , the dodder can germinate. Once germinated, the plant has 6 days to find and establish a connection with its host plant before its resources are exhausted. Dodder seeds germinate above ground, then the plant sends out stems in search of its host plant reaching up to 6  cm before it dies. It is believed that the plant uses two methods of finding

348-417: A host. The stem detects its host plant's scent and orients itself in that direction. Scientists used volatiles from tomato plants ( α-pinene , β-myrcene , and β-phellandrene ) to test the reaction of C. pentagona and found that the stem orients itself in the direction of the odor. Some studies suggest that by using light reflecting from nearby plants dodders can select hosts with higher sugar because of

406-402: A regionalisation of Western Australia into "natural regions", including a region that he named "Stirling", which closely matches the present-day Esperance Plains region. In the 1940s and 1950s, Charles Gardner refined Diels' regions, but split Diels' "Eyre" into western and eastern parts. In 1980, John Stanley Beard published a phytogeographical regionalisation of the state based on data from

464-485: A variety of chemical germination stimulants. Strigol was the first of the germination stimulants to be isolated. It was isolated from a non-host cotton plant and has been found in true host plants such as corn and millets. The stimulants are usually plant-specific, examples of other germination stimulants include sorgolactone from sorghum, Orobanche and electoral from red clover, and 5-deoxystrigol from Lotus japonicus . Strigolactones are apocarotenoids that are produced via

522-469: A warm, dry, Mediterranean climate , with five to six dry months. Rainfall in winter is typically between 500 and 700 millimetres (19–27 in). The main vegetation formation of the Esperance Plains region is mallee-heath; this covers about 58% of the region. Other significant vegetation forms include mallee (17%), scrub-heath (13%) and coastal dune scrub (4%). There is very little woodland;

580-495: Is a mutant Sequoia sempervirens that produces no chlorophyll; they live on sugars from neighbouring trees, usually the parent tree from which they have grown (via a somatic mutation). Parasitic plants germinate in several methods. These can either be chemical or mechanical and the means used by seeds often depends on whether or not the parasites are root parasites or stem parasites. Most parasitic plants need to germinate near their host plants because their seeds are limited in

638-437: Is attached to so many other plants that the benefit to this hemiparasitic tree is likely to be considerable. Roots and rhizomes extend out and may sucker to form new branches that give the appearance of a grove of trees. A network of fine and fragile roots arise from these larger underground parts, forming haustoria where they meet the roots of other species. These roots or rhizomes can be up to 150 metres (492 feet) in length;

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696-458: Is capable of parasitising an extraordinarily wide range of taxa with only a single published account of a species that appeared immune ( Adenanthos cygnorum ). The generalised nature of the mode of host root attachment presumably allows parasitism to occur on just about anything within reach. Nuytsia floribunda was once common and well known on the coastal plain around Perth, often remaining in remnant bushland and gardens, becoming more scarce as

754-400: Is consumed in modest quantities, and children are warned of overindulgence with the story of a monstrous, invulnerable and inescapable nocturnal being whose cry of 'Nhervalong' could be heard as it collects the gum on which it subsists. Seasonal use by other groups of the roots is also known, Ethel Hassell at Jerramungup was invited to taste some being harvested by a group of women, reporting

812-770: Is exuded from the tree may be useful. The artist Marianne North featured the tree in an illustration titled 'Study of the West Australian Flame-tree or Fire-tree’ (c. 1880), now held at Royal Botanic Gardens, Kew , and recorded her effusive impressions, "I shall never forget one plain we came to, entirely surrounded by the nuytsia or mistletoe trees, in a full blaze of bloom. It looked like a bush-fire without smoke. The trees are, many of them, as big as average oaks in our hedgerows at home, …" The early settler George Fletcher Moore described this parasitic tree as another "anomaly in this land of contradictions". A journal of systematic botany, Nuytsia , published by

870-637: Is grey-brown. Flowers are a vivid yellow-orange, appearing sometime between October and January. The inflorescence on each flowering stem may be up to one metre in length. It is a root hemiparasite, is photosynthetic and mainly obtains water and mineral nutrients from its hosts. The haustoria arising from the roots of Nuytsia attach themselves to roots of many nearby plants and draw water and therefore nutrients from them. Almost all species are susceptible to attack; haustoria have even been found attached to underground cables. In natural settings Nuytsia withdraws relatively little from each individual host, but

928-516: Is only sparsely populated; the only towns of note are Bremer Bay , Ravensthorpe , Hopetoun and Esperance . The region's topography consists of a plain that rises from near sea level to an altitude of about 200 metres (660 ft), broken in places by outcrops of granite domes and quartzite ranges. The soil is Eocene sediments overlying clay or ironstone gravel derived from the Albany-Fraser Orogen . Esperance Plains has

986-449: Is the name given to plants/algae that use rocks or boulders for attachment), while not necessarily parasitic, some species occur in high correlation with a certain host species, suggesting that they rely on the host plant in some way or another. In contrast, endophytic plants and algae grow inside their host plant, these have a wide range of host dependence from obligate holoparasites to facultative hemiparasites. Marine parasites occur as

1044-501: The Department of Agriculture and Food calls the "Intensive Land-use Zone", the area of Western Australia that has been largely cleared and developed for intensive agriculture such as cropping and livestock production. Within this area, 45.4% of the native vegetation remains uncleared. The remaining 13% of the region falls within the "Extensive Land-use Zone", where the native vegetation has not been cleared but may have been degraded by

1102-639: The Esperance Plain and to the north on the Geraldton Sandplains . ( Distribution records: The Australian Virtual Herbarium. ) The species was once common across the Swan Coastal Plain , now mostly cleared around Perth with changes in land use since colonisation. The Nyungar people made use of the species during the season Kambarang, around October to early December, obtaining bark to make shields. The gum that exudes from

1160-554: The Nuytsland Nature Reserve . It therefore has only medium priority under Australia's National Reserve System . The first biogeographical regionalisation of Western Australia, that of Ludwig Diels in 1906, included a region named "Eyre" that roughly encompassed the present-day Esperance Plains and Mallee regions. Recognition of the Esperance Plains as a distinct biogeographical region appears to have been due to Edward de Courcy Clarke . In 1926, Clarke proposed

1218-556: The Santalales order. The current treatment of Nuytsia floribunda is as a monotypic genus, Nuytsia . This species was seen as a sister taxon to Atkinsonia ligustrina (Loranthaceae) in its description as Nuytsia ligustrina by Allan Cunningham in 1817. The first description was published by Jacques Labillardière in Novae Hollandiae Plantarum Specimen (1805) as Loranthus floribundus ,

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1276-497: The Vegetation Survey of Western Australia . This new regionalisation included a district that is essentially identical with the present-day Esperance Plains region, which Beard named "Eyre Botanical District" in honour of Edward John Eyre , first explorer of the area. By 1984, Beard's phytogeographic regions were being presented more generally as "natural regions", and as such were given more widely recognisable names. Thus

1334-525: The Western Australian Herbarium , is named for this tree. The Annals of Natural History (1842) reported a specimen being grown at a government garden in 1841, and the attempt to raise the few seeds it produced; the correspondence is printed as from "H. Bidwell … of Sidney [sic]". The flowers produce large amounts of pollen and nectar that is consumed by insects. The parasitic relationship of Nuytsia floribunda with host species

1392-568: The "Eyre Botanical District" became "Esperance Plains". When the IBRA was published in the 1990s, Beard's regionalisation was used as the baseline for Western Australia. The Esperance Plains region was accepted as defined by Beard, and has since survived a number of revisions. Since Version 6.1, Esperance Plains is divided into two subregions, Fitzgerald and Recherche . Under the World Wildlife Fund 's biogeographic regionalisation of

1450-434: The Esperance Plains is known to contain 3506 indigenous vascular plant species, and a further 294 naturalised alien species. The endangered flora of the Esperance Plains region consists of 72 species, with a further 433 species having been declared Priority Flora under the Department of Environment and Conservation 's Declared Rare and Priority Flora List . Approximately 87% of the Esperance Plains region falls within what

1508-575: The Government cleared, fenced and stocked virgin crown land , then sold it to aspiring settlers; the last was a partnership with an American-based company that developed nearly 5,000 square kilometres (1,900 sq mi) of land near Esperance for sale. There has been very little clearing since 1980. More than half of the remaining vegetation is now in protected areas , such as the Fitzgerald River National Park and

1566-628: The Monotropoids. The Monotropoids include the genera Monotropa , Monotropsis , and Pterospora among others. Myco-heterotrophic behavior is commonly accompanied by the loss of chlorophyll. Esperance Plain Esperance Plains , also known as Eyre Botanical District , is a biogeographic region in southern Western Australia on the south coast between the Avon Wheatbelt and Hampton bioregions , and bordered to

1624-448: The ability to become associated with many of the other plants around them. They are termed myco-heterotrophs . Some myco-heterotrophs are Indian pipe ( Monotropa uniflora ), snow plant ( Sarcodes sanguinea ), underground orchid ( Rhizanthella gardneri ), bird's nest orchid ( Neottia nidus-avis ), and sugarstick ( Allotropa virgata ). Within the taxonomic family Ericaceae , known for extensive mycorrhizal relationships, there are

1682-564: The ability to photosynthesize after infection. These are the only parasitic plants that parasitize animal hosts. Species within Orobanchaceae are some of the most economically destructive species on Earth. Species of Striga alone are estimated to cost billions of dollars a year in crop yield loss annually, infesting over 50 million hectares of cultivated land within sub-Saharan Africa alone. Striga can infest both grasses and grains, including corn , rice and sorghum , some of

1740-409: The appearance of abundant flowers in summer, which is a spectacular display. Although Nuytsia seeds germinate readily and seedlings are easy to grow for a year or two, cultivation of the species to maturity is regarded as difficult, with little success outside its native habitat. It appears on a variety of soil types throughout Southwest Australia, the distribution of the species extends to the east of

1798-438: The carotenoid pathway of plants. Strigolactones and mycorrhizal fungi have a relationship in which Strigolactone also cues the growth of mycorrhizal fungus. Stem parasitic plants, unlike most root parasites, germinate using the resources inside their endosperms and can survive for some time. For example, the dodders ( Cuscuta spp.) drop their seeds to the ground. These may remain dormant for up to five years before they find

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1856-636: The colonists at the Swan River referred to this species as the "fire-tree", given for the resemblance of the inflorescence to a fire in its habitat. William Milligan reported that the first colonists used the term "cabbage tree", a reference to its fragile, white and spongy branches that can be snapped off as easily as the stalks of the European vegetable, cabbage . Nuytsia floribunda is well known in Southwest Australia , especially due to

1914-749: The community. Parasitic plants are major shapers of their community, affecting not just the host species but indirectly affecting others. Competition amongst host species will change due to the parasitic plant. Plant parasitism have been shown to keep invasive species under control and become keystone species in an ecosystem. In many regions, including the Nepal Eastern Himalayas , parasitic plants are used for medicinal and ritual purposes. About 400 species of flowering plants, plus one gymnosperm ( Parasitaxus usta ) and one bryophyte (the liverwort Aneura mirabilis ), are parasitic on mycorrhizal fungi. This effectively gives these plants

1972-411: The control of Orobanche and Striga species, which are even more devastating in developing areas of the world, though no method has been found to be entirely successful. Some parasitic plants are destructive while some have positive influences in their communities . Some parasitic plants damage invasive species more than native species . This results in the reduced damage of invasive species in

2030-551: The evolution is polyphyletic . Some families consist mostly of parasitic representatives such as Balanophoraceae , while other families have only a few representatives. One example is the North American Monotropa uniflora (Indian pipe or corpse plant) which is a member of the heath family, Ericaceae , better known for its member blueberries, cranberries, and rhododendrons . Parasitic plants are characterized as follows: For hemiparasites, one from each of

2088-473: The extent and density of urban development increased. Hemiparasite There is a wide range of effects that may occur to a host plant due to the presence of a parasitic plant. Often there is a pattern of stunted growth in hosts especially in hemi-parasitic cases, but may also result in higher mortality rates in host plant species following introduction of larger parasitic plant populations. Parasitic plants occur in multiple plant families, indicating that

2146-666: The grazing of introduced animals and/or changes to the fire regime. Thus about 47.3% of the total Mallee region has been cleared. The majority of clearing was undertaken by the Government of Western Australia between 1949 and 1969 under three programs: the War Service Settlement program, the subsequent Civilian Settlement program, and the Esperance Land Development program. The first two of these were programs of assisted settlement in which

2204-590: The land within 40 kilometres (25 mi) of the coast between Albany and Point Culver on the south coast of Western Australia. It has an area of about 29,000 square kilometres (11,000 sq mi), making it about 9% of the South West Province , 1% of the state, and 0.3% of Australia. It is bounded to the north by the Mallee region, and to the west by the Jarrah Forest region. The region

2262-412: The levels of chlorophyll in the leaves. Once the dodder finds its host, it wraps itself around the host plant's stem. Using adventitious roots, the dodder taps into the host plant's stem with a haustorium , an absorptive organ within the host plant vascular tissue . Dodder makes several of these connections with the host as it moves up the plant. There are several methods of seed dispersal, but all

2320-643: The loss of photosynthesis, seen in the genus Orobanche . The most specialized forms of holoparasitic plants are the four families Rafflesiaceae , Cytinaceae , Mitrastemonaceae and Apodanthaceae , lineages which independently has evolved further into endoparasites that, except for the flowers, spend their entire life cycle within the tissue of their host. To maximize resources, many parasitic plants have evolved 'self-incompatibility', to avoid parasitizing themselves. Others such as Triphysaria usually avoid parasitizing other members of their species, but some parasitic plants have no such limits. The albino redwood

2378-472: The most extensive of any known plant. The width is up to 1.2 metres in diameter, composed of multiple layers of wood and bark that allow the tree to withstand fire. An unusual characteristic of the seedlings is the four to six cotyledons rather than two. Recognised in its earliest descriptions as a species of the Loranthaceae , a family almost entirely represented by epiphytes ( mistletoes ) allied in

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2436-434: The most important food crops. Orobanche also threatens a wide range of important crops, including peas, chickpeas , tomatoes , carrots , lettuce , and varieties of the genus Brassica (e.g. cabbage and broccoli). Yield loss from Orobanche can reach 100% and has caused farmers in some regions of the world to abandon certain staple crops and begin importing others as an alternative. Much research has been devoted to

2494-591: The north by the Mallee region. It is a plain punctuated by granite and quartz outcrops and ranges, with a semi-arid Mediterranean climate and vegetation consisting mostly of mallee-heath and proteaceous scrub. About half of the region has been cleared for intensive agriculture. Recognised as a bioregion under the Interim Biogeographic Regionalisation for Australia (IBRA), it was first defined by John Stanley Beard in 1980. The Esperance Plains may be roughly approximated as

2552-408: The number of resources necessary to survive without nutrients from their host plants. Resources are limited due in part to the fact that most parasitic plants are not able to use autotrophic nutrition to establish the early stages of seeding. Root parasitic plant seeds tend to use chemical cues for germination. For germination to occur, seeds need to be quite close to the host plant. For example,

2610-485: The only woodland communities are some of Eucalyptus marginata (jarrah), Corymbia calophylla (marri) and E. wandoo (wandoo) in valleys of the Stirling Range (1%); and some E. loxophleba (York gum) and Eucalyptus occidentalis (flat-topped yate) woodland in low-lying areas. There is also a small amount of low forest on islands off the coast. 1.7% of the region is unvegetated. As of 2007,

2668-433: The parasitic plant, eventually killing it. The fourth hurdle is the host's ability to ruin the tubercle using gums and gels or injecting toxins into the tubercle . Some parasitic plants are generalists and parasitize many different species, even several different species at once. Dodder ( Cuscuta spp.) and red rattle ( Odontites vernus ) are generalist parasites. Other parasitic plants are specialists that parasitize

2726-407: The parasitic progress at the cortex of the host's roots. The second hurdle is the host's ability to secrete germination inhibitors. This prevents germination of the parasitic seed. The third hurdle is the host's ability to create a toxic environment at the location where the parasitic plant attaches. The host secretes phenolic compounds into the apoplast . This creates a toxic environment for

2784-460: The plant are moojar , moojerool , munjah and mutyal . For thousands of years, the moojar (moodja) tree's striking yellow and orange flowers have been a warning sign for Minang - Noongar people that fire and flames are coming. It flowers during the Noongar season of birak . The regional name of "Christmas tree" has been applied since the nineteenth century. James Drummond noted in 1843 that

2842-422: The presence of other Triphysaria . The mechanism for self-discrimination in parasites is not yet known. Parasitism also evolved within aquatic species of plants and algae. Parasitic marine plants are described as benthic , meaning that they are sedentary or attached to another structure. Plants and algae that grow on the host plant, using it as an attachment point are given the designation epiphytic ( epilithic

2900-414: The seeds of witchweed ( Striga asiatica ) need to be within 3 to 4 millimeters (mm) of its host to receive chemical signals in the soil to trigger germination. This range is important because Striga Asiatica will only grow about 4  mm after germination. Chemical compound cues sensed by parasitic plant seeds are from host plant root exudates that are leached nearby from the host's root system into

2958-412: The specific epithet describing the profuse flowers he had observed at Esperance. The botanist Robert Brown published a remark on the species in 1831, giving a new genus name without a formal description. A description was published by George Don using Brown's name Nuytsia , an epithet that commemorates the seventeenth-century Dutch explorer and colonial official Pieter Nuyts . The Noongar names for

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3016-436: The strategies aim to put the seed in direct contact with, or within a critical distance of, the host. A parasitic plant has many obstacles to overcome to attach to a host. Distance from the host and stored nutrients are some of the problems, and the host's defenses are an obstacle to overcome. The first hurdle is penetrating the host since the host has systems to reinforce the cell wall by protein cross-linking so that it stops

3074-469: The surrounding soil. These chemical cues are a variety of compounds that are unstable and rapidly degraded in soil and are present within a radius of a few meters of the plant exuding them. Parasitic plants germinate and follow a concentration gradient of these compounds in the soil toward the host plants if close enough. These compounds are called strigolactones . Strigolactone stimulates ethylene biosynthesis in seeds causing them to germinate. There are

3132-400: The taste of the flesh beneath an easily removed skin as sweet, brittle and somewhat watery. The wood of the tree was noted as commercially useless, and that cultivation and transplanting difficult or impractical for gardens or landscaping by the state's conservator Charles Lane Poole (1921), deeming the showy display of flowers to be its only desirable quality. Poole also notes the 'gum' that

3190-522: The three sets of terms can be applied to the same species, e.g. Holoparasites are always obligate so only two terms are needed, e.g. Plants usually considered holoparasites include broomrape , dodder , Rafflesia , and the Hydnoraceae . Plants usually considered hemiparasites include Castilleja , mistletoe , Western Australian Christmas tree , and yellow rattle . Parasitic behavior evolved in angiosperms roughly 12-13 times independently,

3248-580: The wound can be collected later, it is sweet and eaten raw. Flowers from the moodjar tree are traditionally used to make a sweet mead -like beverage during birak. Moodjar (or Muja) is regarded as a protected tree by the Nyungar peoples of Southwest Australia, the species is noted as being incorporated into rituals and having a conservation status that forbids their destruction. The plant is venerated by some who learn that it should not be sat beneath or its flowers, leaves or branches touched or taken. The sugary gum

3306-643: Was poorly understood until an investigation by the botanist D. A. Herbert was presented to the Royal Society of Western Australia , contradicting the assumption that proximity to other trees such as banksia and jarrah was a requirement. Herbert discovered the extended network of filaments that embrace the roots of many other plant species, explaining the persistence of trees conserved in agricultural land cleared for introduced crops. There are various lists of both native and introduced host species that are vulnerable to attack, however evidence suggests Nuytsia

3364-594: Was the development of haustoria . The first, most ancestral, haustoria are thought to be similar to that of the facultative hemiparasites within Triphysaria , lateral haustoria develop along the surface of the roots in these species. Later evolution led to the development of terminal or primary haustoria at the tip of the juvenile radicle , seen in obligate hemiparasitic species within Striga . Lastly, holoparasitic plants, always forms of obligate parasites, evolved over

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