Its not just rubber, but contains what ever chemicals they use to make tires. I've seen of these kinds of products deteriorate and crumble in sun light, but that takes years.

Personally, I wouldn't want the stuff because I don't know what all is in it, and probably the easiest way to improve a soil is to add an organic mulch like bark and let it decompose.

Rubber mulch is just a way to make the next owner have to hassle through the process to remove it later (or you, if you live there long enough).
It is just like using gravel over weed barrier. In the big picture, a very short term solution. A good, thick layer of rubber, or gravel, over weed barrier only slows the build-up of debris (leaf particles, dust, etc.) down at the base on top of the barrier; later upon which weeds and other plants begin to germinate and defeat the purpose of the rubber or gravel...
WOOD mulches build the soil over time, albeit you have to keep replacing them because they biodegrade. However, a good, thick 3-1/2" mulch when replaced will accomplish the goal of limiting weeds. If you have weeds showing up in your mulch, it is time for more mulch. To me, the labor involved in removing rubber mulch or gravel in a few years is much greater than the labor involved in spreading fresh, new mulch that looks so good, year after year.
hortster

It doesn't last for "years to come". Leaves and dirt infiltrate the mulch and weeds start growing.

Good grief! The most exciting thing about mulching is feeding your soil with it, attracting worms, improving things. I can't believe anyone would seriously consider covering their yard with rubber.

That's just me.

Ditto the comments above. I might (and, then again, might not) be willing to use rubber matting or mulch for a playground survace but not for anything else. Wood chips will last a few years and you can just add more as needed. Wood chips over paper or cardboard is even better for weed suppression than wood chips alone.

I've seen labels for this stuff that says not to use for plant beds, trees, gardens. It also stinks to high heaven!

The shredded tire mulches add nothing of value to soil and are known to add heavy metals such as Zinc, Cadmium, Lead stuff most people would not like in their soil. Articles in previous issues of Fine Gardening and Organic Gardening magazines both strongly advised against using this stuff.

Another thing to consider is allergy. No kidding. I have an anaphylactic-level allergy to natural rubber latex. Schools have to go to great efforts about peanut allergies, but latex allergy is 5-10 times more common than peanut allergy in the general population.

Some types of latex are more problematic. It hasn't been conclusively determined, but they seem to shed particles that coat nearby surfaces. The kind of stuff in these rubber mulches must be like that, because I start to get a mild, early reaction if I just walk by the stuff at a garden center. I hate it that they've started marketing the stuff.

If we ever move, we wouldn't be able to buy a house where latex mulch was *ever* used, because of the way that it breaks down. And my allergy has just barely progressed to anaphylaxis - lots of people have it worse than me.

Obviously, it's personal for me, but I figure it just plain doesn't make sense to use something this problematic for even 1% of the general population. (Though incidence might be as high as 6% - they can't decide.) And as others have said, the alternatives aren't just comparable - they are better.

You literally cannot extinguish tire fires.

Think about that, in relation to your home.

Yep--I'm the unlucky new owner of a house with rubber mulch. (the rest of the house is great, don't get me wrong.)

The realtor told me it was to prevent termites. It also prevents crickets, who sing beautifully at night. I'm about to start removing it. What about the weed barrier fabric underneath? Under that is dead, clayey soil. Can anyone advise me? Should I leave about 1 ft of it right around the house foundation to stop those termites?

The stench from rubber mulches on a hot summer day would keep me from using it and would prompt me to get rid of all of it there was as quickly as possible. What you found under the landscape fabric is typical of what I have seen under tire piles, a compacted soil with no life.
You can however renew that soil, eventually, by adding a good mulch material that will add organic matter to the soil. Does that soil also have a putrid odor to it?

At first glance rubber mulch sounded ideal but then the questions began to arise. All of these posts mention things that I have often wondered about rubber mulch. I would think that the public would demand that the rubber be cleansed, neutralized, odor free, etc. Think I will check into this further, I can't imagine taking old tires and chewing them up, bagging and sending of to a big box store. I'm not in the market for rubber mulch but I'm interested enough to do the work of researching the subject as it is a troubling one.

The following info is from the description of the rubber mulch sold by Costco. There was one review from a customer who had just put this product down about 2 weeks ago. He loved it. Said it looked great. Now whether all rubber mulch is processed the same as the Rubberific brand, is another question and due more research.

Rubberific Mulch stands alone as the industry�s hallmark recycled rubber mulch. This realistically-textured groundcover is made from 100% recycled rubber and will not fade, rot, compress or lose its original beauty, even after years of exposure to the elements. Rubberific Mulch saves homeowners time and money, and is one of the safest playground coverings available.

Color: Redwood
80 cubic feet (640 square feet at a depth of 1 � inches)
Made from environmentally-friendly materials approved by the EPA
Preserves ground moisture without absorption, helping to keep plants healthy
99.9% wire free
Easy to install
Long-lasting color
Little to no annual maintenance
Does not attract termites, carpenter ants or other harmful insects
Five times heavier than wood mulches
Inhibits growth of molds and fungi, reducing allergy risk
Minimizes dust
ADA-approved material for playground use
Exceeds U.S. Consumer Product Safety Commission standards for playgrounds
Made in USA

Keep in mind that the manufacturer of a product is not going to list the real hazards of the product they sell.
Rubber mulch contributes nothing worthwhile to the soil it covers.
Rubber mulches will contribute heavy metal contamination to the soil they cover.
Rubber mulches do not attract any insects because it is a dead material with nothing for them to eat.
Rubber mulches will require that synthetic fertilizers be used to feed the plants growing in that soil since that material will not provide any nutrients as other materials will do.
Rubber mulches have no place in an organic garden.

It is possible there are some applications for rubber mulch, but in general I think it's a liability in the landscape. Not only is it non-organic, but what if you want to get rid of the stuff, or maybe a subsequent owner of a property wants to get rid of it?

Ditto on the landscape fabric. Organic debris accumulates, weeds take over, and you're stuck with trying to extract the weeds, plants, and landscape fabric.

Woodswalker, ideally I would not have any mulch, landscape fabric, organic debris, vegetation, or piles of stuff near the foundation of your house. These encourage insects and rodents. Gutters and grading should effectively move water away from the foundation. A scuffle or stirrup hoe makes short work of weeding in bare soil.

"environmentally friendly" because it keeps nasty, old, stinky tires out of the landfills, lolol

Does anyone have a link to data showing test results for heavy metal content or other toxins in rubber mulch? I have always wanted to see some actual numbers but have not come across any yet.

There is a discussion of rubber mulch at: Guest Rant: Rubber Mulch: I've been Converted

When I was still on the Fire Department we would be called out to stand be as a hazardous materials personnel when a tire dump was found and clean up of that dump was underway. Back then I had a chart that listed the levels of lead, cadmium, and several other heavy metals the had been found in soils under other rubber tire dumps and those cleaning up the dumps would excavate a large amount of soil that was under the tires. That list of heavy metals was from the USEPA, but today finding that list is immpossible since someone found they could make a lot of money shredding those tires and selling them as mulch.
It is kind of like the Artificial Turf business, which also uses shredded tires. There are indications that children playing on Artificial Turf have elevated levels of carcinogens afterwards which are poo pooed by the industry poo pooes.

"EPA does not consider scrap tires a hazardous waste."

Years ago the USEPA considered these used tires a hazardous material and listed all kinds of heavy metals they could leach into the environment. However, since someone found that this waste material could be ground up and sold as "mulch" those concerns have gone away. This article, written by Dr. Linda Chalker-Smith might be of interest to some.

Here is a link that might be useful: Rubber Mulches

There are grades of 'hazardous' and the terms are often misused.

Hazardous Waste is a particular term with very precise definitions, and tires would certainly not be in that category as suggested by pt03's post above. Hazardous Wsates have very stringent handling and disposal regulations.

'Hazardous Material' is a term applied more in the emergency response field, in terms of flammability, toxicity, reactivity, etc. when fighting fires or responding to spill incidents. I would say tires are a haz mat only in the sense that when they catch on fire, you definitely have serious air and runoff problems.

kimmsr's link says:

"It's toxic: Research has shown that rubber leachate from car tires can kill entire aquatic communities of algae, zooplankton, snails, and fish. While part of this toxicity may be from the heavy metals (like chromium and zinc) found in tires, it's also from the chemicals used in making tires. These include 2-mercaptobenzothiazole and polyaromatic hydrocarbons, both known to be hazardous to human and environmental health."

Algae and zooplankton? OK, don't mulch the bay with it. ??

I would still like to see the 'research.' The article presents no data or references. I am not arguing the point about metals, because I DON'T HAVE ANY DATA. The idea that someone supressed data when they decided tires could be sold as mulch is disingenuous. How about the formulas were changed to reduce or eliminate metals in tire production? How long ago was this?

I do have concerns about the PAHs, and that's the first I've heard of 2-MBT but it makes sense as it's a rubber vulcanizing agent (as well as a fungicide - and possibly a dessert topping? If you remember the old Shimmer commercial on SNL) Had a site with 2-MBT once. Its toxicity was so low there were no federal numbers for safe levels in soil, though.

Again, I am no fan of rubber mulch, I just want the risks to be properly expressed.

Here's a study conducted by CO State Univ. that looked at metals in soil after sitting under rubber mulch for about 5 years.

"Total and plant available Zn, As, Cd, Pd and Ni were examined for each treatment. The total and plant available Zinc levels in the rubber mulch treatment were 21.2 and 19.0 parts per million (ppm) as compared to a range of 5.6 to 6.8 ppm respectively for the other treatments. The total and available levels of As, Cd, Pb and Ni were similar for all treatments."

http://www.coopext.colostate.edu/TRA/PLANTS/heavy_metals.shtml

It appears this study found no significant changes in metal concentrations in the soil. Still doesn't tell me what's in the rubber itself, but a useful piece of info nevertheless.
I will keep searching around.

This EPA page,

http://www.epa.gov/nerl/features/tire_crumbs.html

has a link to a study conducted by EPA in 2008 where they actually sampled rubber mulch. Note how hidden and suppressed this is - I found it in 5 minutes.

EPA points out the study did not collect a massive number of samples, but:

Ranges for playground crumb rubber samples:

Pb 1 to 8 ppm
Zn 4300 - 18,000 ppm
Cr 0.3 - 3 ppm

Pb is very low here, well within the range of soil background levels in many areas, including mine, and is even farther below what EPA considers safe for soil at a residence (400).

Zn sounds high, but it is not nearly as toxic as lead. Our state has a safe level for residential use of 22,000, and the high end of the range is below that.

Those Cr values are quite low and would present no significant toxicity.

So, it's not too different from soil, really, with the possible exception of zinc. I wouldn't recommend eating it, any more than you would soil.

It's a long report and I didn't see whether they tested for any other metals, but I suspect not. I still don't have quantitative numbers on solvents, vulcanizers, etc. Will keep looking.

I still don't like the stuff for so many other reasons.

This from the EPA fact sheet on this study - they admit it's limited. It was originally done in response to high Pb found in some rubber mulch in NJ. Obviously it wasn't reproduced here.

"As part of this evaluation, data were collected at a limited number of sites. The full study protocol was implemented at two synthetic turf fields and one playground. Additional samples were collected at four other synthetic turf fields and a second playground. Sampling sites were located in North Carolina, Georgia, Ohio, and Maryland.

On average, the concentrations of components monitored in this study were below levels of concern; however, given the very limited nature of this study (i.e., limited number of components monitored, samples sites, and samples taken at each site) and the wide diversity of tire crumb material, it is not possible to extend the results beyond the four study sites or to reach any more comprehensive conclusions without the consideration of additional data."

Common sense would reveal that millions and millions of pounds of material are worn off tires every year in Canada and the U.S. We probably inhale a lot of this 'dust' over the years.

I've never used rubber mulch but I won't get bent out of shape because someone wants to.

Lloyd

Coal is a naturally occuring material that could be used as mulch. Would you? How about the ash residue from burning coal?
Have you looked at some of the studies about Artificial Turf?

No, I would not, any more than I would use rubber. I hope you understand I am not advocating its use. Just objectively sharing and reviewing data to understand the human and environmental risks.

As I've said, there are a bunch of other reasons I don't like the idea. I just haven't identified a serious health risk based on the limited data I've looked at so far. I feel it's my duty to do that analysis since I know something about it.

The EPA study did look at artificial turf, which I was surprised to learn also has a tire base. I didn't look too closely at those numbers since it was not the topic. I think some of them were higher.

Speaking of coal, actually I prefer burning crumb rubber in power plants along with coal. Gets rid of the darn stuff, solving the landfill problem, and helps our energy production. They do it right here at the university power plant in my city.