Friday, February 27, 2015

Zenith Zoysia Seed to Develop A New Oval in the Tropics - Part 3 – Mowing Time

One of the milestone events in any new turf development is the mow………..yes, the first mow.
zenith zoysia coverage at about 6 weeks from sowing

For this site it was 45 days after sowing, and although a bit large we opted for a domestic rotary mower, which allows a bit of a closer check on what is going on with the turf, ease of manoeuvre of equipment, but with a greatly extended time requirement.

The cut went well…………., cutting the area back quite short. No serious problems and a very smart appearance.

The next mow was this past week, at 59 days from sowing, say at 8 weeks, and two weeks after the first cut.  This time however we used a zero turn front deck mower, adjusted to cut short, but not absolutely the shortest, and a fraction higher than the first cut.  We will probably continue with mowing at 10 – 14 day intervals for the next month.
After mowing at 8 weeks note small areas now covering in 

The turf has continued to grow well, and will receive a small fertiliser boost in the next 7 days, weather dependent. 

In the meantime we continue to remove grassy weeds, especially focussing on Bothriochloa spp.  Some are new plants, some are plants around the outer areas of the oval where they have had almost zero competition since the original sowing, and some very large clumps of runners that seem to have recovered from the glyphosate spray.  A big job, but it is almost inevitable with ovals that a major hand weed is needed.  We expect to have to do more over the next few weeks, but at this stage a very substantial number of plants – small to medium sized have been removed.  There is no easy herbicide solution to selectively kill Bothriochloa spp in turf.

A further spray to remove a few remnant legume weeds long with some other broad leaved weeds and some sedges will be needed as weather allows [currently wet and raining most days], and it may be possible to spot or strip spray for these weeds, rather than the entire oval.

The big change is the rapid growth of runners extending laterally in the zoysia.  These runners are very noticeable around the edge of the oval where the sown Zenith was either a bit thin or had not been sown out past the oval boundary.  These areas are rapidly being colonised by the Zenith as new runners spread quickly.

The odd small bare area on the oval is also being covered with these runners, and very quickly too, once they started, which was after the first mow.  Zenith and especially Compadre are well known for excellent lateral growth as is being seen with these new runners now covering the bare spots.
Runners rapidly covering a bare spot on oval

Runners now colonising an area off the edg eof the sown oval

It augurs well for over 95% coverage soon.
Getting close to 95 %cover on many parts of the oval now

Wednesday, February 11, 2015

Renewable Energy Comes to Mining in Remote Australia - BIG TIME.

Sandfire Resources has recently signed a deal with Brisbane-based Juwi Renewable Energy to build a $40 million solar power station at its DeGrussa copper project near Meekatharra to help power the mine and its processing operations.

The project had potential to establish DeGrussa as an industry leader in the use of renewable power for mining and processing operations.  Sandfire said its cash contribution to the project would be less than $1 million, with Juwi to arrange project funding and own/ operate the facility.

The station will utilise a 10.6-megwatt solar array comprising 34,080 solar photovoltaic panels [ on 20 ha near the mine and concentrator] that track the sun coupled with a 6-megawatt battery, and will be the biggest integrated off-grid solar array in Australia, and one of the biggest used in the mining industry anywhere in the world. The solar power station will be integrated with the existing 20-megwatt, diesel-fired power station at DeGrussa, which is owned and operated by Kalgoorlie Power Systems.

It will be structured to maximise the consumption of lower-cost solar power, thereby reducing reliance on diesel, however the diesel power station will continue to provide base-load power to the DeGrussa mine.  The project is expected to achieve savings in diesel fuel and will deliver a significant environmental benefit for DeGrussa, reducing its carbon emissions by an estimated 12,000 tonnes a year.

Sandfire's managing director Karl Simich said the company had been working on the solar power initiative since 2013, with the project representing an attractive opportunity to participate in a low-risk renewable energy initiative with a minimal capital requirement.  It is interesting to see this announcement now, following a recent article bemoaning use of solar power in remote operations in Australia, especially in comparison to mining in Chile.

He said the project would not affect the efficiency or safety of existing operations, and would allow the company to contribute to the broader challenge of reducing CO2 emissions and potentially reducing operating costs. "We are continuing to explore other options to reduce our energy costs, including using alternatives such as compressed natural gas for gas-fired power generation," he said.

Juwi managing director Andrew Drager said the solar photovoltaic system would provide the majority of daytime electricity to substantially reduce the mine's dependence on imported diesel.

Saturday, February 07, 2015

Zoysia CAN Grow Tall

In the tropics when the weather turns from dry to can get very wet, and stay that way for many weeks

Even zoysia can grow to a tall sward, under those conditions.

Look at the Zoysia matrella shown here being cut with a residential model rotary mower.

About 8 weeks plus since it was cut and the weather was very monsoonal, and with the near constant rain it was just not possible to get the area cut..........but it had to be done.

As soon as a weather break occurred it had to be mown.

So with the mower on a moderate height the lawn was cut.  Once to get the top growth down and then a following cut in a day or so to lower the cut again.

Not ideal and there will need to be some further mowing soon.  BUT even  if zoysia is neglected and grows tall [ was about 150mm high] it can be resurrected successfully.

For most situations, especially in a normal residential area, mowing at 15 -30mm is normal, using a rotary mower.  Better lawns can be cut lower, but a cylinder mower is preferred once cutting below about 15 - 20mm. 

Tall zoysia - needing to be cut