Thursday, 23 March 2017

You can't keep a good Photinia robusta down

In another forum I included a photo of a row of Photinia robusta growing on our secondary lawn, much like the one below.
We had decided to wait and see what happens with regrowth, but were not optimistic about those close to the camera.

Looking more closely today I found signs of regrowth in most of the bushes.

 This one looks really dead?
 Not so!!  Despite the pruning scar being brown and brittle it is pumping out some leaves.
 This one survived best: check the regrowth on the RHS.
What makes this even more pleasing is that last Winter our local Swampies browsed the daylights out of these shrubs and they had only just started to recover from that.  One tough species.

I am not genusist however.  Check out this scorched Melaleuca.  Gone for all money?
 Nope, just girding its loins!



Tuesday, 21 March 2017

Ants are go

When I was a kid growing up in darkest Essex on Summer evenings we observe swarms of flying ants heading skywards.  Typically they were soon attacked by a flock - sometimes 100+ birds - of Black-headed Gulls.

This afternoon we went for a walk up the block, looking for field mushrooms.  What we found everywhere was the meat-eating ant Iridomyrmex purpureus nests were about to swarm.  Every nest we came across ...
 ... was a heaving mass of insects.  We first noticed the shimmer of the wings,
 ... but on getting closer it was apparent that the vast majority of the insects were unwinged.
They were, as usual for this species very aggressive and I soon fled, with numbers of ants all over my boots - and heading upwards.

Thus far I haven't seen any activity by potential predators.

Wildlife and washoff

We have been getting some nice rain recently (although according to my correspondent Paddy Hanrahan we need more).  This has led to an outbreak of fungi along Widgiewa Rd.
Later in the day we came across a puffball ...
 .. and some field mushrooms.
The weather has also caused frogs to be very evident in and around the house.  On a recent evening I found these 2 sitting at the bottom of a window.
 My best guess at an ID for this one was a Broad-palmed Frog (Litoria latopalmata) but on listening to its call I have never hard anything like that on our property.  My second guess is Common Eastern Froglet (Crinia signifera) which is quite common in the area.  However a Frogwatch expert has identified it as Litoria verreauxii- whistling tree frog
 The other is a Perons Tree Frog (Litoria peronii) aka The Usual Suspect).
Interestingly, this morning 21 March we went to check that the water pumped satisfactorily to the main tank and found a Peron's Tree Frog sitting on the float in the big tank.  No idea how it got there!

The early morning (around 5am) of 21 March was notable for a pretty severe thunderstorm.  This dropped 7.6mm of rain on us in about 10 minutes.  A first consequence was scouring on the drive.
 A second consequence was washing a lot of charcoal flakes into the Creek!


It seemed that most of this black stuff came down from a small gully which I have never noticed running when it was vegetated.
Looking at a topo map suggests the catchment of this gully is as shown by the red dashed line.

Switching to Google Earth gives this polygon for the catchment of the gully, which measures 2.8Ha.  
 I hope in what follows I have got my zeroes right.  2.8 Hectares is 28,000 square metres and putting 7.6mm of water on to that gives 212.8 cubic metres of wet stuff.  This resolves to 212,000 litres of water arriving almost instantaneously on a baked, largely vegetation-free landscape.  No wonder there was a bit of run-off!

(Another way of looking at 212.8 cubic metres is an ice cube 6m to a side!)

After lunch another storm came through dumping 10+mm of rain in short order (taking the day's total to 17.8mm).  Here is the gully discussed above shortly thereafter.
A few metres upstream more water was flowing in:
A few more shots of the runoff.  This is runoff channeled around the garden which ends up coming down beside the drive.
 Heavy flow in the creek.
 Runoff from the Northern side of block coming into the Creek.
For various reasons I ended up later in the day on Captains Flat Rd where Whiskers Creek goes under the road.  The soot etc hasn't made it that far yet - although I suspect the liquid has an unusual chemical composition.  The first image looks North (towards the Molonglo) ...
 ... and the second South (ie towards home).


Sunday, 19 March 2017

Regeneration

I'll begin with a snap of our house from Google Earth showing the main spots referred to below.
 The image below was taken at point 1 and shows a row of very damaged Photinia robusta.
The ones closest to the camera were very sorry for themselves, and as I pruned them most of the cut surfaces appeared seemed brown and the twigs, brittle.  However, moving up the line to point 2, the cut surfaces were greener and the twigs sappy.  Some living buds were evident!

 Going across the lawn, to point 3 this Grevillea looked rather sad.
However a lot of the twigs had little opening buds.
 Point 4 is the haunt of Callistemons.  They are not only developing vegetative growth ...
 ... but have a couple of scrappy flowers.  This may well be a stress response (last go at reproduction ...) but it looks nice.
 A similar story applies at point 5 to a flowering Prunus ...

 ... and a Westringia.

 As I moved around pruning - to try to encourage the plants to direct their energy to the viable parts - I couldn't work out why some bits were fried and others apparently OK.  I know the fire came from the West (orange arrow) but the Northern side of the plants appeared to have been saved.  This suggests fire coming from Southish (red arrow). Very strange.
Then I worked it out (or at least rationalised what happened).

A saint in a helicopter dumped a bucket of water which splashed as shown by the blue arrows.  That saved a lot more than the shrubs - so thank you (again and again).

Friday, 17 March 2017

The sun also sets

I went to a meeting at the Community Hall last evening.  On the way I noticed a large cloud bank sitting on top of Tallaganda.
 I wondered if that might lead to some rain in our direction but it didn't seem to.

After the meeting the sun was setting.  This is looking West from the Hall car park.
 The sky was a little lighter but still quite spiffy looking East towards Balcombe Hill.
 As I drove home I stopped to take a snap of the Taliesin Hills.  Again the amount of cloud made me wonder about more rain.
 A slightly different view of Taliesin from the top of our drive.

Thursday, 16 March 2017

Getting an angle on sines of life

It is quite obvious that the grass is now growing nicely in many of the burnt parts of the countryside. At the very least we now have a checkerboard of green and black (with a largely brown superstructure).

There are other indications of nature fighting back.  Beside our drive, right outside the kitchen window we have some Colchicums (wrongly called Autumn Crocus) giving a burst of cream:
 With a few added raindrops (14mm in the past few days) they are very pretty.
 In the sunroom bed some Acanthus are shooting again.  Hopefully they'll capture a serve of energy before Uncle Frost comes to kill them off.
 A little down the drive Frances noticed some bright green in a Eucalyptus (I think E. meliodra - Yellow Box).
 Yes!  It the first epicormic growth we have noticed thus far.
A day later Frances noticed that one of the plum trees is shooting ...
 .. and astonishingly, flowering!

As an aside, having mentioned frost above I have had a look at the dates of the first frosts as recorded for Carwoola.  
  • I first used the broad definition of a frost (temperature at screen height less than +2oC) which equates to a ground temperature of 0oC).  This shows that in 11 of the 24 years for which I have measurements a temperature that low has been recorded before the end of March.  In a further 10 years it has been recorded by 15 April.
  • Looking at the tighter definition  (temperature at screen height less than 0oC) shows that only 9 years have a temperature that low by 15 April and in 8 years we had to wait until May.