CALEYI p i c

A n d r e

P o r t e n e r

NORTHERN BEACHES GROUP s January/February 2014

President CHRISTMAS LUNCH Dr Conny Harris (02 9451 3231) Vice-President Martyn Robinson (02) 9982 7964 Joint Secretaries Jan Krone (02) 9451 9609 Julia Tomkinson (02) 9949 5179 Treasurer Jennifer McLean (02) 9970 6528 Librarian Pam Gratton 0417 481 115 Talks Co-ordinator Julia Tomkinson (02) 9949 5179 Walks Co-ordinator Lynne McNairn (02) 9982 7964 Editor Jane March (02) 9938 2180 | 0407 220 380

DIARY

APS Northern Beaches meeting 7.30pm Thursday February 6, 2014 at Stony Range Regional Botanic Garden, Dee Why. Presentation:Show & Tell. Always a very popular event. Please bring your samples & stories to share p i

Supper: Georgine & Jane c

J M APS NSW Gathering on Saturday, 15 Feb On this occasion the APS NSW Gathering will be held at the Thirroul Community Centre Excelsior Hall at 352-358 Lawrence Hargrave Drive, Thirroul. Options include a visit to the beautiful Bulli Grevillea Park in the morning and talks by Peter Olde and Peter Weston on Grevilleas in the afternoon. If you want to learn more about Bulli Grevillea Park, visit their web site at http://www.grevilleapark.org/ They have a list of which includes ferns, and shrubs and trees of many native genera with information relating to many, and images of the Park and of various species.

APS NSW 2014 Region Get Together Consider planning to attend the 2014 Region Get A pleasant lunch at Stony Together which will be held in the Central Coast Area Range where conversation on Saturday/Sunday, 15/16 August, 2014. There is inevitably veered toward the still plenty of time to decide. cicadas in the branches overhead!! Many thanks to all who have submitted contributions to this edition including Conny and Martyn. ______January/February 2014 - 1 CONNY HARRIS' LOVE OF PLANTS BE INSPIRED TO GROW YOUR OWN 'MINT President Northern Beaches Group, APS VELVET' Royal Botanic Gardens & Domain Trust Mark Viler, Senior Horticulturist, Commercial Production The Australian Botanic Garden, Mount Annan

You may not be aware that the Trust has a small commercial production unit based at the Australian Botanic Garden, Mount Annan. The aim is to help promote the amazingly beautiful flora of New South Wales through the release of wild sourced native plants to the nursery industry and in turn raise awareness of the conservation activities of the Trust. We have a number of licensed growers who grow our plants and distribute labels to retail markets in Queensland, the ACT, South Australia, Victoria, Western Australia and New South As a young child I can remember going out onto the moor that was behind Wales. my house on the outskirts of Bremen in north Germany where I grew up. I was the eldest of three children but the only girl and went with my mother The first of those releases coincided with the centenary of picking grasses and the occasional flower which always found its way federation celebrations and saw the introduction of the Federation Star™ onto the kitchen table. Later on when my parents divorced, and times flannel flowers with 'Starbright' being the flagship plant. Starbright were harder, I often cycled into the nearby moor and enjoyed nature. The continues to be very popular in the retail sector and is now grown and name of flowers is common knowledge and in primary school we learned sold across Australia. about plant -fauna interaction and the way the moor grows. I found it soothing to be out in nature. The latest addition we are delighted to introduce is the rare and endangered NSW species densa 'Mint Velvet'. With As a student studying medicine I found I could combine study with my permission from National Parks and Wildlife, this is the first threatened love of botany by learning about herbal medicine. I studied with a small species from our collection to be group of women and researched herbal remedies. We knew of a group of made available to the general public. women studying theology who were investigating witches and we As a result of restrictions on extended our studies to include the plants the witches would have used commercialisation of endangered like belladonna and rosemary. By the way the nearby moor had been species they are scarcely found in called the Teufelsmoor or the Devil's Moor, so it was second nature that I the nursery trade. While the number started researching what the witches might have used. It is still a very of rare and endangered species in special environment and it radiates a particular type of atmosphere. I NSW at the time of writing stands at realized that the Teufelsmoor was a particular plant community and from 611, this is likely to increase as then on I started travelling to different environments and paying climate impacts on marginal plant particular attention to plants. communities. Not all are suitable for horticultural applications or the Coming to Australia was overwhelming. Only a few weeds were known to confines of a commercial production me and the rest was new. When I found out that my boyfriend could system; we aim to learn from our explain the difference between a eucalypt and an acacia I decided I experiences at Mount Annan to needed to find out myself and teach him. And still today there seems to be select and trial those with most an endless amount to learn. potential. The creation of PlantBank, our new research facility, is also Moving to the northern beaches in 1997 made it easy to go to the walks contributing to their preservation and and talks at the Kuringai Wildflower Garden and then join the Australian conservation through seedbanking Plant Society. Even though learning about the plants of our area remains and propagation research. Through the sale of these plants we hope to such a big subject it doesn't seem that way, learning as I am so much further inspire the appreciation of those efforts. about something that I feel so passionate about. Luckily my husband and three children not only put up with this but even showed some interest. I While releasing rare species such as 'Mint Velvet' may help their was able to do bush regeneration at their schools and pass on some of preservation, we also use plant labelling to raise awareness of threats my knowledge, especially about eucalypts. posed to plant habitat, the protection of which will ultimately decide the plant's future. These days I am trying differentiate the eucalypts in New England, a region where my brother-in-law lives and I wonder how many more years Prostanthera densa 'Mint Velvet' is also known as the villous mint bush, that will take me. But of course every walk that I lead through this area and like all mint bushes comes from the family . This aromatic reminds me that there are still plenty of plants to identify in my local patch. compact and erect shrub grows from 0.5 -2 m tall but is more commonly found growing at around one metre. The densely hirsute mid-green leaves occur in pairs, are almost triangular in shape with strongly recurved margins. The flowers are pale mauve to mauve with white and orange markings in the throat, and can occur sparingly throughout the year but are chiefly seen in spring from October to December.

The species can be found growing in sclerophyll forest and shrubland on coastal headlands and near coastal ranges on well drained sandstone soils and rocky slopes. ______January/February 2014 - 2 Prostanthera densa is seen from Nelson Bay to Beecroft Peninsula, The study found that drought appears to be the biggest threat to gum NSW. It has been recorded in the Currarong area of Jervis Bay, along trees, out of all the weather conditions it considered. with other known localities in Bass and Flinders Point in Cronulla, Garie Beach in the Royal National Park, and Gan Gan Hill, Nelson Bay which is "They can't cope with moisture stress and when you combine heat stress

where this variety, 'Mint Velvet', originates. P and drought, that is when eucalypts start to die or their canopy i c .

deteriorates," Professor McAlpine said. R u

This plant is listed as vulnerable under Schedule 1 of the Endangered s s e The fact that eucalyptus trees have long regeneration times, in Species Protection Act 1992 (Commonwealth) and is also listed as l l

B vulnerable under Schedule 3 of the Threatened Species Conservation e combination with the short dispersal distances of their seeds, indicates a r Act 1995 (NSW). d that they may not be able to keep up with the pace of climate change. m o r e The main identified threat to Prostanthera densa is urban development, The research shows that gum trees have moved from central regions of with potential threats including dieback caused by Phytophthora the country toward the east and south coast, and that migration to more cinnamomi, and grazing by Rusa Deer (Cervus timorensis). It may also moderate conditions could also have a negative effect on native wildlife. be threatened by inappropriate fire regimes, even though plants have been known to regenerate from rootstock after fire. Professor McAlpine says this is especially the case in interior regions of the continent. "Because those trees provide nectar, they provide resources for wildlife We hope you are inspired to grow your own 'Mint Velvet', pass on its story so that those animals that depend on them will not have those and feel a sense of pride that you are helping to conserve one of New resources," he said. South Wales amazingly beautiful plants in the process. He also says the local species of eucalypts are the most vulnerable to CLIMATE CHANGE THREATENS NATIVE extinction. EUCALYPTUS SPECIES WITH EXTINCTION, "They've only got small populations and they've got a very narrow range, QUEENSLAND STUDY FINDS so if a major catastrophic event like a drought or a wildfire when through, ABC RN January 13, 2014 Whitney Fitzsimmons then they would have difficulty in recovering," he said. Planet hurtling toward mass extinction event However, it is not just gum trees that are under threat from the elements. Professor Mike Coffin, a marine geophysicist from the University of Tasmania, says the planet is hurtling toward what is called a mass extinction event that could see the end of 75 per cent of the Earth's species.

Over the past 540 million years, there have been five mass extinction events that were caused by climate fluctuations and volcanic eruptions. The last such major event was 65 million years ago, when an asteroid slammed in to the Earth, wiping out 76 per cent of total estimated species.

Professor Coffin says that the evidence suggesting we are at the beginning of a sixth mass extinction event is mounting.

Photo: Research shows gum tree migration to more moderate conditions could also have a negative effect on native wildlife. (Flickr: Jar) WILD ORCHID The future is looking grim for some species of Australian eucalyptus trees, as they feel the impact of more severe heatwaves, droughts and One September morning floods. As a planet wandering The stars before light Researchers from the University of Queensland looked at such effects A flower bruised my heart. on more than 100 eucalypt species, finding that some may be wiped out from increasingly extreme weather conditions. From earth’s blood rose A naked bloom, touched The report was modelled on two temperature scenarios. The first With the sign of grief as scenario was for an increase of one degree by 2055 and an increase of Garland to this alchemy. just over two degrees by 2085. The flowers kiss and bow To their heady crown; The second, more extreme scenario, saw an increase of 1.5 and 2.5 We come from the stars and degrees in those years respectively. To stars we shall return. Professor Clive McAlpine from the University of Queensland says that Be careful where you currently, temperatures are tracking at the extreme end of the range, and Walk along a path without mitigation they will continue to do so. So long as flowers grow They touch the stars. "We're basically locked into a warming of 3.5 to four degrees globally by P i c

the end of the century unless we can have some very aggressive.

J mitigation to reduce greenhouse gas," Professor McAlpine said. M Edwin Wilson, 1967-1969, New Collected Poems, Kardooraire Press. ______January/February 2014 - 3 OLDEST GENOME MAPPED: Shown here are Amborella female flowers and fruits. PHOTOS Discovery.com Dec 19, 2013 Christina Reed

Seen here close-up under a dissecting microscope, the flowering plant Amborella trichopoda is the oldest known existing species of petal- bearing plants on Earth. Now in a series of reports published today in the journal Science, molecular geneticists have unlocked the genomic secrets of Amborella, and with it clues as to why flowers display such successful genetic diversity.

Photograph by Joel McNeal purging the DNA, it's held on to it for tens of millions of years. So you can think of this genome as a constipated glutton, that is, a glutton that has swallowed whole genomes from other plants and algae and also retained them in remarkably intact form for eons," said Palmer in a press release.

The flowering Amborella, whose mitochondrial genome is amazingly rich in foreign genes and even genomes, is endemic to the island of New Caledonia. The research on Amborella shows "compelling evidence that Photograph by Sangtae Kim mitochondrial fusion is the driving force for mitochondrial gene transfer and that incompatibility in the mechanism of mitochondrial fusion between different phyla plants versus animals or fungi provides the Many of Amborella's genes were distinct from those of non-flowering major barrier to unconstrained mitochondrial 'sex' across the plants. In its mitochondrial DNA, which tends to change less than nuclear evolutionary tree of life," said Palmer. DNA, Amborella showed a shared affiliation with mosses and green algae. Biologist Danny W. Rice of Indiana University and his team hypothesize that wounded Amborella plants obtained the shared The southwest-Australian Christmas tree, Nuytsia floribunda, which mitochondrial genomes as a result of horizontal gene transfer between parasitizes the roots of grasses to obtain water and minerals. This these other organisms it was living in close proximity with millions of parasite belongs to the group of parasitic plants (Santalales) from which years ago. the Amborella mitochondrial genome has captured many foreign genes by horizontal gene transfer. Indeed, the team discovered that Amborella's mitochondrial genome provides the largest example of horizontal gene transfer the acquisition of foreign genes from other species in any organism. Shown here are male flowers of Amborella.

Photograph by Bernd Krueger

A parasitic flowering plant (Amyema scandens) blooming in New Caledonia from its epicortical roots, which, like mistletoe, grow along the branch of its host tree. This parasite belongs to the same group of Photograph by Joel McNeal parasitic plants (Santalales) from which the Amborella mitochondrial genome has captured many foreign genes. The Indiana University team -- working with biologists from the U.S. Department of Energy, Penn State University, and the Institute of Research for Development in New Caledonia -- showed for the first time that an organelle genome has captured an entire foreign genome, in this case, four of them: three green algae and one moss. It is also the first description of a land plant acquiring genes from green algae.

"The Amborella mitochondrial genome is like the old lady in the song who swallows a fly, and then a spider, a bird, a cat, and so on, all the way to a Horse, at which point, finally, "she's dead of course," said co-author of the study Jeff Palmer, a Distinguished Professor in the Indiana University Bloomington College of Arts and Sciences' Department of Biology.

“Likewise, the Amborella genome has swallowed whole mitochondrial genomes, of varying sizes, from a broad range of land plants and green Photograph by Bernard Suprin algae.______But instead of bursting from all this extra, mostly useless DNA, or January/February 2014 - 4 OLDEST TREES ARE GROWING FASTER, STORING STRANGER THAN FICTION MORE CARBON AS THEY AGE The-scientist.com January 1, 2014 Mary Beth Aberlin sciencedaily.com January 15, 2014 Plant biology: You can't make this stuff up.

In a finding that overturns the conventional view that large old trees are Jack climbed a beanstalk so tall that it could only exist in a fairy tale. unproductive, scientists have determined that for most species, the biggest Audrey II demands that Seymour feed her larger and larger quantities of trees increase their growth rates and sequester more carbon as they age. human blood in the cult classic Little Shop of Horrors, and venomous, predatory triffids spread like kudzu in the 1951 novel The Day of the Triffids. The 2009 sci-fi movie Avatar even comes with its own guide to the exotic flora of the moon Pandora, where plants communicate with each other via “signal transduction from root to root.”

The panoply of fictional plants offers a large and varied dose of the weird p i

c and wonderful. But there's no need to resort to fiction to find truly unusual

R

. plant characteristics.

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n Our January issue explores some of these unique biological traits. “Researchers have stumbled upon some 'mind-blowing' findings in plant genomics,” reports Megan Scudellari in “Genomes Gone Wild.” Plant genomes vary enormously in size, from some 64 million to 150 billion base pairs. (The human genome rings in at about 3.5 billion.) Plants succeeded in dramatically expanding their genomes again and again through a process of chromosome-number multiplication called Mature trees. In a finding that overturns the conventional view that large old trees are unproductive, scientists have determined that for most species, the biggest trees increase their polyploidy, which usually begins with the joining of two diploid gametes growth rates and sequester more carbon as they age. (Credit: Copyright Michele Hogan) that arise because of errors in cell division. The largest known plant genome belongs to the Japanese canopy plant (Paris japonica), an octaploid with four genome duplications in its history; the largest plant, In a letter published in the journal Nature, an international research group the majestic coast redwood (Sequoia sempervirens) is a hexaploid. And reports that 97 percent of 403 tropical and temperate species grow more polyploidy has been shown to occur across species boundaries as quickly the older they get. The study was led by Nate L. Stephenson of the wellperhaps in response to stresscreating new species that combine the U.S. Geological Survey Western Ecological Research Center. Three full genomes of both parent species. Oregon State University researchers are co-authors: Mark Harmon and Rob Pabst of the College of Forestry and Duncan Thomas of the College of Transposable elements also play a part in genome size increase; and Agricultural Sciences. plants swap genes promiscuously, taking up foreign DNA from other plants and green algae but spurning genes from animals or fungi. And, of The researchers reviewed records from studies on six continents. Their course, plants acquire new genes through the traditional mutation route, conclusions are based on repeated measurements of 673,046 individual with some species boasting record rates. trees, some going back more than 80 years. This study would not have been possible, Harmon said, without long-term records of individual tree growth. Fascinating, and true, stories. "It was remarkable how we were able to examine this question on a global level, thanks to the sustained efforts of many programs and individuals.” According to Avatar's irreverent “xenobiologist” Grace Augustine, “There's some kind of electrochemical communication between the roots Extraordinary growth of some species, such as Australian mountain ash -- of the trees. Like the synapses between neurons. Each tree has 104 also known as eucalyptus -- (Eucalyptus regnans), and the coast redwood connections to the trees around it, and there are 1012 trees on Pandora.” (Sequoia sempervirens) is not limited to a few species, the researchers It's science fiction, and set almost 150 years in the future on a distant said. "Rather, rapid growth in giant trees is the global norm and can exceed moon, but the ideas about plant communication at least have roots in 600 kg (1,300 pounds) per year in the largest individuals," they wrote. "In reality. human terms, it is as if our growth just keeps accelerating after adolescence, instead of slowing down," said Stephenson. "By that In “Plant Talk” Dan Cossins brings together the latest research about how measure, humans could weigh half a ton by middle age, and well over a ton plants communicate both aboveground via airborne chemicals and at retirement.” belowground by means of soluble compounds exchanged between the roots of different plants and via threadlike fungal networks interwoven The report includes studies from the Pacific Northwest. Harmon and his symbiotically through the roots of most plants. There is even some colleagues worked in forest plots -- some created as early as the 1930s -- at evidence that plants may relay and “listen” to acoustic messages from the H.J. Andrews Experimental Forest east of Eugene and Mount Rainier other plants. If researchers can decipher “the molecular lingua franca of National Park. Researchers measured growth in Douglas-fir, western plant communication. . . . They could then begin to clarify the ecological hemlock, Sitka spruce, western red cedar and silver fir. The National significance of the phenomenon and, potentially, help farmers grow Science Foundation and the Pacific Northwest Research Station of the hardier crops,” Cossins writes. Plants communicating is surely weird and USDA Forest Service provided funding. wonderful, but the science behind the phenomena is maturing rapidly. “This idea is not strange anymore,” says one researcher.

Under the auspices of the Smithsonian Institution's Center for Tropical Also in this issue, read about bioprospecting for gold using leaves of trees Forest Science, Thomas and colleagues in Africa established a 123-acre growing atop deposits of the precious metal and a short report on the forest research site in Cameroon in 1996. They measured growth in about phenomenon of halotropism: how roots actively grow away from areas of 495 tree species. high salinity.

"CTFS does very important work facilitating collaboration between forest Outside of plant biology, Randal Halfmann discusses a less well-known ecologists worldwide and therefore enabling us to gain a better insight into side of prion proteins, which can misfold and aggregate to form the the growth of trees and forests," Thomas said. "This model for collaboration amyloid fibrils that have been implicated in neurodegenerative diseases was the basis of the Nature study.” While the finding applies to individual such as mad cow, Alzheimer's, and Parkinson's. In “The Bright Side of trees, it may not hold true for stands of trees, the authors cautioned. As they Prions” Halfmann writes of their emerging positive roles in memory age, some trees in a stand will die, resulting in fewer individuals in a given formation, in the regulation of translation, and in our innate ability to fight area over time. off diseases. That, too, seems weird but wonderful. ______January/February 2014 - 5 AMBER FOSSIL REVEALS ANCIENT "New associations between these small flowering plants and various REPRODUCTION IN FLOWERING PLANTS types of insects and other animal life resulted in the successful Sciencedaily.com January 3, 2014 distribution and evolution of these plants through most of the world today," he said. "It's interesting that the mechanisms for reproduction that are still with us today had already been established some 100 million A 100-million-year old piece of amber has been discovered which years ago.” reveals the oldest evidence of sexual reproduction in a flowering plant -- a cluster of 18 tiny flowers from the Cretaceous Period -- with one of them in the process of making some new seeds for the next generation. The fossils were discovered from amber mines in the Hukawng Valley of Myanmar, previously known as Burma. The newly-described genus and species of flower was named Micropetasos burmensis. The perfectly-preserved scene, in a plant now extinct, is part of a portrait created in the mid-Cretaceous when flowering plants were changing the face of the Earth forever, adding beauty, biodiversity and food. It appears KOALAS' LOW-PITCHED VOICE EXPLAINED BY identical to the reproduction process that "angiosperms," or flowering UNIQUE ORGAN plants still use today. Sciencedaily.com Dec. 2, 2013

The pitch of male koalas' mating calls is about 20 times lower than it should be, given the Australian marsupial's relatively small size. Now, researchers reporting in the Cell Press journal Current Biology on December 2 have discovered their secret: koalas have a specialized sound-producing organ that has never before been seen in any other land- dwelling mammal. The key feature of this newly described organ is its location outside the voice box, what scientists call the larynx.

Ancient flower. (Credit: Image courtesy of Oregon State University) Visuals Unlimited, Inc./Gerard Lacz/Getty

Researchers from Oregon State University and Germany published their "We have discovered that koalas possess an extra pair of vocal folds that findings on the fossils in the Journal of the Botanical Institute of Texas. are located outside the larynx, where the oral and nasal cavities connect," says Benjamin Charlton of the University of Sussex. "We also The flowers themselves are in remarkable condition, as are many such demonstrated that koalas use these additional vocal folds to produce plants and insects preserved for all time in amber. The flowing tree sap their extremely low-pitched mating calls.” covered the specimens and then began the long process of turning into a fossilized, semi-precious gem. The flower cluster is one of the most The koala's bellow calls are produced as a continuous series of sounds complete ever found in amber and appeared at a time when many of the on inhalation and exhalation, similar to a donkey's braying, Charlton flowering plants were still quite small. explains. On inhalation, koala bellows sound a bit like snoring. As the animals exhale, the sound is more reminiscent of belching. And, as Even more remarkable is the microscopic image of pollen tubes growing Charlton says, "they are actually quite loud.” out of two grains of pollen and penetrating the flower's stigma, the receptive part of the female reproductive system. This sets the stage for They are also incredibly low-pitched, more typical of an animal the size of fertilization of the egg and would begin the process of seed formation -- an elephant. Size is related to pitch in that the dimensions of the laryngeal had the reproductive act been completed. vocal folds normally constrain the lowest frequency that an animal can generate. As a result, smaller species will typically give calls with higher "In Cretaceous flowers we've never before seen a fossil that shows the frequencies than larger ones. pollen tube actually entering the stigma," said George Poinar, Jr., a professor emeritus in the Department of Integrative Biology at the OSU Koalas have bypassed that constraint by putting those vocal folds in a College of Science. "This is the beauty of amber fossils. They are new location. Charlton describes the folds as two long, fleshy lips in the preserved so rapidly after entering the resin that structures such as soft palette, just above the larynx at the junction between the oral and pollen grains and tubes can be detected with a microscope.” nasal cavities. They may not look all that different from the laryngeal vocal folds of other mammals, but their location is highly unusual. The pollen of these flowers appeared to be sticky, Poinar said, suggesting it was carried by a pollinating insect, and adding further "To our knowledge, the only other example of a specialized sound- insights into the biodiversity and biology of life in this distant era. At that producing organ in mammals that is independent of the larynx are the time much of the plant life was composed of conifers, ferns, mosses, and phonic lips that toothed whales use to generate echolocation clicks," cycads. During the Cretaceous, new lineages of mammals and birds Charlton says. were beginning to appear, along with the flowering plants. But dinosaurs still dominated the Earth. The combination of morphological, video, and acoustic data in the new study represents the first evidence in a terrestrial mammal of an organ "The evolution of flowering plants caused an enormous change in the other than the larynx that is dedicated to sound production. Charlton says biodiversity of life on Earth, especially in the tropics and subtropics," that he and his colleagues will now look more closely at other mammals to Poinar said. find out whether this vocal adaptation is truly unique to koalas. ______January/February 2014 - 6 THE WORKING WORM http://riaus.org.au/articles Helen Dockrell

The Environmental Enthusiast So why not chuck a few pasture earthworms into your garden? It could be a good idea, but not if you compost your dinner left-overs. There are species of earthworm that feed on organic matter rather than soil, and these are the ones you'll find in your worm-farm. They're great for processing left-overs and releasing nutrients in a bio-available form, but won't necessarily thrive in pastures. These are the same earthworms used to reduce the environmental impact of landfill by digesting the organic components like left-over food. Addition of earthworms to landfill sites creates 13,000 cubic meters of landfill space in Australia every year. To top it off, when the earthworms die, they decompose rapidly and release bio-available nitrogen. What champs! Maybe you fish with them, maybe there are a few chilling out in your backyard. Ever wonder what prospects an adventurous young worm Recent Australian research finds that the use of earthworms as a filter in might consider, though? Whilst the term “vermiculture” speaks more to the water recycling process can increase the purity of recycled water. most of pasta than biotechnology, it turns out that the humble worm is This is due to earthworms being able to retain a number of different the industrious worker behind many modern developments. chemicals from wastewater. The biological filtering of water by the earthworms also prevents the production of heavy metal and complex The Farmer organic “sludge” which is a by-product of the current water-recycling Earthworms are known to be great for your soils but as many species of system. earthworm process food in their own ways it's important to know which ones are most useful for agricultural versus composting needs. It has The Scientist been commonly accepted for some time that healthy soil has a few The earthworm's roundworm cousin, Caenorhabditis elegans, can also worms wriggling around somewhere in it, but it took New Zealand's be found in worm farms but also dwells in the scientific laboratory. This bizarre “patchiness” of earthworm population to really unveil the extent scholar adds to countless genetic and biochemicals studies daily as a to which earthworms improve crop and pasture productivity. model organism. It has proved simple to study in a developmental sense, and it was the first organism to have its genetic code completely Early settlers in New Zealand introduced foreign earthworms sequenced. This means that scientists can study the action of individual accidentally by bringing along potted plants and replanting them in New genes in C. elegans and work out what they effect at every simple stage Zealand soil. As a result, New Zealand now has particularly pronounced of development. This is in contrast to, say, humans, where a tiny genetic areas of “exotic” earthworm habitation. It's these areas with an change can come into effect at any stage of life, affect any number of increased variety and number of earthworm that produces pastures that other biological happenings, and be entirely undistinguishable from support much more livestock. The natural movements and life cycle of other parts of human biology we don't yet understand. these earthworms significantly betters the soil quality, allowing grasses and shrubs to thrive and livestock to be supported more successfully. In From pastures to backyard compost heaps, in modern environmental addition, it was found that the weight of the earthworms inhabiting the concerns and genetic advances, worms are doing a pretty fantastic job. pasture was approximately equal to that of the livestock above-ground. Makes me look at the inhabitants of my pot plants differently… That's right, the same weight of worms as sheep. Mind-boggling. Feature image “Earthworms” from Flickr authored by Amit Patel. For those playing at home the average sheep weighs about 70kg, and it Body image 1 “Earthworms mixing soil” modified from Australian Earthworms as a Natural takes about 2000 adult earthworms to make 1kg. So for every sheep you Agroecological Resource authored by R.J. Blakemore and M. Paoletti. have 140,000 earthworms! Body image 2 “CrawlingCelegans” from Wikimedia Commons authored by Bob Goldstein.

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