YOUR ALERT TO NEW AND EMERGING THREATS

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1 Message from the CEO SEPTEMBER > It s that time of year Weed Watch Events News I d like to start by thanking everyone who attended or presented at the 2012 Vegetation Managers Forum last week. This industry event had a fantastic response on the day, and I believe it speaks volumes about where our industry is headed; that there are so many within it who are proactive about attending events to generate and share knowledge. I look forward to seeing all of you (plus some new faces) at the 2013 event, so keep your eye on The Vegetation Manager and your inbox for a date claimer. Moving forward we have committed to utilising this publication to distribute more of the valuable information raised at these types of events on critical topics such as glyphosate resistance and Myrtle rust. Currently there are more than a million family owned businesses in Australia - Technigro is very proud to be one of them. Soul Stories recognises 100 great Australian family businesses. Technigro is proud to be one of only two Gold Coast business featured in the book. If you would like to read ours, or any of the inspirational stories that feature in Soul Stories please contact Tara Looby (tara.looby@technigro.com.au) for a copy. Finally I would like to highlight the importance Technigro places on building strong partnerships with our customers. Since starting the company 25 years ago, our team has worked hard to foster a culture which encourages relationship building and trust. Recently we entered into an agreement that will see Technigro manage the vegetation throughout the Brisbane region road network. We have proudly been working in partnership with Brisbane City Council for the past 15 years and this agreement forms the latest chapter in this long standing relationship. Until next month, take care & stay safe. Warm regards, Nick Bloor It s that time of the year Seasonal Weeds Time to target Crowsfoot again Crowsfoot (Eluesine indica) is a common weed of lawns and playing fields and competes aggressively with turf species. September is the ideal time to start targeting this aggressive weed with a pre-emergent program. Learn more about Crowsfoot by reading our factsheet ON PAGE 5 or talk to Justin Sands our turf specialist on YOUR ALERT TO NEW AND EMERGING THREATS Himalayan ash Himalayan ash Himalayan ash is a small tree of the Oleaceae plant family that is native to the Indian subcontinent, China and south-eastern Asia. It has been widely planted as an ornamental tree in Australia in the last thirty years and is beginning to spread from plantings into bushland areas in south-eastern Queensland. Learn more on page 6 and 7. Page 1

2 Upcoming Events > 18th Australasian Weeds Conference Developing Solutions to Evolving Weed Problems. 8th - 11th October 2012, Melbourne, VIC. > 9th Australian Network for Plant Conservation (ANPC) National Conference Achievements and Future Directions 29th October - 2nd November 2012, Canberra, ACT. > ALGA - The National Local Roads and Transport Congress Delivering your Agenda 14th - 16th November 2012, Hobart, TAS. Fast Facts > In South East Queensland the average daily maximum temperature in winter is 20 degrees Celsius while the average daily minimum temperature drops to 9 degrees Celsius. > The lowest recorded minimum temperature in Queensland was recorded at Stanthorpe on the 4th of July 1895, it was minus 11 degrees Celsius. > The highest recorded maximum temperature in Queensland was recorded at Birdsville on the 24th of December 1972, it was 49.5 degrees Celsius. In the news Vegetation Managers Forum explores industry s most pressing issues The Vegetation Managers Forum held on Tuesday the 28th of was a major success for the industry, with a strong turnout and great interaction amongst the delegates and with speakers. This year s Forum featured a series of presentations from high profile speakers in the field, including Dr Christopher Preston from the University of Adelaide, and Dr Suzy Perry from the Department of Agriculture, Fisheries and Forestry. Dr Preston presented the results of the most resent RIRDC study that explored the issues surrounding glyphosate resistance in non-agricultural areas. This presented a number of issues and recommendations that where relatable to most within the SEQ vegetation management community. Dr Perry then presented an update on the devastating Myrtle rust fungus that is rapidly becoming a major threat, which informative, well received and provoked many questions. Myrtle rust is paralysing the Myrtaceae family and is a problem being faced by most landholders. Dr Sheldon Navie, who completed his doctorate at the University of Queensland, produces a monthly Weed Watch publication that outlines new and/or spreading weed threats in Australia. At the Forum, Dr Navie took the opportunity to produce a Where are they now? presentation, which provided an update on the statuses of all of the weeds he has profiled thus far. Copies of each guest speaker s presentation can be found on the Technigro website. Dr Preston was then joined by fellow resistance experts Dr David Thornby and Dr Jeff Werth from the Department of Agriculture, Fisheries and Forestry as well as Dr Mark Walker from Syngenta and Technigro s Dr Sheldon Navie for a facilitated discussion. This allowed delegates access to the experts who were able to fully explore the the issues of resistance. The discussion highlighted what a major issue resistance is for vegetation managers and landholders. Given the interest around glyphosphate at the Vegetation Managers Forum, Technigro CEO Nick Bloor has committed to using the company s resources to build awareness about the problem. The response generated by the Forum was overwhelmingly positive, and has inspired the creation of other knowledge sharing platforms for the industry. Technigro are pleased to be able to host the Vegetation Managers Forum each year, and as the premier industry event in SEQ we are looking to providing a repository of information for the industry that will provide a simple, comprehensive and cost effective data source. Technigro are taking submissions on what industry members would most like to see in such a resource. In order to have your say, please Tara Looby at tara.looby@technigro.com.au Page 2

3 Turfgrass Diseases - by Dr Kate Entwistle Nature does not work with pure cultures. I suspect that many plant diseases are influenced by associated organisms to a much more profound degree than we have yet realised... Fawcett These words were written almost a century ago and are, in my opinion, certainly as valid today as they were back then. When I started to look at plant diseases in the early 1980s, I did what most people do and read the current textbooks and believed (somewhat naively) that this was the whole truth. That, if I understood these texts, I would understand everything I needed to know about turf disease. Age and experience are amazing things - age maybe not so much - but with age you develop the confidence to say what you believe, based on your experiences. Having specialised in turfgrass diseases for nineteen years, I have continually updated my views on certain aspects of disease development and one of the more important developments that I believe is affecting an increasing number of amenity areas, is the association of fungal and plant parasitic nematodes in the development of disease. In this article, I would like to share my thoughts on turfgrass disease development and summarise some of the published information that is available on similar pathogen interactions in agriculture. First of all a brief summary of the two individual groups of pathogens. Fungi: a complex and diverse group of organisms which require organic substrates from which to obtain energy for growth and development, contain a chitinous cell wall, generally grow as multi-cellular filaments (hyphae) forming a mycelium, complete sexual and/or asexual reproduction via spores and, perhaps quite surprisingly, are more closely related to animals than they are to plants. In the turfgrass situation, the method by which they obtain their organic substrates from the plant varies, but most of our fungal pathogens can live quite happily as saprophytes on dead or decaying material and are, therefore, more correctly referred to as facultative parasites. Nematodes: the second largest and most diverse group of animals (after insects) that have adapted to virtually all environments on the planet. They are unsegmented roundworms with a complete digestive system, pass though several moults to enable their development to mature male or female, reproduce via eggs, have a simple nervous system but limited circulatory and respiratory systems and, so, breathe via diffusion of oxygen through their body. Plant parasitic species tend to be microscopic and even the larger ones are difficult to see without a microscope due to their body being transparent. They feed on the cell content of their chosen host and alter the physiology of the host to ensure that their food supply is maintained. Plant parasitic nematodes are obligate parasites. situations where both fungus and nematode are associated with plant disease, which came first? In 2002, Back et al published a comprehensive review article looking at diseases in cultivated crops and the complex interrelationship between host, pathogen and prevailing environmental conditions. We have known for a long time that plants are rarely, if ever, subject only to the influence of one pathogen but that, with regard to soil pathogens in particular, there is massive scope for interaction between the different microorganisms. We often observe so-called synergistic effects when two pathogens are involved in disease development. This means that, when working together, the two pathogens can cause greater damage to the host than their combined individual effects would ever cause. The first recorded case of a fungus-nematode interaction was made by Atkinson in 1892 who noticed that fusarium wilt of cotton (caused by the fungus Fusarium oxysporum) was more severe when the plants were also affected by root-knot nematodes (Meloidogyne). Since this early observation, similar interactions have been recorded between fusarium wilt pathogens and rootknot nematodes in several host crops and, more importantly perhaps, between the Root-knot nematode and other soil-borne fungi including Rhizoctonia solani. The Root-knot nematode, Meloidogyne sp., is a so-called sedentary endoparasite in which the infective juveniles establish specific and permanent feeding sites around the phloem of infected plants. These nematodes are thought to secrete enzymes and growth regulators that cause this distinct change in plant morphology. In addition, they secrete compounds in to the plant via their salivary glands that affect the plants photosynthetic ability and relocate the products of photosynthesis directly to the specialised feeding sites. In this way, the nematodes are ensured a continued supply of nutrient but the plant is subject to increasing stresses as its nutrient supply is depleted. Ectoparasitic nematodes do not establish such close feeding associations with the plant but graze the roots by feeding for different periods of time from individual plant cells before moving on. They tend to cause much less damage to the roots general morphology and, possibly for this reason, the number of associations that are recorded between ectoparasitic nematode species and fungal disease are much less. That said, certain species can cause a dramatic branching of root development due to their repeated activity around new knot tips, and the root symptoms that develop are characteristically excessively branched. Another endoparasitic nematode that is often associated with fungal disease is the Lesion nematode Pratylenchus. This nematode migrates through plant root cells as it feeds and causes a breakdown in root structure, separating the outer cortical cells from the inner stele (xylem & phloem). With the loss of root structure, water and nutrient uptake and movement is impaired but, also, the resulting damage to the structure allows easy access by certain fungal pathogens. Therefore, it can be argued that plant parasitic nematodes need a healthy plant host on which to feed and fungal pathogens (generally) need a weakened plant host as a food source. In It is not only the entry points of plant parasitic nematodes in to the roots that produce regions that can be further colonised by fungi, but when females from species like the Root-knot and Cyst Page 3

4 nematode break through the root tissues to deposit their eggs or to mature (encyst), they cause massive rupturing to the roots which can allow easy entry of fungal infections. There is research to suggest a possible systemic effect of parasitic nematodes in certain host plants, and that nematode infection can, in some way, also decrease a plant s resistance to fungal infection. Over the past three years I have received turf samples for analysis from areas that have shown symptoms of atypical fungal disease. The timing of the disease development may have coincided with when the disease could be expected to develop, but the damage to the sward has not followed the typical pattern of disease development. In other cases, regardless of the timely application of plant protection products, symptoms of fungal disease (especially Microdochium patch, Anthracnose diseases and Take-all patch) have continued to develop and show a niggling infection through the turf. In all of these cases, the rootzones have been found to support high populations of plant parasitic nematodes. With documented evidence of several nematode-fungal disease developments in agricultural systems, we know that there is a real possibility that this can also be happening in turf. It makes sense and, generally when things make sense, they are worth taking seriously. I will continue to look for possible associations, and hopefully future research will prove or disprove what this gut-feeling would certainly suggest to be true. Dr. Kate Entwistle, The Turf Disease Centre kate@theturfdiseasecentre.co.uk Registrations Open for 18th Australasian Weeds Conference The Australasian Weeds Conference is being held in Melbourne from the 8th to the 11th of October. The conference will showcase recent advances in weed science, extension and policy across Australian and international communities and landscapes. The program will provide valuable information and networking opportunities for anyone with an interest in aspects of weed legislation and development of practical solutions to evolving weed problems. For more information about the event, or to register, visit Page 4

5 WeedWise CROWSFOOT Eleusine indica June 2010 Description & life cycle Crowsfoot (Eluesine indica) is a Summer growing grass that tolerates close mowing and compacted wet or dry soils. Crowsfoot competes aggressively with turf species and germinates in spring after rain when temperatures reach 15 C - 18 C. Crowsfoot gains its name from the way the leaves angle from the stem, making it look like crows feet. Reaching up to 50cm in height, Crowsfoot has a very strong, fibrous root system and is a coloniser of bare or disturbed areas. The stems are upright to sprawling and can form a mat, however they do not make root at the nodes. The seed head consists of several short, finger-like branches radiating from the top of an erect stalk. Leaves are shiny, green and hair free. They can be up to 9cm long. Crowsfoot has been recorded to produce up to 60,000 seeds per plant. These seeds will not germinate until soil temperatures are in the C range. In optimum conditions, the time between germination and flowering is approximately 5 weeks. Key features > Is a common weed of lawns and playing fields, where the grass cover is thick or has been disturbed during Winter. > When matured, it forms thick clumps that disrupt the surfaces of playing fields. > Normally infests turf and over 40 crops throughout tropical areas of the world. Control 1. Small clumps can be chipped out or removed by hand, although mature plants have a strong, fibrous root system that resist removal. 2. An effective management strategy is to improve turf-growing conditions by alleviating soil compaction and reducing excessive moisture. The current turf registration for pre-emergent controls in Australia includes Pendimethalin, Dithiopyr and Oxidiazon. These herbicides should be applied when soil temperatures at 10cm deep average 15 C for 24 hours. This is usually from early August to September. 3. The clumping nature of this weed significantly impacts on the safety and usability of the sporting surface or park. Post emergent control can be achieved with repeat applications of Diclofop-methyl. Diclofop-methyl is most effective on Crowsfoot in temperatures below 24 C. This means a narrow window of opportunity to treat in early spring and early Autumn. Your Provider of Vegetation Management Solutions Post: PO Box 2038, Burleigh BC, QLD 4220 T: for smarter solutions Page 5

6 SEPTEMBER 2012 TM YOUR ALERT TO NEW AND EMERGING THREATS Habit of tree in fruit. 2. Leaves and cluster of small white flowers. 3. Immature fruit with papery wings. 4. Seedling with rounded leaflets. Himalayan ash (Fraxinus griffithii) TREE Introduced Not Declared Himalayan ash is a small tree of the Oleaceae plant family that is native to the Indian sub-continent, China and south-eastern Asia. It has been widely planted as an ornamental tree in Australia in the last thirty years and is beginning to spread from plantings into bushland areas in south-eastern Queensland. Distribution Himalayan ash is commonly grown as a garden and street tree in Australia, and has been recorded becoming naturalised in south-eastern Queensland in recent years. There have only been a few herbarium records of naturalised plants from the Sunshine Coast/Wide Bay area in the last 5 years. However, numerous sightings of younger plants have also been made in other parts of south-eastern Queensland (i.e. in Brisbane and on the Gold Coast). Description Himalayan ash is a small tree usually growing less than 10 m tall, and unlike most other ash trees it does not lose its leaves during winter (i.e. it is evergreen). The main trunks of older trees are covered in a mottled green, brown and cream bark. Its leaves (10-25 cm long) are arranged in pairs along the stems and are borne on stalks 3-8 cm long. They are compound, with 5-11 leaflets, and these bright green and glossy leaflets (2-10 cm long and 1-5 cm wide) have entire margins and pointed tips. However, seedlings have almost rounded leaflets and their leaf stalks are slightly winged. The small white flowers are arranged in branched clusters (10-25 cm long) at the tips of the stems. They have four tiny sepals (about 1 mm long), four white petals (about 2 mm long) and two yellow stamens. Flowering occurs mainly during summer (i.e. from December to February in Brisbane). The winged fruit (i.e. samaras) are initially green, but turn pinkish and then brown as they mature. These fruit (about cm long and 4-5 mm wide) contain a single seed and are mainly present during summer and autumn (i.e. from January to May). Quick Facts > A small tree growing up to 10 m tall > Compound leaves with 5-11 leaflets > Tiny white flowers borne in dense clusters > Seeds with a papery wing cm long Habitat This species is a potential weed of urban bushland, forest margins, riparian vegetation, open woodlands, roadsides and disturbed sites. Most young plants have been found growing along waterways, near the margins of urban bushland areas, or along internal roads or tracks within bushland reserves. Documented distribution Potential distribution Technigro Australia Pty Ltd 2012 Page 6

7 SEPTEMBER 2012 TM YOUR ALERT TO NEW AND EMERGING THREATS Young Himalayan ash tree growing in bushland area. 2. Mottled bark on main trunk. Reproduction and Dispersal Himalayan ash reproduces mainly by seed, but will also spread laterally via root suckers. The winged seeds are mainly dispersed short distances by wind in the first instance, but can also be spread longer distances by water or in dumped garden waste. Why is it an Emerging Threat? Large numbers of seedlings are often seen growing under adult trees of this species, and its windblown seeds are easily dispersed into nearby natural habitats. For example, at Maleny on the Sunshine Coast it has been recorded spreading from plantings into nearby rainforest areas. It has also been observed growing in shaded riparian habitats along Enoggera Creek in the northern suburbs of Brisbane. Once it becomes established in these areas, it has the potential to compete with and replace native species. Look a-likes Himalayan ash is similar to another weedy introduced species known as narrow-leaved ash (Fraxinus angustifolia). However, the leaves of Narrow-leaved ash have toothed margins and are shed during winter (i.e. it is deciduous).this species is also mainly found in the temperate regions of southern Australia. Control Methods Seedlings and younger plants can be removed by hand. Larger plants can be manually removed with the aid of suitable tools, but attention must be taken to remove the entire crown. There is no information readily available on the control of Himalayan ash with herbicides. However, woody environmental weeds are able to be controlled in Queensland with some herbicides as outlined in APVMA off-label Permit (see gov.au/per11463.pdf). For example, triclopyr + picloram, fluroxypyr and 2,4-D may be applied as a foliar spray directly to the target plants. Alternatively, other formulations of these same chemicals and formulations of Glyphosate can be applied as a cut stump or basal bark application. However, plants growing along waterways should only be controlled with herbicides that have an aquatic registration (e.g. Round-up Biactive or Weedmaster Duo). Please read the off-label permit carefully for the exact products and rates to use and, unless otherwise stated in the permit, the use of any of these herbicides must be in accordance with the instructions on their labels. Within other state boundaries, it is recommended that any relevant permits or government legislation applicable to the region be consulted. Top. Habit of Narrow-leaved ash. Bottom. Narrow leaflets with toothed margins. The control methods referred to in Weed Watch should be used in accordance with the restrictions (federal and state legislation and local government laws) directly or indirectly related to each control method. These restrictions may prevent the utilisation of one or more of the methods referred to, depending on individual circumstances. While every care is taken to ensure the accuracy of this information, Technigro does not invite reliance upon it, nor accept responsibility for any loss or damage caused by actions based on it. This information has been developed with the assistance of Dr Sheldon Navie. Photographs are also courtesy of Dr Sheldon Navie Technigro Australia Pty Ltd 2012 Your Provider of Vegetation Management Solutions Post: PO Box 2020, Nerang BC, QLD, 4211 T: technigro.com.au for smarter solutions Page 7