Caliche
         Student Papers in Geology
Cochise College          

Geology Home Page                           

Roger Weller, geology instructor

wellerr@cochise.edu

by Casey Fuller
Physical Geology
Spring 2010             
 

     Caliche: Bane of the Desert Homeowner
 

            Have you ever tried to dig a hole through concrete? It is doubtful that you have. The
very idea is rather absurd. Really, who would try something that foolish? Surprisingly,
many people have tried, usually in vain, to dig through concrete. However, the material is
not called concrete: it is called caliche. Also known as hardpan, caliche is a naturally
occurring concrete found in arid environments, and inexplicably, in many frustrated
homeowners’ yards. But, what makes caliche so hard, what value does caliche posses, and
what can a person do to get rid of the nasty stuff? Caliche is a very interesting material
that can be hard to get rid of, but with the right tools and advice, anybody can stop
caliche from ruining his or her backyard garden plans.  


Illustration by Roger Weller

 

            As previously stated, caliche is a naturally occurring soil that is cemented by lime
(Weller). The creation of caliche is a fascinating process. Caliche is found in many
different varieties and places.


    
Photos of sand and calcite by Roger Weller
 

           Nevertheless, the basic ingredients that are needed to make caliche are the same.
Calcite (lime), gravel, clay, sand, and silt are the most common substances found in a
typical caliche, with lime being the constant ingredient (Caliche). These materials are the
content of every type of caliche, but the presence of these materials alone does not
create caliche. A very specific process must be completed before caliche is created.
 

            In order for caliche to form, several steps need to occur. The first step that must
happen is the leaching of the top layer of soil (Caliche). Leaching is the process where
mineral and organic materials filter down through the top layer of soil (the A Horizon).
The materials subsequently deposited in the next layer of soil (the B Horizon) are used in
the process of creating caliche (Leaching). Leaching is essential because it brings minerals
like lime do to the gravel, sand, and other types of materials that are not found in the A
Horizon. The lime then slowly starts growing crystals, which in turn merge with the
surrounding in many frustrated homeowners’ yards. But, what makes caliche so hard,
what value does caliche posses, and what can a person do to get rid of the nasty stuff?
Caliche is a very interesting material that can be hard to get rid of, but with the right
tools and advice, anybody can stop caliche from ruining his or her backyard garden plans.



The final form of caliche. Photo by Roger Weller
 

            There are two major uses for caliche. The first use is the harvesting of the caliche
for its lime content. Because caliche is an excellent source of lime, caliche is used to make
cement. It is rather interesting that this naturally occurring cement is used to make
synthetic cement. Besides being used to make cement, caliche has another economic
use. Caliche is used in the refining process of sugar. Again, this is because of the high lime
content in caliche. Even though caliche is not made exclusively of lime, it is cheaper to
refine the caliche, rather than purchase other sources of lime, such as limestone (Caliche).
Still, even though caliche does have some economic uses, what can a desert homeowner
do to get rid of caliche in his or her yard and garden?
 

            To any person who has dealt with caliche, the hardness of the material is fully
understood. Because of the difficulty in removing caliche, it is not recommended that a
gardener try to remove all of the caliche in the garden (Conquering). This is would be
very time consuming and difficult work.


Yes, caliche is that hard. Photo by Encefalus.com
 

            Unfortunately, there no magical ways of making caliche disappear or soft.
However, where there is a will, there is a way; there are some helpful hints are available
for the removal of caliche.

            The best way to get rid of caliche is to do it in a scientific manner. This means
that there should be a plan attack before ever picking up a pickaxe or crowbar. First,

one should decide how large of a hole needs to dug (Conquering). After the planning
stages are over, it is time to actually go and dig a hole. Depending on the depth of the
top layer soil, digging a hole can be easy or difficult. For example, if the top soil is deep,
then a gardener may only have to dig a chimney for drainage purposes. Digging a
chimney simply means that a small tube like hole needs to be dug through the caliche.
Placing the chimney close to the hole where the plant is will allow for proper drainage
around the plant (Carefree Gardener). However, if the top soil is shallow, then the only
option is to dig a hole into the caliche layer. It is very necessary to replace the caliche
with good gardening soil. Reusing the broken caliche for planting would not be good
for the plants (Conquering). While these steps may not be easy to accomplish, they are
the best way of efficiently removing caliche from a future garden.
 

            Caliche is a very interesting material. The process from which it is formed
demonstrates how unique this material is. It is also incredible how something so
seemingly useless could have economic value. However, caliche still is an enormous
irritant to any desert homeowner and gardener. The very thought of removing it can
be daunting. Nevertheless, the successful removal of caliche is still possible. Caliche is a
formidable opponent in the battle for the backyard, but with the right tools, gumption,
and energy, this fascinating, natural cement can be conquered by any desert homeowner.

 
Photo by Roger Weller
 

Works Cited

"Caliche." Wikipedia. Web. 20 Apr. 2010. http://www.wikipedia.org
 

"Caliche." The Carefree Gardener. The Carefree Gardener. Web. 21 Apr. 2010.
http://thecarefreegardener.tv/caliche.htm

"Conquering Home Yard Caliche." Master Gardener Manual. University of Arizona.
Web. 21 Apr. 2012. http://cals.arizona.edu/pubs/garden/mg/soils/caliche.html
 

"Leaching." Wikipedia. Web. 21 Apr. 2010. http://www.wikipedia.org
 

Weller, Roger. "Chapter 5." Http://skywalker.cochise.edu/wellerr/aawellerweb.htm.
Roger Weller, 5 Nov. 2009. Web. 20 Apr. 2010.
http://skywalker.cochise.edu/wellerr/GLGP-illvocab/GLGP-05.htm
 

Index of Photos Used

Opal’s Pals: http://skywalker.cochise.edu/wellerr/VGM/opals-pals/054.htm

Sand: http://skywalker.cochise.edu/wellerr/vrtglg/ha-maui/ripple3.htm

Calcite: http://skywalker.cochise.edu/wellerr/mineral/calcite/chalk1.htm

Caliche 1: http://skywalker.cochise.edu/wellerr/GLGP-pict/ch5/caliche1.htm

Atomic Explosion: http://encefalus.com/wp-content/uploads/2008/07/atomic_bomb_explosion.jpg

Caliche 2: http://skywalker.cochise.edu/wellerr/GLGP-pict/ch5/caliche2.htm
 

--------------------------------------------------------------------------------------------------------