[Arid_gardener] Re: Palo Brea Problems

[Olin Miller]

One natural defensive mechanism of drought-evading, desert-adapted trees 
is that they conserve moisture by cutting down on transpiration as 
evidenced by generating smaller and fewer leaves.  Thirty two gallons 
every few weeks is not very much water.   The irrigation frequency seems 
to be okay but you might want to water for longer periods to ensure 
water penetration down to 3 feet each time you irrigate.  You might also 
want to add a few emitters.  Studies of trees about 10 years old show 
that the feeder roots develop only in the area below emitter placement. 
For tree care, Refer to, "AZ1048 Care of Desert Adapted Plants " at
http://cals.arizona.edu/pubs/water/az1048.pdf
and
http://www.cityofmesa.org/utilities/conservation/landscape__watering.asp

Olin Miller
Master Gardener Volunteer, Maricopa County AZ

"The opinions or statements expressed herein are my own and should
 not be taken as a position, opinion, or endorsement of
the University of Arizona."
======================================================

----- Original Message ----- From: "Joe Durnell" <jdurnell at gmail.com>
To: "Olin Miller" <derGartenArzt at worldnet.att.net>
Sent: Thursday, May 04, 2006 11:47 PM
>...
The yard is decomposed granite, with no plastic.  It is watered by 4
adjustable emitters spread around the canopy.  I have them opened wide,
which I think is 4 gal/hr.  I water for 2 hours every couple of weeks in 
the
warm weather, less during the winter.  We planted three palo breas ten 
years
ago - ironically this one took off the quickest and grew to a nice size.
However while the other two are thriving this one is struggling.

I was hoping that perhaps the small leaf size and pale coloring would
provide a clue to what might be wrong.  My rain gauge measured over 12" 
of
precipitation last year, so ironically we're not in so much of a drought 
in
our neighborhood.

Thanks!



On 5/4/06, Olin Miller <derGartenArzt at worldnet.att.net> wrote:
>
> More information would have been helpful, e.g.
>
> Is the tree planted in a yard of gravel or decomposed granite,  If 
> yes,
> is there plastic under the gravel under or near the canopy that would
> deprive the roots of oxygen?
>
> With our current drought, many native trees as well as the cultivars,
> should water regularly.  How frequently and how much water does the 
> tree
> receive?  Is there a basin for the water?  If yes, does it extend to 
> the
> edge of the canopy.  Or is it on a drip system?  If yes, how many
> emitters?  Where are the emitters located.  What is the gap rating of
> the emitters?
>
> Olin Miller
> Master Gardener Volunteer, Maricopa County AZ
>
> "The opinions or statements expressed herein are my own and should
> not be taken as a position, opinion, or endorsement of
> the University of Arizona."
> ======================================================
>
> ----- Original Message ----- From: <jdurnell at gmail.com>
> Sent: Saturday, April 29, 2006 12:48 PM
> > Joe Durnell,  85260,  jdurnell at gmail.com
> > My 7-10 year-old palo brea has not leafed out well for the past two
> > springs/summers.  The leaves are coming out very small and pale, and
> > even the bark appears a paler green than usual.  Blooming is not 
> > very
> > prolific either.  Before this there did not appear to be any 
> > problems.
> > I do live in a part of Scottsdale that gets nipped by frost a few
> > nights a year, and have noticed some branch die-back on this tree.