UPDATE from Victoria

We will be posting letters to government ministers, officials and bureaucrats so that those of you who are interested in seeing NSF taken seriously by those in command of our country's future, can see our efforts in that pursuit.
We will also post any replies or reactions we get.

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duane
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Re: UPDATE from Victoria

Postby duane » Tue Nov 23, 2010 11:21 am

Sceptic said......
Which proves what exactly?



The good thing about the net is that everyone's an expert. Even those who believe they are well informed.

ghosta
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Re: UPDATE from Victoria

Postby ghosta » Tue Nov 23, 2010 11:56 am

duane wrote:

The good thing about the net is that everyone's an expert. Even those who believe they are well informed.


I think you may misunderstand what the net provides. When someone makes a statement which is not explained in any fashion, readers can quickly ask for more information. If the person who originally made the statement is unable to provide an explanation but resorts to attacking the questioner, then we are able to easily dismiss the original statement as worthless. The net provides a quick and easy way to expose "blowhards".

This is a generalised statement about the net. Readers can make up their own mind whether it has any application to this thread.

Shirley Henderson
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Re: UPDATE from Victoria

Postby Shirley Henderson » Tue Nov 23, 2010 4:49 pm

Hello Sceptic, I love your challenging thinking. I have another question to pose to see what you think. Eucalyptus are far more dominant than ever before. Isnt some of that due to fire and land clearing and doesn't the opportunistic Euclaypt and others that survive fire well become dominant. They seed prolifically and when the seedlings come up in large quantities they grow super fast shading out others and drinking up and storing the moisture giving other plants little chance to compete. If Eucalyptus were not so dense then wouldn't the fire hazard be less of a threat and if the ground was covered with a more diverse variety of plants (other than Eucalytus) again then less of a fire hazard.
Interested in your thoughts and info.

sceptic
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Re: UPDATE from Victoria

Postby sceptic » Tue Nov 23, 2010 9:38 pm

G'day Shirley and thanks. That question opens a whole can of worms which may take me a while to go through but I'll try anyway.

One of the things I've been ranting about for over a decade is the prevalence of PMT amongst both professional and volunteer NRM practitioners and by PMT I mean Plant More Trees. It comes from a very tree centric view of how the environment should look and results in concentration on the overstory rather than the understory where most of the biodiversity and biomass occurs. We see far too many plantings of trees, which at maturity would be 40 to 60 metres height, at one metre spacings with the attitude expressed that "they'll sort themselves out eventually". There are some forests I travel past and have seen for the past 20-30 years which have stagnated and have not "sorted themselves out" (although in some I'm starting to see some dieback occurring) and a lot of our regrowth areas do need thinning to allow full development of both the canopy and understory.

Personally I usually recommend a minimum spacing of 6 metres for tree plantings with shrubs, grasses and groundcovers planted in between and even that is probably too close, 5-10 years in good conditions will mean that that gap is closed up (it does depend on what species and community you're trying to re-establish, open woodland I'd like to go a lot further than that but I have to deal with the PMT issues, rainforest I could go a little closer as rainforest species don't have the naked buds Euc's do and rainforests need around a 70-100% canopy cover, open woodland is 15-30% canopy and forest in between).

Despite me being more a shrub and groundcover person I think Eucs do quite often get quite a bad rap, particularly as far as fires are concerned. Understory vegetation and leaf litter provide the fuel for the initial fire which heats the overstory and volatilises the leaf oils, except under extreme conditions a crown fire won't occur without a hot fire underneath, it is fuels up to around the diameter of your pointer finger from ground level to about a metre in height which provide the most fuel for a fire (this makes fires in heathland and grasslands extremely dangerous - and these areas generally have few or no eucalypts). From 20 odd years of firefighting fires in grass and heathlands scare me much more than fires in Eucalypt forests they tend to burn very hot and very fast with no trees to provide a windbreak and slow the spread (pine forests really scare me as well, there's usually nothing left in them once a fire has been through).

If we got rid of the Eucs would we have less of a fire hazard? Doing that alone the answer is no. If we got rid of all of our fire prone and fire promoting plants (of which there are thousands) would we have less of a fire hazard? Yes there would be less however we would lose an awful lot of what makes this country what it is, we'd lose our koalas, many of our birds, innumerable invertebrates and many, many species of plant.

And yet we would still have fires, as I mentioned previously a Forest Fire Danger Index of 300 means just about everything will burn, some areas of Victoria where houses were lost were in areas where the grasses had been eaten to groundlevel, short of ploughing it fuel levels couldn't have been reduced any further and still the fires burnt (in fact even ploughed areas burnt as the high dry winds picked up small pieces of roots and leaves from the soil).

That'll do for tonight, it's a little disjointed but I'll try to tie it all together in the morning.
The truth is out there.

sceptic
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Re: UPDATE from Victoria

Postby sceptic » Wed Nov 24, 2010 1:49 pm

Ok, now where was I? Yes, there has been human influence on the spread of Eucalypts but climate has played a major role in it as well, here's a bit of an introduction to them. Attributing the ills of the Australian environment and the fire sensitivity of it to one particular plant genus is a fairly simplistic way of looking at things.

There's over 800 species of Eucalypt covering a huge range of habitat from deserts to wetlands to the high alpine areas and while, to the best of my knowledge (or at least the ones I know), they do require bare soil to germinate they do show a great range in their response to fire. The bare soil can be due to floods (as in the case of River Red Gums) or after prolonged drought (as in many of our woodland species) or an openning of the canopy and baring of soil due to storms (as with many alpine species) and yes they do take advantage of the situation after fires (as do a great deal of other native - and other - species). These trees provide habitat for thousands of different species of birds, mammals, reptiles, invertebrates, orchids, fungi etc and do play a part in our climate, water transpired through the leaves rises, cools, condenses and falls as rain and forest areas do encourage rainfall due to their albedo (or surface reflectivity), it's cooler above a forest than a dry grassland so vapour condenses much more easily (and green grassland is more likely to get rain than dry grassland).

I don't know if I've made anything clearer but I think I've shown the complexity of the subject and the whole interconnectivity, I know I've certainly managed to confuse myself.
The truth is out there.

ghosta
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Re: UPDATE from Victoria

Postby ghosta » Thu Nov 25, 2010 8:36 am

Sceptic I think you have made a pretty fair fist of your explanation as to the dominance of eucalypts in Australia.

I dont agree with you that we nee to be concerned by the move to plant more trees. Revegaetation of sites has been an important step forward in the Australian landscape, and if you look at many more recent projects they now include more than just Eucalypts and often include understrey vegetation. Of course Im not talking about "commercial" plantations, rather what has been done by Landcare groups, farmers, civic authorities etc.

I do hope there is more thought in future put into the selection of species planted on the urban interface and around buildings for fire reasons.

I would also like to see some research done to see if vegetation plantings on farms have any significant impact on the fertility of adjacent pasture land....both natives and introduced species. Ive not directly heard of an instance where a farmer was able to reduce or eliminate the use of fertilisers adjoining shelterbelts or forested areas and still maintain productivity, but there may be apropriate species for given soil and climatic conditions where there is an added significant increase in fertility to adjacent pasture.

sceptic
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Re: UPDATE from Victoria

Postby sceptic » Fri Nov 26, 2010 7:57 am

I don't object to planting trees, I think it's a great thing but we do pay too much attention to trees and not enough to understory species and the constant message put out by Landcare, Planet Ark etc is all about trees we need to think more about what we plant and how, yes we need trees but we also need shrubs, herbs, grasses (and even fungi but I'll leave that one for another time). I agree some Landcare* and other groups are including more understory species, unfortunatelly not enough and often professionals in the industry forget about the understory and often plant trees too closely together (a recent example I can think of was a professional tree planting crew planting river red gums a metre apart).

*A landcare group I was involved with for 10 years made a decision to plant only understory species in an area of severely dieback affected Spotted Gum, with quite wide spacing and leaving areas of grasses, the are now is recognised by the local council as a major asset, the dieback has been arrested, the understory now has second and third generation (and more) plants and the wildlife is loving it. It helped that the group had quite a few Environmental Scientists, Bush Regenerators, Landscape Architects, Nurserymen (and women) as well as a lot of people passionate about saving the Australian environment.

I don't know of any research into the fertility effects of shelterbelts, though I suspect fertility wise it could be a two edged sword, trees do drop a lot of leaves which can contribute to soil organic matter however this can have the (temporary) effect of causing nitrogen drawdown whereby microorganisms take nitrogen out of the soil in order to decompose organic matter, planting of Wattles and other Fabaceaes would probably combat this as they fix nitrogen from the atmosphere (Casuarinas fix nitrogen as well but utilising a different method {which I can't remember at the moment}).

There has however been work into the effects of shelterbelts on crop yield, essentially closer to the shelterbelt the yield is down (due to competition for nutrients and water) however as you get away from the belt yield goes up to higher than it would have been without the belt, dropping off back to normal yield as it gets further away. The reduction in windspeed due to the shelterbelt leads to lower evaporative losses, hence more moisture can be used for growth. The other benefit of shelter belts is that they provide habitat for predators and pollinators, reducing the amount of crop eaten by insects and increasing pollination.
The truth is out there.

sceptic
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Re: UPDATE from Victoria

Postby sceptic » Fri Nov 26, 2010 8:28 pm

Correction, there is apparently some recent research into trees and soil fertility, I'll track it down next week.
The truth is out there.

sceptic
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Re: UPDATE from Victoria

Postby sceptic » Wed Dec 01, 2010 11:46 am

aah here we go, from "All the Dirt",

All the dirt is produced by Industry and Investment NSW (formerly NSW DPI) and published by the NRCMA. Email to subscribe, unsubscribe, contribute or comment on this newsletter:
allthedirt.newsletter@industry.nsw.gov.au

Paddock trees help soil fertility
As well as offering shade and shelter for livestock scattered paddock trees are good for soil health and pasture growth. Phoebe Barnes at the University of New England has been studying how paddock trees affect soil fertility both under the canopy and at distance from the tree. She found that paddock trees improved a range of soil nutrients both under and away from the tree.
In the paddocks the nutrients phosphorus, nitrogen and sulphur, as well as soil carbon were highest under the tree, and decreased moving away from the tree trunk. The higher nutrient levels were in the surface soil, suggesting a top down effect from leaf litter and possibly increased concentrations of animal manures. Soil moisture showed minimal additional extraction of water by the trees in the 0 – 30 cm zone suggesting little competition with pasture species.
The main message is that the effect from a single tree extends beyond its immediate canopy area, extending up to 16 m from the tree trunk for a mature tree. The results from this study suggest that a tree density of up to 11 large (with a canopy diameter of 13.5 m) well spaced trees per hectare could benefit soils and pasture growth by increasing surface soil pH by 0.5 units, soil carbon by up to 80%, available phosphorus by 70% and nitrogen by 20 % compared to a cleared paddock.
The truth is out there.

duane
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Re: UPDATE from Victoria

Postby duane » Thu Dec 02, 2010 7:56 pm

That's a good find sceptic.

Here's another....there are also some good diagrams and general information on this site http://www.seafriends.org.nz/enviro/soil/ecology.htm about the role of both trees and animals in the building of natural fertility.

sceptic
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Re: UPDATE from Victoria

Postby sceptic » Thu Dec 02, 2010 9:07 pm

There's a lovely story in David Suzuki's book "Good News for a change" a researcher was studying the nitrogen cycle in Canadian forests and gave a talk to a gathering of Inuit people (or was it First Natons?), who apparently listened in fascination as he described the role of the salmon, being caught and eaten by bears with the bears doing as bears do and crapping in the woods fertilising the trees and keeping the whole system healthy. Despite the hard science this was well received and tied in wonderfully with the Indigenous legends, stories and ecological knowledge and explained why daming the river often led to disease in forests above the dams. I've often wondered what impact has been had by humans no longer crapping in the woods in this, and other, countries (the role of nutrients in Australian ecosystems is a whole new discussion in itself, it's not always a good thing).
The truth is out there.

ghosta
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Re: UPDATE from Victoria

Postby ghosta » Fri Dec 03, 2010 10:15 am

Thanks for your posting sceptic. I think Ill leave your "human" post alone.

The study you posted an extract from raises more questions for me than it answers. Thats the nature of research, it allows others to build on the findings.
some things that come to mind are-
1) Is the fertility around trees primarily a result of transfer of fertility from the open field to under the trees?
2) Is the increase in fertility actually significant from a farming perspective? If low levels of say phosposus were originally present a 70% increase may mean not be actually a significant change.
I wont continue on in any depth as we have already taken this thread well off topic.

Shirley Henderson
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Re: UPDATE from Victoria

Postby Shirley Henderson » Tue Dec 07, 2010 5:28 pm

HI again, Thanks for all the information. Much more to mull over. I am with the planting of diverse plants, trees, shrubs, groundcovers and ensuring a wide mix of species. I believe the reason for planting so many trees close together is the low survival rate, sometimes as low as 15% (that is considered good by some) . Long stem planting has a proven success of 70% so under those circumstances they probably would not plant them so close together. Yes, I think some Eucalyptus are great but we tend to overdo that. If ideas are changing there I think I would support it especially where we humans live. We do want a healthy functioning landscape and I appreciate Peter Andrews research and work creating the healthy floodplain and functioning system he has restored. Also Mulloon looks fantastic as a building system that is functioning well. I do not own farmland myself so am probably considered a towny but I live and breath many days in the bush. I work in the bush, live amongst bushland and spend as much time amongst it as I can, working, learning, observing, and building my knowledge on natural functioning systems. I live around farmland and watch what is happening around me. I believe there is a lot to learn just by leaving things alone sometimes and seeing what happens. So thanks guys and as always I will be following the threads here for interesting topics, information and listening to the experiences of others. Occasionally I will throw in something interesting too.
I would love to hear from people in Victoria as to what there opinions are about the recovery from the fires and if there are any changes actually happening. I bet there is a lot of talking going on and not much change due to disagreements and lack of understanding. I heard there was a lot of weed control going on but do not agree that is a solution. At least they hold water, assist the small water cycle, provide habit, shelter, food sources, moderate temperature and provide groundcover etc etc etc........ Anyone know?
Shirley

duane
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Re: UPDATE from Victoria

Postby duane » Thu Dec 09, 2010 11:53 am

Hi Shirley

Appreciate you bringing this thread back into line.

The Victorians have been very proactive.

They now have their own website http://www.nsfvictoria.com/

I have also sent your post to them inviting a reply on this thread to this forum.

I am hopeful, someone will reply to your questions.

ghosta
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Re: UPDATE from Victoria

Postby ghosta » Thu Dec 09, 2010 3:11 pm

Shirley Henderson wrote:. I heard there was a lot of weed control going on but do not agree that is a solution. At least they hold water, assist the small water cycle, provide habit, shelter, food sources, moderate temperature and provide groundcover etc etc etc........ Anyone know?
Shirley


If you follow this link you will have some indication as to the priority weed control is given following the bushfires.

http://www.google.com.au/url?sa=t&sourc ... oA&cad=rja

Whilst weeds can provide the benefits you outline in certain circumstances, they are weeds after all.

What is a weed- (from Wikopedia) "A weed in a general sense is a plant that is considered by the user of the term to be a nuisance, and normally applied to unwanted plants in human-made settings such as gardens, lawns or agricultural areas, but also in parks, woods and other natural areas. ..."

Weeds grow profusely after a fire as you are no doubt aware, and money spent early on can mean the job of eliminating them is done at less cost. Lets not confuse weeds generally with the use of weeds in NSF where a deliberate decision is made to use weeds to serve a specifuc purpose.

Peter Andrews can find a use for most weeds in HIS circumstances, but that does not mean everyone else can or should. What is more important in the farming situation is the principles behind their use ie a normally absent species of plant is used to hold soil, prevent evapouration, build up fertility, soil structure etc etc. There may be more suitable species to do this, other than just what weeds the wind blows in, and i suspect this is an area that needs a lot more research. If you are a wool farmer, for example, then some types of thistle will substntially downgrade the value of a wool clip through contamination of the wool, yet for a horse breeder may present no problem at all.

A native forest will normally have native plants which respond to a fire and are quickly replaced by more advanced vegetation as time passes. Non native weeds may even disrupt the normal pattern of sucession.


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