Tuesday, June 03, 2014

Winter Is Here

The first day of winter arrived with a fair bit of rain and a cool south westerly wind.
But really it still isn't cold for this time of year. Maximum was 19°C (66°F)
We have had the warmest autumn on record.
May's average top temperature was around 23°C (74°F).
The last 12 months has been the hottest in 155 years of records.
The weather bureau's seasonal outlook released this week indicates all of New South Wales has a high chance of abnormal dry and warm conditions this winter.
Luckily our tanks and dams are full. But we have plenty of firewood, just in case.
Our exotic deciduous trees have decided finally to change colour (in contrast to our native trees which never lose their leaves) and the grapevines are dropping their leaves.

And at last the autumn flowers are starting to make an appearance albeit 6 weeks later than normal.

We have started pruning.  Getting the Pinot Noir done first was a priority as we have some remedial work on that block to be done. We had to replace a broken end post and need to get the netting stretched tighter. Getting the canes out of the way is the first step. We noticed there was still considerable sap 'run' when cutting the canes which is a sign of the late onset of cooler weather.
The other job is bracken (Pteridium esculentum) spraying.

Bracken had basically taken over pastureland on the south side of our creek and had reduced the available cattle feed. We had started spraying last year and 'knocked over' half of it.
Bracken is a difficult weed to control as it has an extensive, spreading root system, with rhizomes or underground stems that form a vast network in the soil and give rise to new shoots. Burning and slashing live plants just encourages additional growth.

We have found specific systemic herbicides eg. Brush-Off® or Associate® (metsulfuron methyl) with an organo-silicone surfactant to improve penetration and absorption gets the best results
The window of opportunity for getting a good 'kill' is relatively small. The plant has to be still actively growing and the fronds completely expanded so the chemical is absorbed through them and translocated to the roots. For us this means autumn before the plants 'shut down' for winter.
Luckily the warm autumn has extended the growing season this year and we are just about on top of getting the rest done. Sunday's rain will delay things a little with the creek being up making getting equipment across a little difficult. Finer weather is predicted for next week.
It takes many months to find out how successful the spray program has been as these particular weeds die a very slow death. On younger plants a slight curling and browning of the newer fronds is evident after a few weeks but the more mature ones will probably not start to visibly deteriorate until spring.
Then in the densely infested areas, the dead fronds collapse in a thick 'mat' which in turn continues to retard pasture growth.
This needs to be disposed of in some way, probably slashing and burning.

Then in the newly exposed areas, weed species that have been lying dormant eg. native tussock and snake vine (above) will immediately start growing and need to be controlled.
It's seemingly a never ending cycle.
But the success we have had on the north side of the creek makes the effort worthwhile.

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