Sunday, 18 March 2007

Rain Water Absorption Rates on Bare Soils

In Darryl Cluff’s booklet titled “Farming Without Farming” ISBN 0-9751118-09 Published in 2003 and available through Stipa Native Grasses Association, Inc. he comments at one point that as a genera rule on land which has an effective water cycle in operation one should expect to see 1 cm of soil profile moisture created from every 1 mm of rainfall. Thus where the soil profile is dry and 5 mm of rain falls there should be 5 cm of soil moisture in the soil, after allowing time for infiltration.

Recently on Ochre Arch we received 9 mm of very gentle rain over a period of 5 hours. Pretty much all of the soil on the property had zero grass ground cover, and prior to the rainfall event the soil profile was extremely dry. Approximately 1 hour following this event I headed off across a couple of paddocks with shovel-in-hand to see how much moisture had been absorbed by the soil.

On the flatter country in one place where the soil surface was not capped I dug down to find that there was about 9 cm of moisture penetration – consistent with Darryl’s comments, and evident in the accompanying photograph.
At another place on the property I dug to see what the soil moisture profile was underneath one of the well-worn sheep tracks. The results here were markedly different, and the moisture profile was only around 1 cm – almost 90 % less than on the flatter country. See second photograph. This was despite the fact that there had been considerably more water in the sheep track, what with the runoff of water along the sheep-track that had occurred. On reflection, the primary feature of the soil surface in the sheep-track was compressed / capped soil, making the bottom of the track very much like an impervious trough. The underlying cause of the compaction was over-grazing.

The other critical factor in rainfall effectiveness is retention of water in the soil post the rainfall event. Given there is was no ground cover on Ochre Arch the loss of moisture in the days following was extreme (especially given hot weather) and pretty much all of the moisture had evaporated within 48 hours.

For those wishing to learn more about the basics of the way the water cycle works, there is an excellent presentation on the website. Click HERE to go directly to the presentation.

Unexpected Results from Feral Cat Trapping Attempt

Recently on Ochre Arch we noticed some feral cats near the house and shearing shed, so I decided to have a go at trapping them in the interest of encouraging birdlife around the place. As a ‘lure’ to the trap I placed a rabbit that I’d shot earlier in the day inside the trap, and set it about 20 metres from the house closest to our bedroom. The theory was that when and if we did catch something we’d hear it in the trap, and I’d be able to quickly and humanely deal with whatever was caught.
It transpired that the night in question was incredibly windy and noisy. We heard nothing during the night other than the wind belting through the trees near the house. In the morning I ventured out, and was bewildered to see that the trap had been moved about 5 metres, turned end-over-end and on its side, and that that the trap door was open and the rabbit had gone. Close inspection of where the trap had been set revealed substantial scratch marks on the ground, which to me were most probably made by a fox. Whatever it was that managed to do what it did to the trap and remove the rabbit certainly deserves respect for cunning and persistence if nothing else.
The next day I was recounting the above to my mother, who explained that my father used to use milk in a bottle lid to lure feral kittens from their hides. After several days they became accustomed to the practice and could be approached and trapped. Armed with this information I decided to set the cat-trap up in the shearing shed (not accessible to foxes) with a bottle lid of milk in it. On the first night the trap was untouched. However on the second morning when I entered the shed the trap had been triggered but at first glance appeared to be empty. On close inspection I was amazed to find a large and healthy Blue-tongue Lizard near where the milk had been placed. It quickly scampered away to safety on release.
Some days later I shared the above information with a neighbour who explained that snakes love drinking milk, so it’s possible all reptiles do.

Needless to say my feral cat trapping exercise did not produce the results I’d hoped for, but most certainly added to my own knowledge, not to mention respect for the ingenuity of foxes!

Friday, 16 March 2007

“Blue Tardis” Camp Shower Successfully Constructed

Our farm is bit light on in terms of some of the ‘normal’ facilities most people expect to see on a farm, or house for that matter. We’ve not had a shower set up, so have tended to visit family or neighbours places or alternatively shower in the open using the Coleman Camp Shower we bought some years ago. The challenges with this latter option include lack of privacy, wind chill factor and rapid evaporation.
On our last trip we got a bit creative and have now constructed what I’ve named the “Ochre Arch ‘Blue Tardis’ Camp Shower Extraordinaire” as you will see in the photographs.
The "ingredients" and construction process is outlined in the following ‘recipe’.

"Ingredients" for constructing the shower surround
* Flat impervious surface on which to locate the structure.
* Second-hand overhead tank stand (doesn’t everyone have one of these!)
* Material for covering the tank-stand (in our case, blue tarpaulin)
* Fencing wire & pliers
* Soap / shampoo shower accessories rack
* 3 clothes pegs
* 1 clamp, large enough to go over the pipe of the tank stand
* Scissors
* Wooden wedge
* Bucher’s hook (again, doesn’t everyone have one of these!)
* Tape measure or string (for measuring tarpaulin)

Instructions or constructing shower surround
* Place tank stand upright on impervious surface, and stabilize using the wooden wedge under one of the tank stand ‘legs’.
* Cut tarpaulin to size using scissors. The width needs to be sufficient to go from the ground to about 600 mm above the height of the likely tallest person to use the shower / the top of the top rail of the stand. The length needs to be long enough to go right around the outside of the tank stand, with about 300 mm overlap. Cut a section from the top of the overlap so that it can be folded over the top rail of the stand and pegged in place.
* Anchor the tarpaulin on one corner of the stand (at where you want the entrance point) by folding the overlap flap over the top rail and hold in place using the 3 clothes pegs.
* Wrap the rest of the tarpaulin around the stand, and anchor in place using the clamp on the pole where the overlap occurs.
* Use pliers and wire to install a hook on one of the poles inside the stucture
* Place soap / shampoo shower accessories rack on the hook
* Hang Butcher’s hook over one of the rails – for towel and clothes

"Ingredients" for the shower mechanism
* 2 X 20 litre plastic containers. In our case we sourced 2nd hand ones from our local Hammersley-Direct outlet, for the price of around $1 each. Select containers that have had ‘environmentally friendly’ substances in them, such as Eucalyptus based oils (Ask the supplier for advice here!)
* Coleman Camp Shower
* 4 X D Size batteries (to power the Camp Shower)
* Fresh water sufficient to fill one of the 20 litre container
* Cordless drill with 5 mm (or thereabouts) bit

Constructing the shower mechanism
* Install batteries in the Camp Shower battery container
* Use cordless drill to create 2 holes each abut 80 mm in diameter in the top of one of the 20 litre plastic containers

Water Heating
* Fill other 20 litre container with fresh water early in the morning, place screw cap on it, and leave it in the sun all day. This assumes evening shower use. From our experience 1 X 20 litre container is sufficient for 2 people to comfortably (separately!) shower.

Getting ready to use the shower
* Locate the plastic container with the 2 holes in the top in one corner of the shower structure.
* Poor heated water from the other container into the one with the 2 holes in the top
* Place ‘pump’ of the camp shower in one of the 2 holes in the container that now has water in it.

Using the shower
* Turn camp shower on via switch on the top of the battery holder
* Place shower nozzle in the other hole in the top of the 20 litre container when not actually using it for wetting i.e. leave the pump going but place the nozzle in the hole so that water can be recycled.

Other tips
* We use wooden slat ‘thingies’ to stand on whilst showering and another just outside the shower for feet draying.
* For nocturnal shower use we suggest the purchase of one of those solar powered garden lights. These cost about $10-15.

In closing
Patent pending - just kidding. If following the above instructions doesn’t work for you, don’t blame me! Enjoy!

Monday, 12 March 2007

Matching Stock Numbers to Available Feed - Outback Style

Last month I attended a friend’s “Surprise 60th” birthday party at which I had the pleasure of being re-acquainted with Barry Sommerlad, a great bloke who I had the pleasure of first meeting in late 1979 when I made my decision to enter the world of financial services (or just plain 'banking' as it used to be known then). During the course of our conversation at the birthday party Barry shared with me a fascinating experience he’d had in his “Bank Manager days” in connection with the word ‘perish’. After the party I contacted Barry and invited him to document his recollections in more detail, and invited him to send it to me for publishing as a guest blog article. Here is the content from what Barry has now sent to me. Thanks Barry!

“Approximately 20 years ago, I had the opportunity to visit Isis Downs, near Blackall in central western Queensland.

The Isis Downs’ website details that in its heyday in 1912, the property comprised 2,340 sq kms and had a carrying capacity of up to 230, 000 sheep. Following the Second World War, the area was reduced to 1,227 sq kms as a result of soldier settlement. In 1987, the Packer family, through its Consolidated Pastoral Co., acquired Isis Downs and a further 9 surrounding properties to increase the holding to 2,327sq kms. It now has an estimated carrying capacity of up to 120,000 sheep and 21,000 cattle, or 17,500 cattle only. In more recent years, it is believed the focus has been on cattle due to the greater stability in that market sector.

My visit occurred just before the sale to CPC took place. The then owner gave me a run-down on the history of the property. It had boasted what was believed to be at one time the biggest shearing shed in the southern hemisphere, and for its time had state-of-the-art electric shears. There were the remains of an articulated truck/wagon/trailer for transporting a huge number of bales following shearing, to the nearest rail-head. The vehicle had an articulated driveshaft running from wagon to wagon, and while it had a huge carrying capacity, it was very slow and cumbersome and enormously heavy, and the merest hint of rain saw it sink into the ground, not to move until it dried out.

The owner had read all of the journals and diaries left by former owners and managers, and there were a number of entries in the earlier years that intrigued him. Some entries referred to the quality of “perish” that had been achieved during the year. The journals gave no hint as to what “perish” meant, and the owner had not encountered the description in his experience on other properties in other parts of Australia. He therefore sought assistance from neighbours who had had long-term experience in the area, and was given the following explanation, which is as I recall it.

If there had been a good start to the season, sheep numbers would be increased to the absolute maximum that the property could sustain, a figure well beyond, the normal carrying capacity. If the season was good enough to sustain the increased sheep numbers then “well-and-good”. However, if the over-stock number could not be maintained, then obviously sheep had to be culled and numbers reduced in a manner deemed at that time to be, on the balance of various factors, as humanely as possible. Due to the remoteness of the property, it was not practicable to truck the sheep elsewhere, and if the season was poor there then there would be little market for surplus stock.

The culled sheep were put-down in the following manner. A huge enclosure would be constructed with fences made of piled-up scrub and brush. The culled sheep would be driven into the enclosure, and the entrance filled in with scrub and brush. Over a relatively short time, the sheep would perish from hunger and thirst. Further “perishes” would take place as needed.

It is likely a good “perish” involved as few sheep as possible and a bad “perish” a significant reduction in sheep numbers. The practice at the time was regarded as an effective means of managing stock numbers and maintaining sustainability.

When this was explained to my host/owner, something else twigged with him. When he flew over his property to inspect dams, bores, tanks, windmills, fences etc, following rain he was intrigued by the large geometrically-shaped areas where the vegetation growth was much better. These had been “perish” enclosures and many decades later, the fertiliser provided by the deceased sheep continued to benefit the land.”

Sunday, 4 March 2007

Grenfell district in early European settlement & subsequent times

After reading my recent blog titled “Ochre Arch Land Monitoring Sites Established” one of my contacts in the USA asked that I create a blog giving more detail on the history of the Grenfell district (in New South Wales, Australia) where "Ochre Arch" is located, including information on the landscape, vegetation and fauna when Europeans first settled the area. I referred the request to my uncle, Peter Diprose, who kindly researched the topic and documented his findings for me. What follows is what he sent through to me, which I’ve made into a ‘guest blog’. Thanks Peter!

Grenfell is located 380 kilometers West of Sydney, and is 350 metres (1150 feet) above sea level. The average rainfall based on personal / family records over 120 years is 21 inches per year (535 mms), varying from 9 inches to 44 inches.

The area was first settled around 1835 by “squatters” (ranchers) coming west from the eastern seaboard. The area was open woodland – widely spaced trees including eucalypts, some acacias, pines (callitris calumallaris and callitris calcarata) with a range of woody shrubs. The trees were fairly widely spaced with good grass between. Water was supplied by springs and, in good years, semi-permanent creeks.

When the first settlers arrived they were gratified to find wide open grassland with a good sprinkling of shade for their stock. The indigenous fauna included red and grey kangaroos, various wallabies, koalas, wombats, bettongs and bilbies and occasional quolls. It must be noted that all Australian native animals are soft-footed, unlike horses, cattle, sheep and goats, so that over time what were useful pastures for stock began to deteriorate and only the coarser grasses remained. The softer, more nutritious varieties couln not stand the hard hooves of the stock. (Editors note: There are some who argue it is not the ‘hard-footed’ herding animals that caused the damage to pasture species, but rather the way in which they were managed).

The introduction of fences (and the arrival of land laws!) and the consequent ability to control grazing helped to maintain reasonable grazing. It was not until imported grass and legume species were introduced that stock husbandry was assured. When gold was discovered in 1865 the local stock industry received a boost – there were thousands of miners and the usual entourage to feed.

By the late 1800’s farming had begun – mainly wheat and barley. With the introduction of farming and as a result of the “Great Drought” (1895 – 1915) accompanied by an economic recession most of the large stations (ranches) had become uneconomic and if the owners did not voluntarily sub-divide the governments of the day resumed them for “closer settlement”, that is for farming. Thus the day of the large holding was over in the district. Even though the seasons were drier than usual, by 1900-1910 Grenfell had become known as the “granary of the Southern Hemisphere”. In 1901 Rail arrived in the area and this made transport of produce much easier, and farming became profitable.

After WW1 there was an economic boom in agriculture – felt through the larger world. More sub-division of property occurred to cater for the demand for farms. As a result, by 1930 and the Great Depression, many of these farms became untenable, and only the better managers survived. A similar situation occurred after WW2 and this put more pressure on the land. Although some farmers abuse their land, most of our problems have been a result of bad government policy. Currently, land is being aggregated by better managers, and this may ease the pressure on the land. Hopefully we will have learned a lesson – but one can’t help wondering if, as the world population continues to increase at an alarming rate, we will survive.