Urine sterilizes soil, how?

RSmith chem at ns.sympatico.ca
Wed Jun 24 12:26:31 EST 1998

My background is in chemistry.

I would like determine means by which canine urine kills lawn flora and
sterilizes the soil. This post is not my first attempt to sort this out,
agricultural specialists, vets, a plant physiologist, have all expressed
interest and offered various musings into the phenomina , but no
explanations for what i have observed.

For one year we have had a 'new' dog on a different dog food [two
parameter changes, our previous dogs never illicited this problem]. 
This spring we noticed that the lawn was dead under the when the
snow/ice patches he urinated on were melted. None of the four attempts
at reseeding were successful; surface reseeding prior to and after
fertilizing and appl~ of lime, reseeding with soil cover, 4 inch soil
turnover with reseeding.
I had to dig up 4 inches of the soil and replace it before the new grass
His urine continues to kill the grass so it is not a 'winter kill'
The two most curious aspects of this is the way the vegitation dies and
the fact that it is a lasting effect. If i don't wash the urine away
fairly quickly, I will notice a slight yellowing/browning of the grass
and a dark-almost black- discoloration of broadleaf weeds and moss in
about a week or so. Once the initial signs appear I cannot intervene by
repeated rinsing, i might as well dig it upon the first sign. 
The soil i dug up had a very strong ammonia/urea smell to it but i
thought it may have been the commercial fertalizer i used on those spots
in an attempt to rejuvenate them.

I have had a std urinalysis on the dogs urine and the pH is normal (near
neutral) and there is no excess protein.

At the same time we got the dog we switched to a premium dog food (
Purina Pro), but the customer support person claims that this is not
food related. 

The plant physiologist was most interested in the fact that the dead
soil will not even allow the grass seed to germinate. He recalled that
corn glutin will have the same anti-geminating effect on some seeds.

-it is the acidity of the urine which is the problem, and lime will
correct it. It did not, but i only applied it once.
-It is 'NITROGEN BURNING' from the urea/ammonia in the urine.  Rinsing
(diluting) should  prevent the germination inhibiting action.
- leave it alone and it will return. Not in two months or more of warm
weather with natural and hose watering.

Landscaping has exposed both damp clay-soil and sandy well drained soil.
It is the damp clay soil which suffers the most.
We are directly downslope from a mixed deciduous/conifer forest with
moderate subsurface aquifer.

Any thoughts, suggestions, answers, mechanisms, interventions, ...spare
car keys?
Rick, Canada

More information about the Plantbio mailing list