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Newsbits
April 2010
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Visitors Welcome.
Next
Meeting:
Friday, 9th April
7.30pm for 8.00pm start.
*Venue:
Horticultural
Research Station, Research Rd., Narara
*Guest
Speaker:
Tim E.
Speaker for April Tim E. Tim has worked as a scientist and senior manager in botanic gardens for close to 20 years and is currently Executive Director of the Botanic Gardens Trust in Sydney and responsible for the Royal Botanic Gardens, The Domain, Mount Tomah Botanic Gardens and Mount Annan Botanic Gardens. Hi is author of many scientific publications and is a regular contributor to the ABC Sydney radio and website, and writes for a variety of science, nature and garden magazines. In 2007 Tim was appointed the 12th NSW Government Botanist, an honorary position dating back to 1817 and he is an Adjunct Professor in the School of Biological Sciences at The University of Sydney. On the night Tim will be talking about the seasons and why should there be just four.
Speaker for March Wendy is doing a masters by research degree through University of NSW as part of a bigger project that is looking at whether Bush Rats Rattus fuscipes can be used as a biological control against the introduced black rats Rattus rattus. Wendy’s research concentrates on looking at whether bush rats use weedy edge habitats with the main focus on lantana.
Working as a zookeeper
in the nocturnal section at Taronga Park for 20 years Wendy looks
after the native rodents. When walking through the park Wendy is
regularly asked for directions to the Koalas, Elephants, Wombats and
other high profile animals but nobody in all her 20 years has ever
asked directions to the Plains Rats and she is just hanging out for
that day. Over 60 species of native rodents exist in Australia, they don’t get much PR yet they are so important. They are at the base of the food chain and perform all sorts of important roles. The black rat which is the feral species, and the bush rat (pictured right is the Kincumber Rat) are of similar size and have similar habits and it has been shown from recent research that the bush rat is socially dominant and will actually kick the black rat out. The plan for the bigger project is to eradicate the black rat using the Mosman area as a test case and re-introduce the bush rat into remnant bushland areas. Hopefully the bush rat will prevent re-invasion by the black rat and further research has shown that whichever species takes the ecological advantage that species is the one that will prevail.
In Australia there are
three classes of mammals. We have the Monotreme which is the egg
laying mammal such as the duck-billed platypus or echidna; we’ve got
the marsupial – koalas, possums and antechinus, and we’ve got the
placental mammal. Humans are placental mammals, bears and
carnivores are placental mammals and rodents are placental mammals
and that includes our native rodents. They are not marsupials
they’re a true rat but a native one that has spent the last million
years or so evolving here in Australia. Our native rodents range from the water rat which is the largest, and most of us know the water rat they have tiny beady eyes and a white tip on the end of their tail. They are actually very smart, a friend has trained water rats on an exhibit at the zoo to weigh themselves and at the end of the show she actually trained them to pull on the string that brings down the scroll that ends the show. Then there’s the tree rat a northern species from up the top end and a personal favourite they are like a native squirrel and there’s the black footed tree rat which also has the white tip on their tail. They have a slower reproductive cycle and feed on fruit and nuts and are important in re-establishing cleared areas. They will actually bury their food so are quite important to the eco system. Then we have the little hopping mouse with back legs like a kangaroo.
Of course we also have
the introduced
In the bush you will
most likely come across a bush rat or a swamp rat whilst anything in
your house is likely to be a black rat or possibly a brown rat. The
black rat has a really long tail, significantly longer than its head
and body, and is the one that is most likely to inhabit your roof.
The bush rat can climb but they’re quite awkward and not likely to
take up residence in your roof. The black rat will form colonies;
they carry disease and will take advantage of human habitation and
all the food and resources that we can provide where the bush rat
doesn’t carry the bad diseases. They are fungivores and feed on
fungi so actually help to spread the mycorrhizal fungi which is the
fungi that shares a symbiotic relationship with plants stabilising
the soil and helping them to take up nutrients. The brown rat is
extremely aggressive if you should trap a rat and it tries to attack
you it would be the brown rat because the black rat tends to be a
bit timid. The antechinus (Pictured right) is a marsupial which is related to the Quoll and Tasmanian devil, they’re a carnivorous marsupial and have a shorter tail that’s less than the head and body length, a pointier nose and serrated teeth. The male antechinus lives for just one year. Towards the end of that year the breeding season comes along and they will mate with as many females as they can, the steroids build up in their system and they all die from exhaustion. The black rat and the house mouse are more likely to appear during the day than the bush rats which seem to be more nocturnal and the same applies to the antechinus. So looking at edge effects – an edge is an intersection between two different eco systems; it could be a forest abutting a grassy area or where a road or power line is going through an area creating an edge where the forest meets up to the cleared area. Wendy is specifically looking at how bush rats interact in the suburban bushland interface and particularly where there’s lantana and asks the question ‘do the bush rats come down to those edges and do they use weedy edges?’ There are all sorts of edge effects the obvious one is habitat clearing which leads to a difference in light levels and there are indirect effects such as predation effects where animals are going to be more wary of using an area. It might be that they are more likely to be seen there, there could be more cats and dogs there or it could even have the opposite effect because in a cleared area they have really good vision and can see the threats around. Structurally lantana is very dense and can physically out-compete all other vegetation. A paper exists suggesting that it may be allelopathic which means that it will chemically suppress other plant species. So will the bush rats with their preference for a complex understorey use the lantana or avoid it? There’s a suggestion that lantana changes the composition of fungi in the soil and bush rats are dependent on the mycorrhizal fungi. Bush rats thrive where there’s been disturbance and the growth of lantana is often an indication of disturbance. We know that lantana is toxic to stock and it suppresses reproduction in rattus species but it could also be toxic to bush rats. Wendy is trapping in three different natural habitat plots; she’s found weedy edges at the back of Rumbalara and there is lots of lantana growing near the housing estates around Kincumba Mountain and lots of disturbance. For the sake of comparisons she has a pristine bush area in the middle of Brisbane Water National Park kilometres away from any edges. She also has trapping sites that are in the middle of the National Park or in the middle of the bush away from any edges but where there’s a big clump of lantana. If there are differences in the bush rat population in any of the sites it could be that they are responding to the edge effects like cats and dogs and disturbance where there’s human habitation or to the weeds that are there like lantana. One of the main edge effects is the growth of weeds. Inside the traps they place some non-absorbent cotton wool that is especially imported from America at $40 per roll and it keeps the trapped animal dry and warm even if it’s pouring with rain. To attract the animal they place a peanut butter ball inside the trap and when the rat runs into the trap it triggers the door trapping it inside. Fifteen traps are set in a straight line at 15m intervals at each site. Before releasing the animal a small piece of fur is clipped from its left flank and a small cotton ball attached with glue to its rear end. One end of the line is attached to a stick enabling the line of cotton to be followed the next day. Generally the line will go for120m-130m before it runs out but around the 70m mark the little rat gets frustrated with this cotton ball stuck to its rear and rips it off and shreds it like in a little temper tantrum. Following the line at every 15m measurements are taken of the vegetation; what type of micro habitat they’re actually choosing to go through, and then from a random compass bearing a straight line is run. When this is replicated many times over it starts to produce some meaningful data. . Before the actual trapping is done the traps are set and turned upside down so that the door will not trigger and trap the animal and gets them used to visiting the traps and feeding on the peanut butter ball. The trapping is done over three nights and it seems that the rats go off and tell all their friends because so many turn up on the second and third nights with plenty of the rats re-captured. Wendy is only half way through the research and is finding that she is not trapping many bush rats at the edge sites. The numbers trapped at the edge sites and the weedy sites are quite similar so it appears that yes, they are using the lantana. While the traps are upside down they are also visited by black rats, they will go in and take the whole bait and leave no droppings inside the trap. However, when the traps are turned around somehow they know and won’t go in; they appear to be quite smart. Very rarely is a black rat trapped. If a lot of males are trapped at an edge site it would indicate that the site was poor habitat because the females tend to be socially dominant over the males so if the site is full of young males it is probably because they have been kicked out by the females. Bush rats are mostly sedentary; the females will hang around where they were born while the males will rove around a home range of about 100m2. To analyse how safe the rats are feeling in a particular environment a little tray of sand in which peanut fragments are buried is placed in the middle of the site. The theory is if the animal feels really safe they will spend a lot of time foraging, they’ll take the easy bits first and then dig down and find the buried fragments at the bottom taking all the food before departing. In a risky environment they’ll quickly grab the easy bits and retreat and when the remaining food is weighed it’s found that most of it has been left. To compare in which environment they feel safer a tray is put in the middle of a lantana thicket and another tray placed in the middle of a native bush thicket similar in density to the lantana. This will show whether they feel safer in the lantana or in the native vegetation. In the future Wendy will be putting out some infra red cameras to see where the black rats are the densest to see if that’s what is driving the bush rats away.
Specimen Table Presented by Ian S.
This is the time of
the year when most Banksias start to produce their brushes and not a
lot of other plants are flowering. This month we had
Banksia
integrifolia which can grow into a tree up to 15m high and
produces yellow brushes mainly in autumn and winter but tends to
flower throughout the year.. Known as the Coast Banksia it is
tolerant of salt spray and is easily recognised by its leaves which
are silvery underneath. Banksia
spinulosa grows to
about 2m high and is also tolerant of salt spray. It bears long
spikes of yellow/orange flowers in autumn and winter which birds
find attractive. Myoporum ellipticum (at right) is a plant that can be prostrate or grow into a shrub about 1.5m high. The leaves are thick and fleshy and the white flowers with purple spots appear from spring to summer. Ian brought along a Waratah bloom from his garden from a plant that has about 40 flower heads. This is a hybrid Telopea ‘Emperors Torch’ with a dark red flower which is not as compact or more open than our local species T. speciosissima and oddly enough is flowering in autumn. Helichrysum apiculatum or Yellow Buttons is a suckering ground cover with silvery-grey foliage and clusters of bright yellow flowers that appear in spring and summer. Likes a sunny spot in the garden and can be propagated from cutting. Hibbertia scandens is a vigorous vine that bears large bright yellow flowers during most months of the year followed by red fruits. The plant is easily grown from cutting and can also be grown from seed. The flowers are the largest of the Hibbertia species.
Scaevola aemula
has many forms with a lot of hybrids being available on the market.
Scaevola
‘Purple
Fanfare’ and S. ‘Mauve
Clusters’ are recommended hybrids and will flower for most of
the year. However, they have a tendency to drop dead overnight
towards the end of summer so regular cuttings need to be taken so
replacement plants are on hand. Brunoniella australis (at left) is a low growing plant that bears large mauve-blue bluebell like flowers each one lasting for just the one day and they appear most months of the year. It grows and flowers well in a shady area and strikes readily from cutting. However, BEWARE this lovely little ground cover can take over an area if the conditions are right. Gymnostachys anceps common name Settler’s Flax is a tufted herb found in rainforest which farmers used the leaves as cord or string. The flowers are small and appear on the slender spikes of the plant and are followed by large blue shiny drupes. This plant can be found at Katandra Reserve. Grevillea ‘Superb’ is a hybrid with the same parentage as G. ’Robyn Gordon’. It grows to 2m high with a similar spread and bears orange flowers throughout the year that attract many birds and bees. It responds well to hard pruning and is propagated from cutting. Other plants making a return appearance this month were Correa ‘Dusky Bells’, Trema tomentosa and Orthosiphon aristatus or Cats Whiskers. Information sources - Fairley & Moore Native Plants of the Sydney District, Robinsons Field Guide to the Native Plants of Sydney and Wrigley & Fagg Australian Native Plants.
The Sydney Rainforest Ourimbah Wholesale Nursery is holding a plant sale over the Easter long weekend Friday 2nd until Monday 5th April.
If you see these
maggots feeding in your compost heap or bin don’t be alarmed soon
they will turn your waste into rich earthy castings that make a fine
soil conditioner. The Black Soldier Fly bears a strong resemblance to a wasp however a fly is distinguished by its one set of wings whilst a wasp has two sets. The adult Soldier Fly does not eat vegetable matter and will not attempt to enter the home and unlike the common house fly it does not eat waste nor do they regurgitate onto food. They do not bite or sting and they do not transmit disease. The female adult lives for 5 to 8 days and during this time will produce up to 900 eggs. These are generally laid close to waste and take about 5 days to hatch. The maggots start out white and are about 20-25mm long and in ideal conditions where food is plentiful they can reach maturity in about 2 weeks. In the absence of food or if the weather is cool they can take up to 6 months to reach maturity.
The
larvae, being maggots, have an image problem as most people associate
them with bacteria which generate a feeling of revulsion. As a
result the pet food industry markets the larvae as Phoenix Worms and
they are used for live food for fish, frogs, birds and reptiles. In the worm farm or compost bin the larvae will multiply much faster and vigorously devour and recycle a lot more vegetable matter than the worms without any discrimination and unlike worms that need cool conditions the soldier fly larvae can sustain extremely hot temperatures. Like worms they emit no odour. The common house fly and blow fly larvae are also capable of breaking down vegetable matter at a fast rate in the compost bin but the use of those maggots will put you in touch with some of nature’s disease carriers. Another valuable attribute is that these larvae can also effectively dispose of problem waste such as offal, dairy waste, feathers, fish scales, etc., by converting this waste into earthy smelling manure that makes a fine soil conditioner. Soldier Fly larvae are an excellent addition to the compost bin. Source of Information – Website www.microponics.net.au/?p=175 & A field Guide to Insects in Australia byPaul Zborowski and Ross Storey
On the 2nd May the Australian Plants Society together with the Environmental Trust and Gosford City Council will be launching a guide on the long stem planting method. A field demonstration will take place at Katandra and morning tea will be provided. This is a free activity helping to promote the use of deep planting in bush regeneration and Landcare sites so come along and join in on the day. Bookings are necessary for catering purposes - contact Audrey on 4323 3986 by the 23rd April to book your place.
March Bushwalk The weather was perfect for a walk in Brisbane Water National Park and about 15 members and 2 visitors gathered in the picnic area at Girrakool to explore one of the loop tracks that we hadn’t walked in the past.
Girrakool Waterfall Epacris pulchella The track doubled back towards the entrance to the park and led us to a lookout overlooking a small waterfall which was inaccessible to most of us it being steep and slippery. There were plenty of ferns to be seen including Gleichenia rupestris and Sticherus species. Not a lot of plants were in flower but we did manage to find our local emblem Epacris longiflora, a deep pink specimen of Epacris pulchella, Persoonia isophylla and Boronia anemonifolia all in flower beside the track.
The loop took us back
to the track down to the main waterfall where
Leptospermum
squarrosum was flowering. Other plants that we saw along the track
that were not in flower were Leptomeria
acida the native
currant and Leucopogon
amplexicaulis with its interesting
stem clasping foliage and Tristaniopsis
laurina was prominent
around the waterfall. Goanna
Epacris longiflora
It was getting close to lunchtime so we headed back up to the picnic area and enjoyed lunch at one of the picnic tables in the area with a Goanna on a nearby tree posing for the many photographers there on the day. Other fauna sighted during the walk included a red-bellied black and of course the ever friendly leeches.
Fungi Dates For Your Diary
Organic Matters Special Mark’s Plant of the Month is Viminaria juncea, Golden Spray or Native Broom. Viminaria juncea occurs naturally in Hanging Swamps and Paperbark Woodlands and prefers a moist site over a dry one. It can grow in sandy soil but also likes heavy clay soils.
Meeting Place: Banksia Car Park, the upper car park in Strickland S.F.
Directions:
To get there, turn left off Mangrove Road in Narara and follow the
fire trail. We will leave some cars at the lower Stoney Creek
carpark for our return.
Pellaea paradoxa Hymenophylum cupressiforme Description: The walking track passes downhill, past rocky cliffs and boulders sheltering ferns - Pellaea paradoxa, Hymenophyllum sp., Polystichum sp. and several species of Asplenium, Adiantum and Blechnum. The subtropical rainforest vegetation includes Cryptocarya (Brown Beech), Sassafras and Bolwarra (Eupomatia laurina) and Diospyros australis (Black Plum). The track finally descends to the creek, where more ferns line the banks. We see Shield Ferns Lastreopsis sp and clumps of Blechnum nudum amongst the rocks. We then return uphill in the cars to the picnic area where we will have lunch. This is a lovely rainforest walk, especially in the cooler weather, and quite easy, so we are hoping to see lots of visitors as well as regular walkers. Don't forget your insect & leech repellent! Snacks and water for the walk, and extra chairs for lunchtime. There are tables and a new toilet at the picnic area. Diana D.
CD - Native Plants & Bushwalks of the Central Coast
Many years ago Alan created a list of plants that the group had identified while on their monthly bushwalks. This list was passed over to Diana & Barry a few years ago and it was then converted into a data base. Over the past 3 years a great many more plants have been added to the list and now 800 plants are included on the data base. Photographs were also collected along the way some taken by Diana & Barry and others taken by some of the keen photographers amongst the group members. From this data base and collection of photos a DVD was produced to run on the coach for the Sydney Tour of the ASGAP Conference last year. This particular tour was subsequently cancelled due to lack of numbers but a seed was planted and the thought of a CD began to grow. After many hours spent at the computer the CD is now complete. It contains over 400 photographs and lists 24 bushwalks in National Parks, State Forests and Reserves of the Central Coast region and each bushwalk has a listing of the plants which may be found along that walk. In some cases maps are included. The disc is available for $15 plus $2.50 postage (within Australia only) The CD can be purchased at any of our monthly meetings.
or if you wish to order
a form is available from this website.
The Committee and members would like to thank Diana and Barry for all the effort and hours spent in producing the CD the profits from the sale of which will benefit the group.
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