Saving Gwondanaland

Welcome to Spiderland

2012-01-01T18:27:00.000+11:00

The dry summer heat has started in earnest yesterday and today saw a cloud of insects congregating in my little strip of Gondwanaland enjoying the humid micro climate. Then today with hours the open spaces where criss crossed with new spider webs and judging by the number or holes they had already done battle and eaten a number of those large buzzing blow flys.

BTW the Gondwanaland garden is on the south side of my house and it definitely cools the entrance and lower floor. Natural Air conditioning, at least while this ferny glade restrains some of its natural humidity.

returning to gwondanaland

2011-07-19T17:19:00.003+10:00

returning to gwondanaland
Originally uploaded by imageo.

It has been a while since I have blogged about my Cretaceous garden, because it has been left to solider on by itself. A classic case of gardening by neglect and in fact it has looked after itself rather well, albeit becoming a touch overgrown.

Admittedly the weather has been very kind, lots of rain, but i am impressed with how fast the ferns have recovered from the drought conditions of the past few years.

The first art work arrives

2011-05-05T18:29:00.001+10:00

Not many gardens boost works of art these days, but Gondwanaland has a new wall hanging. It’s one of the rock panels from my “Retracing Darwin” exhibition fitted out as the new home for an stag horn fern [Platycerium]. The fern is “growing” over my representation of the geological layers representing the Permian mass extinction event. A somewhat poignant reminder of the larger cycles in nature.

I think it looks perfectly at home.

Wet, Wet, Wet

2011-02-06T19:54:00.000+11:00

Well the rains have come (at last) and Gwondanaland is more like a river than a garden. Also some water restriction have been lifted but now no one needs to water their garden.
It is amazing how the ferns have come to life. Everything is gushingly green again

Travelling

2010-05-07T12:13:00.002+10:00

My Wollemi pine, is having a vacation. It is part of my Retracing Darwin exhibition down at the Gecko Gallery Studio at Fish creek, That’s the pine in a pot down in the corner amongst the things Charles Darwin didn’t see or describe, when he travelled from Sydney to Bathurst in 1836. From Govert’s Leap Darwin did look out down into the Wollemi national Park. Instead he just complained -

16th. Everywhere we have an open woodland, the ground being partially covered with a most thin pasture. The trees nearly all belong to one family;1 & have the surface of their leaves placed in a vertical instead of as in Europe a nearly horizontal position; This fact & their scantiness makes the woods light & shadowless; although under the scorching sun of the summer this is a loss of comfort, it is of importance to the farmer, as it allows grass to grow where it otherwise could not. — …. It is singular that the bark of some kinds annually falls, or hangs dead in long shreds, which swing about with the wind; & hence the woods appear desolate & untidy. — Nowhere is there an appearance of verdure or fertility, but rather that of arid sterility: — I cannot imagine a more complete contrast

In good health

2008-12-03T16:54:00.001+11:00

My wollemi pine gets its anuual-ish repoting. Compared with other pines here in victoria it is looking healthy with some new growth visiable (probably related to the fact that i still "hand" water it by placing it in a bucket of shower water regularly). However it is starting to look just a little spindly and I am wondering if it is a good idea to prune and if so when? Checking the wollemi website suggests shaping is a good idea and anytime of the year, but sterile secateurs!

Position, Position, Position

2008-07-28T21:09:00.000+10:00

Rain gauges, like most meteorological instruments, should be placed far enough away from structures and trees to ensure that any effects caused are minimised. The Nylex Rain Gauge 1000 instruction leaflet suggest the gauge should be located twice as far away as the height of nearby buildings and trees (ie if your house is approx. 3m high then the gauge should be 6m away!) I have two of these rain gauges (normally at different locations) but I have already noted that then can give different readings with only small separation. The main culprit is wind. nearby obstacles can cause shadows and eddies and if the gauges is too exposed eddies in strong winds can carry away up to 20% of the rain. Finding a good site is a standard suburban block can be a challenge and using two gauges (these can be homemade) at various locations is a good way to select best location to permanently mount your rain gauge.
Swalim (the Somalia Water & Land information Management) project has put their comprehensive Rainfall Observers Manual on the net.
The rain gauges that come in most weather station kits are based on tipping buckets. These are generally not as accurate at the conventional graduated cylindrical collectors, for a couple of reasons. A certain amount of rain is needed to tip the buckets and the rain event may finish before the bucket is tipped, where the rainfall is infrequent and low this can be an issue. Also the tripping mechanism may have considerable tolerance (most are made of molded plastic) and it may be wise to "calibrate" the readings against a convention gauge (using a few decent rain events of perhaps 2mm of more)

Handling the pressure

2008-07-27T15:12:00.000+10:00

Aneroid Barometers are the most common way to measure atmospheric pressure. But the first barometers use columns of displaced mercury to measure pressure, which is why pressure was originally measured as inches of Mercury (InHg) or millimetres of Mercury (mmHg). At the beginning of the 1900s the millibar (and bar) was introduced as the international measure of atmospheric pressure. Today most instruments give measurements in hectopascals.
The earth atmosphere gets thinner with height, because of the weight of air above it is less. Infact an aneroid barometer can be used to measure altitude. Air pressure gets roughly 1 hectopascal (Hpa) lower for each 10 metres of ascent. To test this I took my reference barometer (a decorative one rather than a highly precise instrument) for a drive up to Olinda in the Dandenong ranges. I got a rough reading from Google Earth that I started at 74m and reached 577m elevation at Olinda (this is most probably several 10s of metres out by the way but I was only interested in relative height difference and have assumed that both estimates are similarly out). The initial reading of the barometer was 1010 HPa and was 960 Hpa after I let it rest for a while on an old tree log at Olinda. An inquisitive Kookaburra took an interest (presumably seeing if it was edible). So there was approx. 500m difference in elevation and the air pressure dropped 50 Hpa. My old barometer seems ok, and a worthy calibration companion for my new weather station.
Most published weather charts show the air pressure at sea level (MSLP, Mean Sea level Pressure) and so it has become a convention to set barometers used in weather prediction to a "relative" pressure at sea level. Normally you can obtain this by finding details of a nearby government weather observatory (BOM Bureau of Meteorology in Australia) and adopting that pressure as your reference. Modern aneroid barometer often have a small adjustments on the back to do this. Digital barometers and weather station usually have a set/calibrate procedure, to change the displayed reading.

Weather Station Gwondana

2008-07-26T00:57:00.001+10:00

Rather than just think conspiracy theories about the dams and rainfall I figure it might be more constructive to start observing the weather events myself. Surprising it is possible for anyone (with an interest in weather) to do some simple observations themselves and become proficient in local weather forecasting themselves (at least that what the Discover Nature in the Weather websites say).

All that is required is some simples measuring apparatus, and most of that can be homemade if you want. The key items are -

Whilst I have "analogue" version of all these apparatus and know how to use them I was inspired to go "digital" and get a wireless weather station that has an "indoor" LCD control panel, that receives data wirelessly from external mounted measurement devices. Its not a model that can be connected directly to a computer (and then the net) that would make this extravagance way too expensive.

So my weather station is in (just above my cretaceous garden, and over the next few weeks I will be calibrating things. After that you can expect some weather observations to start appearing in here.

I am not normally a fan of conspiracy theories

2008-07-13T20:30:00.001+10:00

Looking at the published levels of stored waters in our dams in Melbourne is a little depressing, it is only just at 30% of capacity at a time when there have been some decent rain events (I have rain gauges and tanks), so is there a conspiracy are we being told the truth?

I started looking to find an independent way to verify this (ie not just looking at one source of data). If you look at the Melbourne Water website they have a graph that shows the inflows into the dams over 2007 are roughly at the average for the last 10 years but that they were only half this in 2006. I then look at the Bureau of Meteorology statistics (see graph below), it is clear that rainfall is below average (between half and three quarters of this part of Australia. So superficially thing check out.

However at a more detailed level things don't seem to match up. We should have had lower levels in the dams last year, but it seems a lot of water was "taken" from the Thompson scheme. Then A lot of water was lost in some flooding in Gippsland ...etc ... etc the plot thickens, but not quite to a conspiracy level but I do think this has the hallmark of politicians with their hands on what history is being recorded (sorry disclosed).

But where & how to build an independent view?

first blushes of spring

2008-07-09T18:18:00.002+10:00

We have just had the first blast of really cold winter weather, even snow, and already the wattles and blossum trees are showing the first blooms. Normally this is an indicator that spring is on its way. So are we in for the shortes winter or are the plants wrong? The observation of naturallt reoccuring events is know as phenology and was the passion of some of great naturalist last century like Thoreau and Darwin. I wonder how many sign from nature we miss every day in our busy lives?

Other Gwondanaland Plantings

2007-09-17T22:58:00.001+10:00

I do not want to give you the impression I have the sole little piece of gwondanaland struggling to survive. A lot of direct descendants of the original Cretaceous forest still struggle on today out in wild. Some are ideally acclimatized for the harsh climates of southern Africa and Australia. Others are tropical forest specialists. Some are being pampered in special collections, like these cycads in Adelaide's Botanical Gardens.

The green drought!

2007-09-09T21:12:00.001+10:00

It has been a long time between post. I seemed that the rain had come and things where returning to their normal seasonal cycle.

However I have just noticed that the new fern was looking decidedly dry. Maybe it was true, the myth of a green drought was coming true. I firmly believe the culprit was actually a few days of unseasonal dry north winds, but I am returning to the shower bucket method and watering the head of the stem as new shoots emerge just to be on the safe side.

The palm "terrace" takes shape

2007-04-12T18:02:00.000+10:00

The new fern has prompted me to remove the remaining bamboo (a hard task by the way) and start the basis for the palms end of my cretaceous garden. I know "Palm Terrace" is a lofty title but it is a fraction elavated. I plan to leave the center hollow so I can rotate potted palms from indoors. The soil is hopeless clay but in the process of digging out the babmoob runns it has had a good digging over. I plan just to add about 30cm of leaf litter rather than a top soil to gove it a rainforest floor feel. The fern looks quiet happy after its transplant, despite the continued warm (and dry weather)

something new

2007-04-07T22:31:00.000+10:00

This is the first time I have noticed a spiders web in my cretaceous garden. It might indicate that the garden is drying out, normally I associate spider webs with dry, very low humidity, places. Whilst i have seen plenty of spiders around, red backs, white tails, and huntsman, but i suspect this is an orb spider web (the nicely circular section on the center is very characteristic). You never know it may well be a close relative of the spiders in space that perished when the columbia came apart on renetry. Those golden orb spider came from around this way.

Looking around the web, internet that is, I still can't find any evidence to support my suspicion that spiders webs mean the garden is drying out, but here is great page a spider myths

saving a tree fern

2007-04-05T20:31:00.000+10:00

The tree ferns of melbourne are having a hard time, even my own ones. They seem to have been dropping their outer fronds, dry and brown at a great rate. I suspect it is just a sign of drought stress, a lot consider that they are dying. Anyway to cut a long story short I have me offered a couple if i think I can save them.

Well I may as well have a go, my first patient is a very thin fern and I can not figure out exactly which species it is, my best guess is Dicksonia fibrosa. So rather that just do the old saw it off and stick it back in the ground, whichwork well enough for Dicksonia antarctica, I decided to get a significant part of the root mat, which were only growing across the surface.

I also trimmed off all the fronds other that the new sprouts. With a little close supervision to make sure the roots don't dry out I expect it will thrive in my little bit of gwondanaland.

The final problem remains where to plant it?

Something for April Fool's Day

2007-04-01T10:24:00.000+10:00

Its official Melbourne's water storages are currently 32.1% full (as at 1/4/2007). Despite the rain the overall storage is still falling. Some dams are rising by other failing a lot. Should this be a problem? The common explanation seems to be that the soil is taking up all the moisture and keeping run-off into the dams minimum. Another explaination is water may to be being shunted around.

The aprils fool day message bit is that this should have triggered level4 restrictions. However the Victorian government, or more specifically those politicians based in Melbourne,has gone a bot weak at the knees and changed the rules. So now we are have a claytons change to the rules when a real change to the rules could have had a bit of a voter backlash. So now we have water restriction level 3a.

Happy Plants

2007-03-31T16:46:00.001+10:00

growth collage
Originally uploaded by imageo.

Yesterday's rain has given way to sunshine and a glorious march day, perfect to take some photos for the photofriday challenge growth. The plants just seem to be happy :)

rain

2007-03-30T15:42:00.000+10:00

Well decent rain is falling, and we may even get close to our normal march average. With the long term predictions still suggestion better than average rains through autum. If you are interested the Australian Bureau of Meterology has a great area on their website to graph and compare a number of key climate measures.

sorry for the hiatus

2007-03-30T10:52:00.000+10:00

I've been away and back and away a lot, so my humble cretaceous garden has had to fend for itself. It has done so admirably, compared with other more conventional plantings elsewhere in my garden. So I think there may be a myth, ormoral here, perhaps cretaceous plants thrive best by neglect! (and tropical weather, even without the rain).

What the?

2007-02-19T19:54:00.000+11:00

The bamboo, that I still intend to remove, is one plant flourishing, But why the heck is this new miniature growth appearing on most spikes. Is it the mythical 50, or was that 500 year flowering. The myth says all the bamboo dies (now that would be a good thing) after that gregarious flowering event but famine, dark despair and untold hardship descends on the land.

the rule of 10

2007-02-18T09:58:00.000+11:00

I've been away and my garden missed any watering for almost two weeks during hot dry weather, with the remote possibly of a local thunderstorm/downpour in there maybe. Things were looking wilted but survived, infact the cretaceous part has faired better than most other parts of the garden (most probably because it is protected from the scorching north winds). One water and things seem to have sprung back to life.

So "How long to water?" is probably the big question around here at the momement. My mother's suggestion is possibly the best I have heard

Count to ten (1..2..3..4..5..6..7..8..9..10) slowly as you water important shrubs
...my mum

How much water the plants get depends mainly on your water pressure and which nozzle setting you have on your triger hose (under current water restrictions you can only water, at the designated times, using a hose fitted with a trigger nozzle, which instantly cuts off the water when you release it). However it is easy to work out the flow, just place the hose into a standard plastic bucket (most of which have volume marks on the side) count to 10 and see how much water is there. With a bit of calibration you might be happier count to 5,7 or even 15).

How much water your garden needs, is a more complex issue and is sure to be the topic of posts to come.

The bucket brigade, a month on.

2007-02-06T09:39:00.000+11:00

Melbournians, including me, have embraced using plastic buckets as a really easy way to save water (eg. first flow in the shower). In fact their has been a massive 24% reduction in water usage for january 2007 (compared with the same time last year) in a year when January has been significnatly hotter and drier than average. So water restrictions are working and most people are acting responsibly. We even have a website to monitor weekly water usage now.

Well done folks.

Drip Watering #4

2007-02-05T09:18:00.000+11:00

The Melbourne City council have come up with a great way to water their significant trees. All around the center of Melbourne at the moment you will see the red and white traffic barriers babysitting a big tree. These barriers are designed to be filled with water to make them heavy, in their normal traffic`hjazard management duties, but with the simple addition of a drip hose they can become a personalised tree watering system that the council can refill with recycled water periodically.

Nocturnal visitors

2007-02-02T21:29:00.000+11:00

This guy, a small bushtail possum Trichosurus vulpecula, is not such a welcome quest. His relatives devastate fruit frees and prize plants around here this time of year and seem to be flourishing in tree lined street of Melbourne. Whilst they are officially protected in Victoria, most locals consider them pests. Despite looking cuddly and docile these small marsupials have sharp teeth and claws as many dogs and cats soon find out.

This is the species of possum that has caused such environmental destruction, when they were introduced to New Zealand.

my other (token) conifer

2007-02-02T11:07:00.000+11:00

At the moment they only other conifer (other than the wollemi pine),is a very low growing juniper. It was planted long ago, vaguely I remember it having a name like carpet juniper, and it looks a little like a Juniperus squamata but thats supposed to be fast growing and this one is definitely not that!

I did have two other conifers, pencil pines, but they were growing so fast and tall I had to move them well away from the house. They were definitely unsuited to my restricted space. Now I just have to dream of getting a more slow growing King Billy, Celery top or Huan Pine to replace them.

An interesting (re)discovery

2007-02-01T15:18:00.000+11:00

Today I came across some old sketches of my original ideas for the cretaceous garden. The first was perhaps a little ambitious, with a water feature and mini pier from the carport. However on the back of this sketch was an interesting hand written list-

suitable plants with cretaceous ancestors

ferns
moss
cycads
laurel (eg sassafras)
cypress (low growing)
deciduous beech
ginkgo
bamboo ??

The fact that I had included bamboo suggest that I had not researched this list well, if at all. Grasses, of which bamboo is one, didn't really evolve until until after the cretaceous (but more about bamboo later) I suspect it is on the list because it was already there in the garden.

I also has a second list of look-alike cretaceous plants

broad leaf cover (eg aspidistra)
pin cushion plant

Looking back that was a pretty good list to start, and matches what has flourished, I'm giving myself 7 out of 10 for plant selection (now is that a B minus or a C plus on a standardized marking system?)

My second design is much closer to what I have created it has a dry creek bed of rocks instead of a pond. I left out the stepping stone and have a mini island instead.

You might like to see what the area looked like before it became cretaceous.

what's happening to ENSO?

2007-01-31T21:17:00.000+11:00

Like many weather watchers the Australian Bureau of Meterology has its own El Niño watch page on their website, and today it has some good news

"Summary: El Niño continues to weaken

... it bodes well for a switch towards average or wetter than average conditions across eastern Australia sometime in the late summer or autumn."

CURRENT STATUS as at 31st January 2007

In simple terms that means more rain and maybe even the end to the current drought conditions and it will start happening soon. Assuming it does I will confidently predict now that this will re-ignite a lot of discussion about whether the drought conditions in south-eastern Australia are part of a normal el-nino cycle or that they are evidence of mankind induced climate change.

If you want to monitor the changes in el niño, also known as the southern oscillation (or ENSO), the Noaa/TAO website is a great place to start.

New growth update

2007-01-31T14:00:00.000+11:00

The new growth at the top of my wollemi pine are developing fast into a new series of branches. I'm amazed how quickly they are developing and the muliple branching. Might be time to repot the plant, or maybe I should wait till after the next hot spell.

meet the cycads

2007-01-30T14:39:00.000+11:00

Cycads (pronouces sigh-kads) are an order of plants that flourished during the Mesozoic Era. They have large pinnately compound leaves (fronds) that superficially resemble palms and some ferns. However these plants have a markedly different strategy for reproduction, since they developed before insects had evolved on land. They are dioecious, which means there are seperate male and female plant, and have cones rather than flowers.

Cycads are very common in the Australian fossil record They are generally very hardy plants and are still growing in many parts of the world. Most widely in South Africa, South America, the Pacific and Australia (as a relict of their Gwondanaland floral heritage). They are widely believed to have been a significant food source for dinosaurs. The seeds of many cycads are poisonous, containg BMMA, a neurotoxin which results from the cycad's roots close relationship with blue green algae that also helps these plants fixed nitrogen into the soil. In the pioneering days of european settlement in Australia, cycads where "harvested" as a rich source of starch, not for eating but as a laundring aid.

I have several sago palms, cycas revoluta, a japanese variety, which is probably the most popular cycad for cultivation. They where starting to look very unhealthy in the heat, the frond turning yellow and dropping down. Then just as I was worrying, two of the larger plants sent up new fronds. I am not sure if it was the heat, or the smoke hazy that triggered this change, I remember hearing that cycads are a type of plant that flourish after a fire

the bird nest fern

2007-01-25T23:16:00.000+11:00

The birds nest fern,Asplenium australasicum, is a epihyte fern which is common in the tropical rainforests of northern australia and nearby pacific islands. It has long simple radianting fronds that are an attractive light green. Like the soft tree fern its inverted umbrella shape of fronds helps collect and channelwater and leaf matter down onto its growing center.

Of all the plants in my garden it is this fern that likes the highest humidty. I expect this to be the best indicator plant of creataceous-like condition in my garden. However since it doesn't have a true ground penetrating root system it does not really give me a representative view of the saturation/driness of the soil.

more yellow spots

2007-01-23T17:28:00.000+11:00

Just noticed more yellow spotting, this time on a small cycad, is this a sign of drought stress, air pollution or another problem from the hail at christmas. For now I'll assume it is hail damage and the plant will recover.

Where did the cretaceous weather come from?

2007-01-21T15:15:00.000+11:00

The anwser is simple it came dowm from the tropics. Looking at the lastest satellite image, which I got from the Bureau of Meterology's satellite page. You can see the big band of cloud coming down the east coast of Australia. A tropical Low (low pressure area) in Northern Australia had connected with low coming acrosss the Great Australian Bight and it just sucked all the hot moist air south (where it is needed)

Where did the water go?

2007-01-21T14:03:00.000+11:00

The water levels of Melbourne's dams are now published daily, and a surprising number of people are well informed on the levels. Today "The Sunday Age" had a story about the bit dry (it has actually rained for two days now) and mentioned that the dam levels fell 0.1%, in a sidebar, strangely the article only indicated 8mm of rain in the past 24 hours and the rainfall section back a bit only showed 1.5mm. I can tell you it rained more than that. Checking on the net I could see that the average around melbourne was 24mm and some place over 40mm in some places (mainly the areas were our water catchments and dams are). This which is closer to what I expected.

So what is going on here. Well I found one likely cause, the news paper story is probably not basing its discussion on up to date data. It appears to be based on Melbourne Water's website (which at the time of writing had not been updated for the recent rains.)

This melbourne water conserve water website is interesting, it gives all the dam levels and also mention that melbournes consupmtion (on average, and that means without water restrictions is 500 giga litres, which is 500,000 megalitres). The full capacity of our dams from this source is 1,773,000 megalitres which is about three and a half years supply. We are now down to 66,577 megalitres and that thens leave close enough to 1.32 years of unrestricted use. Sorry haven't managed to track down the about of water that is expected to be saved by the restrictions.

The inaccuracy of the newspaper report asided, does all the panic about water and water restrictions really seem like we are despeate and about to run out of water? Over a years worth does seem ok to me when much of northern victorian has virtually none left, but to me it is even harded to justify expensive TV adds to dob in water wasters.

Or is the urgency perhaps more to do with political spin!

Some excitement

2007-01-20T15:05:00.000+11:00

The humid weather, and being given a spell out in the rain, has prompted a littel growth spurt on my wollemi pine. At this stage I'm not sure if its buds for new braches or perhaps some cones developing. I'll keep you posted

soaking rains, at last

2007-01-19T11:01:00.000+11:00

Well overnight and this morning we have had some decent soaking rain. Perhaps not enough to fill the dams or put out the bushfires, but the plants certainly liked it (and so have the birds). It is still hot and humid, I would imagine this is perfect cretaceous weather.

cast in iron

2007-01-18T11:27:00.000+11:00

The Aspidistra (Aspidistra elatior) better know as the cast iron plant was a very popular indoor foliage plant in the Victorian era. To the best of my knowledge it is not related to any Cretaceous plant species, it just looks a lot like some of them. It also has the massive advantage that it is thriving in the dry shady areas under the tree ferns.

They are angiosperms (flowering plants), but I haven't seen any flowers, apparently they occur at soil level and are only pollinated by terrestrial Amphipods little shrimp like creatures, (such as sand fleas, and other little bitty varmites). The angiosperms developed late in the jurrasic and spread extensively in the late cretaceous, particularly in the northern continent of laurasia.

Grey Water : Marque II

2007-01-17T14:13:00.000+11:00

Whilst at the hardware I bought 15meters of 13mm black poly tubing (for my drip irrigation work) so I thought I'd try out syphoning out the gray water. Our washed empties into a special drain on the laundry sink, so it is easy to lift the washing machine discharge tube out of its drain and direct the discard into the sink. The theory was that I could them syphon the water from there.

BUT there were problems. Firstly it is important that the water level does not get higher that the washing machine's discard tube, or the water pumped out will backwash syhpon back into the machine (I learnt this the hard way). Second starting the syphon is not so easy with the 13mm poly pipe. Using the well tried method, of making three or so loops and letting all the air bubbles out then clamping you thumb over the end and lift the loops out and then let off your thumb, was not so easy with the tubing which wanted to kink and fold rather make the tight loops I needed to get into the sink. The tubing is light and wants to float to the surface, and loose suction, so I need a brick to hold it down.

With patience I got the syphon going and it worked well. Still it was a lot or mucking around you probably would not want to have to do that routinely.

Waiting for the rain

2007-01-17T11:11:00.000+11:00

So the heat (over 40 C) continues, the serious bushfires continue and the weather bureau is forecasting "chance" of rain and "risk" of thunderstorms. I think that is just bureau spin for a few drops of rain, which unfortunately evaporates soon after landing. The drought drags on.

Without doubt the best way to deep water your garden is via natural heavy rain. However the continued dry conditions can cause soils to become hydrophobic (literally it means afraid of the water) which in physical terms it means that the soil gets a skin that repels water. How soils are affected depends on the soil type. In Melbourne the most sandy soils will quite quickly become hydrophobic, the surface affected with waxes from plants, air fall of hydrocarbons and oily polutants and possibly some natural near surface fungal and baterial actions. Melbourne more clay soils (>30% clay) areas will also be affect but only after the clay has started to dry out. First it becomes very hard, and then surface with start get powdery and large shrinkage cracks will open up. This occurs because the clays are loosing their formation water (water that makes up part of clays crystal structure). The fine powder particles of this dehydrated clay are then on the look out for water and will stick to water droplets rather than staying attached to other clay particles. The clay coated droplets soon coagulate and form a mat that forces any further water to run-off.(This drying of clays has the potentially to damage structures, like your house, via subsidence but this will need to be a separate post)

The best way to fix this in the long term is to add lots of organic matter to the soil to change its structure, and add a surface mulch.(when mulches are too thick and allowed to dry out they can apparently themselves become hydrophobic)

In the short term there is a group of materials called Surfactants (or wetting agents). They work by reducing surface tension of water, and are generally complex organic compounds which have one end which is water loving (hydrophilic) and the other water averse(hydrophobic), they work by acting as a joining agent. Soap and detergents are good surfactants, so using soapy grey water on areas that seem to be becoming hydrophobic has some merit as a good way to pre-wet the surface.(but the affect may only last a few hours).

Introducing the plants

2007-01-16T14:50:00.000+11:00

How rude of me I have been rambling on mainly about watering and I forgot to introduce you to some of the important plants in my 100 million year old garden. The plants themselves are of course not that old, most are less than 10 years old. They are just the same or very similar species to those that existed back in cretaceous times.

Having a look at my plants I see that my Ginkgo Bilboa (Maiden Hair tree) has some spotting on the leaves. Not sure if this is drought stress or the result of hail at christmas. You can see a younger and happier leaf, on the same tree, in my photo blog, wandering in the light.

The gingko is not only a fascinating plant, it is the source of a powerful phytochemicals (commercially produced GBE or Ginkgo Bilboa Extract, is normally standardized to 24% ginkgo flavone glycosides and 6% terpene lactones) that has many claiming it as a wonder drug but it cannot be safely mixed with a number of common prescription medicines, including asprin. You can also dry the leaves yourself and make a great "pick me up" tea. Another amazing fact I found out about gingko is there are four special gingko trees that survived the 1945 atomic bomb at Hiroshima in Japan, and are still alive today.

Stay tune because I'll write a lot about my gingko

Deep Watering : Method #3

2007-01-15T17:05:00.000+11:00

Another good way to water deep and save water is to use a dripper system, and these are allowed under level 3 water restrictions. The best ones are pressurized and have the special dripper buried deep in the soil (20-30cm). They really require professional installation, and are therefore expensive. Right now in Melbourne there is also apparently a long waiting queue to get then installed.

The question I am interested in for now is is there a simple alternative (that works at low/normal pressure). Better still is there a way that I can just replace th heads on my existing "black pipe" sprinkler system. Sounds like a good excuse to visit Bunnings (a big hardware, home improvement and just about everything chain). Well the good news is there are several ways to do this, the bad news (for me) was most where sold out, only the most expensive fittings were left. So I ended up getting buying from the pope range rather than the nylex gardena range (which my system was mainly built from). I also got some repair plugs to temporarily seal some of the riser locations (I didn't want to remove them). Using the variable tricklers (pope Veri-Flow) has has the advantage that I can adjust the flow if individual. Now all I have to do is wait till my watering night, when I can test it out.

Deep Watering : Method #2

2007-01-14T19:28:00.000+11:00

Our local Council, have long had the practice of adding about 30cm of flexiable tubing when they plant new street trees. They then come around every month of so on the trees first two summers and fill the pipe with water.

So this second method involves adding a pipe or other channel way to let you deliver water deep below the new developing roots when you do the planting. The same pipe can come in handy during dry spells. However trying to add pipe below existing plant may do more damage than good. If you buy plants in tubes (they are very economic to buy that way) a great thing to do is bury the tube (unfortunatey the tube pots are seldom longer than 10cm) right beside the plant as you are planting it, you can then fill this tube with water as the plant develops.

Deep Watering : Method #1

2007-01-14T12:02:00.000+11:00

Deep watering can be very easy. For an area that yous don't want to dig over (eg around established shrubs) you can just get a garden stake, crowbar, or any strong and pointy and hammer it into the ground say 20 to 30cms around those things you wan to water deep. You can leave the whole open or put in some satur-aid or compost. Just make sure it fills up.

Some councils around melbourne are using an "air lance" (a compressed air operated probe, to do a similar job around established trees

Checking the "soil"

2007-01-13T14:54:00.000+11:00

I might have been joking before when I said I didn't know how to water. Where when and how you water depends mainly on your soil. In fact, I often watch Gardening Australia on the ABC and remember a great experiment performed by Jerry Coleby-Williams , where he oven dried three soil types and then monitored how much water they drew from a bucket of water. Read their fact sheet for more information.

So I went and had a look at my soil. Well for starters it isn't soil at all; its just muddy/silty clay with a little organic matter of the top. I figure when I was building up the garden that there was precious little cultivation back in the Cretaceous, so I didn't dig over the garden or add compost to the mud. I do know the soils where often waterlogged back then and problably not like the organic & humic rich profiles we call soil today. But I assume there was plenty of rotting vegitation on the ground, so I just add dead leaves to the surface from time to time. Even with my watering last Tuesday and a few sprinkles of rain since, it is clear my subsoil is powdery dry. The organic matter is however slightly damp. Opps that means I'll be encouraging the plant root to stay near the surface where they are much more likely to dry out. Not what I want at all.

[WATERING MYTH #1:I think a lot of people will discover this the hard way, after "doing the right thing" and mulching their gardens to "drought proof" them, only to find many prize older plants still curl up and die, because their older and deeper roots are not getting any water. All the water is in the satur-aid and mulch at the surface, only the shallow roots will benefit]

Some deeper watering is required, But how?

BLD!3 B@MB

2007-01-12T08:45:00.000+11:00

This area is to be an extension into the late creataceous, mainly palms, and also where I plan to put a rainwater tank. I needed to clear the area for the constrution of a new fence. Previously the area was a bamboo grove (I'm not the one that planted it there but it looked ok so I had left it). I had cut all the stems out in early december, and got a lot of usefull garden stakes. Now all I have to do is dig out the roots! I did some just before christmas but to be honest it has been very hot since and the cricket has been good. I did notice one or two shoots on boxing day but i am surprise at just how quickly they have shot up. (over 2 meters in 17 days)

Now the problem is getting more immediate how do I R3M*V3 TH3 BL**D!3 ST%F5

A little search for "removing bamboo from garden" in google shows a lot of discussion with varying opinions. Many suggesting it is a urban myth that bamboo is so invasive it is impossible to remove. Others maintain the real solution is not planting bamboo at all. Always the optimist I am going to test the theory that you only have to remove the thick roots (the rhizomes). So I'll keep you posted.

"Lot of gardeners have unknowingly planted running bamboos, only to have it take over their entire landscape, and I'm one of those people," master gardener Paul James admits

I do know how to water the soft tree ferns

2007-01-11T12:27:00.000+11:00

I acutally do know how to best water the soft tree ferns [Dicksonia antarctica]. Their "truck" is not a trunk at all, just a pile of root matter, which can soak up an amazing amount of water. the shape of the fronds and the way they branch also aid the collection of rain water. So the best place to water these ferns is at the crown, where the fronds grow out of this "trunk" (aka aerial root).

"The funnel-shaped rosette of fronds of D. antarctica may harvest rainfall and make it accessible to aerial roots situated at the base of fronds. This process may maintain favourable water relations independently of a subterranean root system. This proposed strategy of water acquisition is unique for a fern species and may eliminate a need for soil moisture competition with surrounding plant species."

... from Ecophysiology of the Soft Tree Fern, Dicksonia antarctica Labill by HUNT M.A.; DAVIDSON N.J.; UNWIN G.L. & CLOSE D.C.

Measurements begin

2007-01-10T16:48:00.000+11:00

As a first pass investigation I thought I should monitor how much humidity my little garden would maintain after a watering the previous night. I have a cheap desktop "weather station" (the clock battry ran out ages ago but the temperature and humidty dial still work) and placed in a shady spot. Then I just recorded the humidity every hour (yes I did sleep in! and miss the 9 am reading, but it is summer!)

I was somewhat surprised, it looks like my garden was not going to be able to maintain its humidity levels, as a natural way to fight of the heat.

10:00 AM 60%
11:00 AM 55%
12:00 NOON 40%
1:00 PM 33%
2:00 PM 27%
3:00 PM 23%
4:00 PM 20%

Time to water

2007-01-09T21:55:00.000+11:00

Seeing it is Tuesday and I live at an even numbered house I can legally water my garden tonight between 8PM and 10PM using a hose with a trigger nozzle (I guess that's a health and safety requirement incase I fall asleep an the hose!)

About 2 minutes into the watering (which only lasted 5 minutes for my little garden), I realised I didn't have a good plan how best to water. Should I soak the area around the plants or spray a fine mist. What is the best technique? I'll have to start researching that.

It was am amazing how many neighbours (on my side of the street) where also out and watering. Maybe the water restriction will have a side benefit of a renewed community spirit.

Naturally I do have a wollemi pine

2007-01-08T14:36:00.000+11:00

Discovered in 1994, by David Noble in the Wollemi National park not far from Sydney, the wollemi pine [Wollemia nobilis] is a significant mscientific discovery. The rather bizarre pine is related to the monkey puzzle pine (of south america) and norfolk island pine. There are perhaps fewer than 100 adult specimens known in the wild. After being initially considered a new species, it was eventually matched to fossils from the mid cretaceous period 110 million years ago, and was believed to have become extinct about 65 million years ago. So it pretty natural that I should have one in my creataceous garden (well in a pot in my garden)

"This is the equivalent of finding a small dinosaur alive on earth" ... Professor Clarrick Chambers, director of the Royal Botanic Gardens, Sydney, December 1994

collage of photos for my photomacro autostitch
Originally uploaded by imageo.

The photo above is not a single photo it is a photomosaic stitched together from several photos. If you want to know how this portrait of my special tree was taken, go and have a look in my photoblog, called wandering in the light

One bucket at a time

2007-01-07T13:10:00.000+11:00

One very sound and waterwise way to water pots plants is to place each pot in a bucket of water and let the soil soak up the moisture. This only takes a few minutes. It is only necessary to do this watering when the soil in the top few centimeters of the pot is dry. I learnt this from the tips for wollemi pine care website. Even in the hot recent weather this watering method last for over a week.

This is an ideal use for the "first" flow bucket collected in the shower.

Saving the first flow water

2007-01-04T22:54:00.000+11:00

A very common (and popular) way to save water is collect those first 2 or 3 litres of flow while you are waiting for the shower to warm up. All you have to go is keep a plastic bucket on the side of your shower and move it under the shower head as you start the water. Once you have the right temperature slide it out of the way as yiou get under the shower.

This water has a big advanage over other grey water collections in that it is not contaiminated with washed off dirt or soap.

It seemed like a good idea at the time

2007-01-03T11:06:00.000+11:00

My first thoughts of water saving, where of using grey water. We have a front loading machine that is supposedly water efficient, but how much does it use? It was easy to just take the outflow pipe and put it in the laundry sink and I now know a standard wash uses about 20 liters of water (which is very soapy) plus approximately another 15 litres of rise water (less soapy but still cloudy). The sink only hold around 30 litres. Still I did get a move on and bucketed out the water and avoided a serious flooding (more on that below)

The level of soap suds surprised me (we use the special front loader detergent). So instead of putting it on the garden I decided to test some on the lawn.
(PS: The lawn loved it and combined with the Christmas rains has greened considerably).

Even though I was careful I did manage to walk and splash water all through the house, so I am banned from using the bucket by bucket approach to grey water recover from now on.

My Gwondanaland

2007-01-02T18:45:00.000+11:00

saving gwondanaland
Originally uploaded by imageo.

I started developing my Cretaceous garden back in 1998. I am a geologist and had moved my office back to my home. The renovations to put the office at the front door left a long mud strip between the garage and house in which remained three sad looking tree ferns. I decided what better garden for a geologist than one based on 100 million year old plants! The garden has slowly developed, with a combination of neglect and occasional enthusiasm. it now looks what I imagine is pretty authentic

Finally, a word of warning about this blog, which really began yesterday, it will have entries going both forward and back in time, in no particular order. I will just be documenting bits from time to timae as they become relevant, some will be historic and some current. I will also try to maintain links betwen revelant items and will will maintain labels as best I can. So if any of this interest you, you are welcome to find your own pathway through the blog.

Level 3 water restrictions begin

2007-01-01T10:32:00.000+11:00

Due to the drought (and clearly a lot of inaction at government local authority levels) dam levels are low and melbourne has been put on level 3 water restrictions.

Rather than give up and let my garden dry out and die, and/or just complain. I think I should work out how best to look after my plants. I also though this might make an interesting thread on the blogsphere.

The irony of all this is that it was probably all the plant life back in the creataceous that help lower CO2, raise oxygen and begin cooling the earth. Perhaps they have more justifiable rights to water, and will make better use of it than man?

Why the strange URL name

2006-06-03T19:09:00.000+10:00

This blog actually started its life, as a journal of serial walks (my wife and I often walk various tracks and trails just doing a short part of the journey at a time, the we pick up the place we got to the next time and walk further)

Well for the long time the journal had just one entry

Our first Serial walk was long ago, in the time before blogs. We walked from Mordialloc into Albert Park.

And that is all we will tell you about it!

so I decided it would be appropriate to re-cycled that blog (rather than start something new), I trust you wont mind.

Why do I use wikipedia so much?

2006-06-03T17:47:00.000+10:00

No I don't have shares.

Wikipedia seems to me to be a fairly up to date and relevant source of a lot of the information I am posting about. I think it is a good way to let you the reader understand the scientoific terms and plant names. I also find that is largely correct, well presents the sames things I know.

Now that doesn't mean I'm saying it is totally correct, for example in matters to do with climate change. I am starting to worry that a lot, that you find on the internet may have political aggendas and in some cases be contrived mis-information. You must make up your own mind. Yet wikipedia is the most relevant place to review such issues, particularly contempary issues

When was the Cretaceous Period?

2005-11-30T22:27:00.000+11:00

The Cretaceous period was long long ago. It extended from 140 million years ago until 65 million years ago. It was the last period of the mesozoic era, often called the 'Age of the Dinosaurs'. The end of the cretaceous was marked by a mass extinction event where many species of marine and land animals, including dinosaurs became extinct as well as the majority of land plants.

There are 5 great extinction events in the geological record and the dramatic ending of the cretaceous is the last of them. There are many theories and much controversy, which I will keep away from (at least for the moment). I will leave the last word to Tim Flannery in his book "We are the Weather Makers : The story of Global Warming"

The last time the earth was afflicted (*) was 65 million years ago, when every living thing weighing more than 35 kilograms, and the vast number of smaller species, was destroyed

(* he is talking about mass extinctions)

Aren't we humans all larger than 35 kg, I know I am!

What was the Cretaceous like?

2005-11-29T22:33:00.000+11:00

I think of the cretaceous period as a time of luxuriant abundance. Tropical rain forest probably covered at least 10% of the land mass, and that land mass had been significant reduced. Many continental areas where covered by shallow seas (at least in the early cretaceous). Australia was almost half covered by such shallow seas, covering the Great Artesian Basin, the Murray Basin, Ecula Basin and Canning Basin. It is also clear that sea levels fell dramtically in the late cretaceous.

The climate was certainly hotter (there were no permanent polar ice caps) and wetter (higher humidity and possibly regular rain) but the climate may have been more benign than today. Without a strong temperature and pressure gradient (from the equator to the poles) to drive currents in the oceans and winds in the atmosphere. Weathering of the surface rocks was deep and in the few places we see that surface preserved the soils show hydromorphic (waterlogged) structure and are commonly laterites and latsols (tropical soil types). Plants where abundant but in the early cretaceous there where no flowers. Still there here massive forests with diverse flora. The angiosperms (flowering plants) evolved and spread quickly in the late cretaceous help by the increase range of insects species and particularly bees.

Ref: The Paleogeographic map is from "The Geological Evolution of Australian and New Zealand" Brown D.A; Campbel K.S.W & Crook K.A.W, Perggamon Press

The Victorian landscape in the Early Cretaceous.

2005-11-28T14:44:00.000+11:00

There are mountain ranges on both sides of the central rift valley. The streams flowing out of these ranges have built alluvial fans along the foothills. Volcanoes are active in the distance. Eruptions of these volcanoes supplied the ash and cinders deposited by the large braided river system flowing through the rift valley.

Growing on the hills are tall pine trees (1) and shorter pentoxylalean trees (2), with a small plant-eating dinosaur (3) running underneath them. It is mid-summer, so the snow on the mountains has all melted. After the flooding caused by the snow melt, the water levels in the braided river system have dropped. There are occasional tree ferns (4) on the sandbanks between the river channels. Clumps of Phyllopteroides ferns (5) are growing on the banks of the channels.

Extract from a GSAV (Geological Society of Australia, Victoria Division) booklet 'Geological History of Victoria'. Unfortunately this booklet appears to be out of print.

Geological time scale

2005-06-30T15:40:00.000+10:00

I was looking for a good graphic geological time scale to give my readrs a good view of the vastness of geological time and events but there wasn't a nice compact one, well I haven't found it yet.

Here is a link to a decent enough geological time scale prepared by enchanted, you can scroll up and down and follow links to relevant information (great for late primary or early high school kids).

This is an illustrated geological time scale, which requires a bit of clicking done but the illustrations are great.

Before it was Gwandanaland

1996-11-23T16:55:00.000+11:00

This is a pre-historic photo (you know pre-digital cameras) of my little garden before it became a cretaceous garden. Note the two original tree fern inhabitants It had a open wooden lattice cover, now removed, there are now 5 soft tree ferns to provide a more natural replacement shade canopy.

[The "BLACK PLASTIC WEED MAT" MYTH: Also note nothing else is in the garden, nothing would grow. This was mainly due the old fashion idea of using black plastic and pinebark to stop the weeds. Well its stopped the weeds and everything else by killing the soil structure (if it had any) Only the tree ferns survived, because they could get what they needed via their aerial root trunks]