[ Sorry folk. Had to break the threading. NX choked on the
References line which had grown to near infinity.]

In article ,
"Jim Webster" wrote:

Gordon Couger wrote in message
.. .
[snip]
I am sure that you do some irrigation but the size of them and the
varying
climate and soils you go by expert experiance more than trying to
match all the equations to you climate that varies by the mile.

All those water budget equations don't take into account the rain
fall
anyway so they are only truly valid in the desert. To use them you
have a number of K factor in them

it did rather strike me that doing one for an area with five feet of
rain was something of a waste of time.

Each to his own of course, but I know of plenty of places around here
where farmers getting 80 to 100 inches of rain per year still find it
useful to irrigate at times to ensure optimum production of pawpaws,
bananas, and sugar cane.

Mind you, I must admit they probably don't decide when or how much by
using a water budget -- more likely kick the ground, look at the sky,
and say "Hmmm... better put on a couple of inches tomorrow." Much as
Gordon says above.


Cheers, Phred.

--
LID

Phred writes

Each to his own of course, but I know of plenty of places around here
where farmers getting 80 to 100 inches of rain per year still find it
useful to irrigate at times to ensure optimum production of pawpaws,
bananas, and sugar cane.

I'll believe that, in fact I'd expect it. The total rainfall is a bit of
a red herring since it cannot distinguish between jim, in a constant
rain 24/7/365 and with low transpiration rates, and a seasonal monsoon
with a 10 month dry period and huge transpiration despite both getting a
60" rainfall. One would love to see the sun and occasional days over
20C, the other needs irrigation!

Mind you, I must admit they probably don't decide when or how much by
using a water budget -- more likely kick the ground, look at the sky,
and say "Hmmm... better put on a couple of inches tomorrow." Much as
Gordon says above.

I don't know. When I grew spuds (not my farm) I had a shallow, wide
cylindrical glass container that I filled up and left outside sometime
in early may when the field drains had stopped running for a week or so.
When about 1.5" had evaporated I started considering irrigation
(depending on likely weather to some extent) and when I had applied an
inch, I topped it up with an inch. This gave me a crude estimate of
moisture deficit. Of course it quite often overflowed if a wet spell
came. The most interesting thing was that locally it was known that one
side of the farm had a 36"+ rainfall, and the other a 25". I therefore
had one in each field (probably 1/2 mile apart one year). One side (in
quite a dry year, admittedly) was irrigated pretty well on about a
1"/month basis for six weeks or so but the other side never even reached
the trigger point.

To be honest though, after only two years I hardly needed it, being able
to judge about as well just by digging an 18" hole in the field and
seeing how dry it was at depth. Probably better, now I think about it as
this made allowance for soil holding capacity.

--
Oz
This post is worth absolutely nothing and is probably fallacious.
Note: soon (maybe already) only posts via despammed.com will be accepted.

Phred wrote in message
...
anyway so they are only truly valid in the desert. To use them you
have a number of K factor in them

it did rather strike me that doing one for an area with five feet of
rain was something of a waste of time.

Each to his own of course, but I know of plenty of places around here
where farmers getting 80 to 100 inches of rain per year still find it
useful to irrigate at times to ensure optimum production of pawpaws,
bananas, and sugar cane.

By the look of the crops you have far higher transpiration rates. Our
staple crop is grass.

Mind you, I must admit they probably don't decide when or how much by
using a water budget -- more likely kick the ground, look at the sky,
and say "Hmmm... better put on a couple of inches tomorrow." Much as
Gordon says above.

I suspect when you know your area and have farmed there for a generation
or so, you get a feel for the place. No point in putting on water if you
reckon it is going to blow in rain over the next couple of days.
Irrigation water costs money, rainfall is free.


--
Jim Webster

"The pasture of stupidity is unwholesome to mankind"

'Abd-ar-Rahman b. Muhammad b. Khaldun al-Hadrami'




Cheers, Phred.

--
LID

Jim Webster writes

By the look of the crops you have far higher transpiration rates.

Our staple crop is grass.

No Jim,

Your only crop is wet grass.

--
Oz
This post is worth absolutely nothing and is probably fallacious.
Note: soon (maybe already) only posts via despammed.com will be accepted.

Michael Percy wrote in message
...
Jim Webster wrote:

a fine summer in the SE and you could get up as high as 20

Sure, I'd say in a fine summer (warm, sunny) you could get potential
transpiration rates rather higher than that in south england!

and as I also said, and you snipped

"if the figure was important someone would probably publish the
figures"


--
Jim Webster

"The pasture of stupidity is unwholesome to mankind"

'Abd-ar-Rahman b. Muhammad b. Khaldun al-Hadrami'

Oz wrote in message
...
Jim Webster writes

By the look of the crops you have far higher transpiration rates.

Our staple crop is grass.

No Jim,

Your only crop is wet grass.

we have been know to make hay.

Made a bit second cut this year, in big bales, not bad stuff.

--
Jim Webster

"The pasture of stupidity is unwholesome to mankind"

'Abd-ar-Rahman b. Muhammad b. Khaldun al-Hadrami'


--
Oz
This post is worth absolutely nothing and is probably fallacious.
Note: soon (maybe already) only posts via despammed.com will be
accepted.

"Michael Percy" wrote in message
...
Jim Webster wrote:

a fine summer in the SE and you could get up as high as 20

Sure, I'd say in a fine summer (warm, sunny) you could get potential
transpiration rates rather higher than that in south england! But you are
right, east anglia would be about 20 inch ETpot in a typical summer ...
with the ETpot for the winter yet to add.

No wonder that you psycho buddy chilled when it dawned to him out what it
was, he had been wishing for .. to be 'blessed' with just 10" of rainfall
spread evenly through the year to roughly 'match' evapotranspiration
....lol... in a 20" ETpot area.

I don't know if water evaporates at 20 degrees My record high temperature
is 50
C. For water budgets try google and search for 'cotton water budget' you
will get plenty and 'UK wheat "water budget" ' brings up a bunch as well.

Gordon

"Oz" wrote in message
...
Phred writes

Each to his own of course, but I know of plenty of places around here
where farmers getting 80 to 100 inches of rain per year still find it
useful to irrigate at times to ensure optimum production of pawpaws,
bananas, and sugar cane.

I'll believe that, in fact I'd expect it. The total rainfall is a bit of
a red herring since it cannot distinguish between jim, in a constant
rain 24/7/365 and with low transpiration rates, and a seasonal monsoon
with a 10 month dry period and huge transpiration despite both getting a
60" rainfall. One would love to see the sun and occasional days over
20C, the other needs irrigation!

Mind you, I must admit they probably don't decide when or how much by
using a water budget -- more likely kick the ground, look at the sky,
and say "Hmmm... better put on a couple of inches tomorrow." Much as
Gordon says above.

I don't know. When I grew spuds (not my farm) I had a shallow, wide
cylindrical glass container that I filled up and left outside sometime
in early may when the field drains had stopped running for a week or so.
When about 1.5" had evaporated I started considering irrigation
(depending on likely weather to some extent) and when I had applied an
inch, I topped it up with an inch. This gave me a crude estimate of
moisture deficit. Of course it quite often overflowed if a wet spell
came. The most interesting thing was that locally it was known that one
side of the farm had a 36"+ rainfall, and the other a 25". I therefore
had one in each field (probably 1/2 mile apart one year). One side (in
quite a dry year, admittedly) was irrigated pretty well on about a
1"/month basis for six weeks or so but the other side never even reached
the trigger point.

To be honest though, after only two years I hardly needed it, being able
to judge about as well just by digging an 18" hole in the field and
seeing how dry it was at depth. Probably better, now I think about it as
this made allowance for soil holding capacity.

I just got through having coffee wiht the guy that invented the neutron soil
moisture probe. He is an retired agronomy professor here and fellow amateur
radio operator. I spent the better part of 6 months working on a capacitive
probe to measure soil moisture for Ag Engineering. The current most popular
method is time domain refectomotmy. My wife's farmer uses a steel probe
forced into the ground and a lot of experiance. Cotton also is self
indicating. It normally shuts down in the heat of the day and wilts even
with plenty of water so you can tell by the time of day and the temperature
pretty well when it needs watering.

There is a very large market for a good soil moisture probe and it is a very
difficult problem because it is impossible to keep the soil in contact with
the probe and all the electrical method the inverse square law applies so
any small change close to the probe is greatly magnified. The Neutron probe
is the gold standard but getting the permits for it is a real bitch and
there is no easy way to test for radiation leaks.

I highly reliable soil moisture probe that cost $50 would increase the
bottom line of most irrigated crops 5 to 15%.

Michael Percy wrote in message
...
Jim Webster wrote:

and as I also said, and you snipped

"if the figure was important someone would probably publish the
figures"

One can complain from now until hell freezes over that bits and pieces
are
snipped on usenet. Why do you think that particular piece of junk is
worth
repeating? Don't tell me you are proud of it!

I see you still haven't got an answer so just go for personal attacks.


--
Jim Webster

"The pasture of stupidity is unwholesome to mankind"

'Abd-ar-Rahman b. Muhammad b. Khaldun al-Hadrami'


Mike

Gordon Couger writes
For water budgets try google and search for 'cotton water budget' you
will get plenty and 'UK wheat "water budget" ' brings up a bunch as well.

It does, but look at the abstracts:

Gateway for **Indian** Agriculture - Tools
.... Soil Water Budget Calculator (JAVA APPLET) -. ... Crop Gross
Margin Calculator. Winter Wheat Calculator. ... Holstein UKI Bull
Database - Holstein UK and Ireland, UK. ...web.aces.uiuc.edu/aim/digli
b/india/tools.htm - 18k - Cached - Similar pages

Conservation Ecology: Linkages between water vapor flows, food ...
.... yield and water use efficiency of spring wheat and barley. ...
Cambridge University Press, Cambridge, UK. ... Water budget of an
eastern deciduous forest stand. ...www.consecol.org/vol3/iss2/art5/app
end4.html - 19k - Cached - Similar pages

ALN No. 45: Allan: Water Stress and Global Mitigation: Water, ...
.... for food is the "big" water in any national water budget. ... A
hectare of wheat, requiring about 5000-6000 cubic ... at the
University of Middlesex, London UK in 1996 ...**ag.arizona.edu**/OALS/
ALN/aln45/allan.html - 25k - Cached - Similar pages

Planet Ark : FEATURE - Water woes plague US-Mexico border
.... in recent years and now demand that California live within its
water budget. ... the landscape, taking water to thirsty farms where
alfalfa and wheat drink 67,000 ...www.planetark.org/dailynewsstory.cfm
/newsid/ 16464/newsDate/18-Jun-2002/story.htm - 28k - Cached - Similar
pages

Planet Ark : FEATURE - Water woes plague US-Mexico border
.... and now demand that California live within its water budget. ...
to thirsty farms where alfalfa and wheat drink 67,000 ... UK: UK
consumers uneasy over GM crops and ...
www.planetark.org/dailynewsstory.cfm/ newsid/16464/story.htm - 28k -
Cached - Similar pages

National Water and Climate Center - Irrigation Information Sites
.... Irrigation Scheduling - Cranfield UK Irrigation Association ...
International Maize and Wheat Improvement Center ... Plant,
Atmosphere, and Water Budget Model USBR ...
http://www.wcc.nrcs.usda.gov/nrcsirr...e_bookmark.htm - 51k - Cached -
Similar pages

A further troll through and all I found was references to publications
(not on the net) and the UK sources that looked plausible only had US
data.

--
Oz
This post is worth absolutely nothing and is probably fallacious.
Note: soon (maybe already) only posts via despammed.com will be accepted.

Michael Percy wrote in message
...
If you have a valid point you shouldn't need to.

Mike

exactly, if you had a valid point you shouldn't need to sink to making
personal attacks. I'm glad you have finally seen the error of your ways.


--
Jim Webster

"The pasture of stupidity is unwholesome to mankind"

'Abd-ar-Rahman b. Muhammad b. Khaldun al-Hadrami'



Jim Webster wrote:


Michael Percy wrote in message
...
Jim Webster wrote:

and as I also said, and you snipped

"if the figure was important someone would probably publish the
figures"

One can complain from now until hell freezes over that bits and
pieces
are
snipped on usenet. Why do you think that particular piece of junk
is
worth
repeating? Don't tell me you are proud of it!

I see you still haven't got an answer so just go for personal
attacks.

Michael Percy wrote in message
...
Gordon Couger wrote:

I don't know if water evaporates at 20 degrees

Oh yes you do, yes you do....

My record high temperature is 50 C.

Now that's pretty hot. I bet it can also get pretty cold at night in
New
Mexico!

For water budgets try google and search for 'cotton water budget'
you
will get plenty and 'UK wheat "water budget" ' brings up a bunch as
well.

Not to mention what 'tze water budget' brought up on this here old
thread...

obviously you missed the bit that they all seemed to be done by UK
establishments dealing with third world or US agriculture.


--
Jim Webster

"The pasture of stupidity is unwholesome to mankind"

'Abd-ar-Rahman b. Muhammad b. Khaldun al-Hadrami'

In article , Michael Percy wrote:
Phred wrote:

In article ,
"Jim Webster" wrote:
it did rather strike me that doing one for an area with five feet of
rain was something of a waste of time.

Each to his own of course, but I know of plenty of places around here
where farmers getting 80 to 100 inches of rain per year still find it
useful to irrigate at times to ensure optimum production of pawpaws,
bananas, and sugar cane.

In contrast the annual deficits would be minimal, guesstimate long term
averages about half an inch or less, for 5' precip areas of the british
isles (from which aspect of practical experience I believe the previous
poster is speaking)

Mind you, I must admit they probably don't decide when or how much by
using a water budget -- more likely kick the ground, look at the sky,
and say "Hmmm... better put on a couple of inches tomorrow." Much as
Gordon says above.

When/if weather data are available it would seem quite outdated not to use
them for waterbudget scheduling of serious irrigation.

Yeah. In fact the local Ag Dept provides at least an "evaporation"
service for broadcast over local radio stations in parallel with other
weather data. But this is really only intended for the irrigation
farmers in the district who get 30 to 40 inches of rain, and an
assured 8-month dry season.

Such are the rainfall gradiants around here, it's only 10 miles from
40 to 60 inch rainfall and *much* better distribution of the latter;
and another 10 miles or so to the 80 inch rainfall of the real "wet
tropics". I don't know of any equivalent evaporation service for
these wetter areas.

I might add that right at the moment a lot of the "wet" country is
actually drought stricken with dairy production down 30% and falling
and the usual "lush green pastures" would be a fire hazard if there
was any fuel left to burn! It's the driest year in over 80 years, or
even since local records began in many places around here.

The whole of eastern Oz is pretty much in the same boat, but the
contrast between "normal" times and the present conditions is more
obvious in places which are usually fairly wet all year every year.

Somewhat ironically, the obligate irrigation farmers here aren't
feeling the pinch as yet (the local dam still has a 12-month supply)
but many of the "opportunists" in the wetter parts who have been
relying on streams and aquifers for their supplementary irrigation
have been banned from pumping until things improve.


Cheers, Phred.

--
LID

Michael Percy wrote in message
...
Jim Webster wrote:

exactly, if you had a valid point you shouldn't need to sink to
making
personal attacks. I'm glad you have finally seen the error of your
ways.

I just hope you are not influenced by that.

so far little you have contributed to the discussion has been worth
considering never mind regarding it as influential


--
Jim Webster

"The pasture of stupidity is unwholesome to mankind"

'Abd-ar-Rahman b. Muhammad b. Khaldun al-Hadrami'



Mike

Michael Percy wrote in message
...
Jim Webster wrote:


Michael Percy wrote in message
...
Jim Webster wrote:

exactly, if you had a valid point you shouldn't need to sink to
making
personal attacks. I'm glad you have finally seen the error of
your
ways.

I just hope you are not influenced by that.

so far little you have contributed to the discussion has been worth
considering never mind regarding it as influential

Do you happen to regret it now?

no, If it hadn't been for this discussion I wouldn't have realised how
limited your contribution is.


--
Jim Webster

"The pasture of stupidity is unwholesome to mankind"

'Abd-ar-Rahman b. Muhammad b. Khaldun al-Hadrami'



Mike
--
On the eight day God installed Microsoft. On the ninth day he cursed
it.
That is how that goddamned operative system was created.