Synthetic (specifically, vulcanized) rubber that’s used in tires does not “decompose”. There is no natural process for breaking it down into “base chemicals”. At best, a vulcanized rubber tire will self-shred into smaller pieces after 50-80 years, but there’s nothing that’s going to magically reverse the manufacturing process and turn the tire back into petroleum products (which, you might have noticed, don’t exactly degrade into anything either… since they’ve been around for a few million years underground).

As for plastics — it entirely depends on the type and where it’s stored. Thin polyethelene (think, grocery bags) will break down from UV radiation in a few weeks. If it’s exposed to it. Toss it in a landfill and bury it and it’ll be more like 10-20 years. Treat PE with UV resisting additives and it can last decades or centuries… which is what modern landfills are lined with. Polystyrene (think, styrofoam) will last much, much longer — hundreds or thousands of years. And, again, nothing munches on either of these, but UV light can eventually break the polymer chains. Oh, and there are virtually no recycling programs for polystyrene since it’s not cost effective to try and do so.

And yes, I’m all for recycling. My city has an excellent curbside recycling program, and an even more extensive recycling center <2 mi from my house. But recycling and “biodegradable” are not the same thing, and I think its you that needs to do some research in this area.

This isn’t “treehuggers and the media” engaging in some conspiracy; it’s basic science. I suggest you spend a little more time reading scientific research in peer-reviewed journals and a little less watching Fox News.

cl

What I am refering to is that even synthtic rubber, comes from base petroleum products that when broken donw, as they decompose they will return to base chemicals….

Don’t get me started on Plastics, too many people think that these are not biodegrable, some plastics are, and most can be recycled. but the media and tree huggers do a great job of showing us how bad they are, with little or no actual research

In any case — Yes, this is rather overpriced. You can get playground quality mulch (which requires more processing, and has far less steel wire in it) for ~$10/cu ft (yes, that’s still $270/sq yd, or about 10x the cost of natural mulch) or less. If you’re using it for landscaping, it’ll take quite awhile to pay back *AND* it won’t add any organics to the soil. If you’re using it for playgrounds, however, then it only requires about half as much for the same protection, so the cost proposition is better. (The big advantage being that, in theory, you don’t ever have to replace the mulch since it doesn’t decompose)

The zinc leeching is of questionable importance — most plants are not zinc sensitive and would have no issues growing in it. As for the runoff — it’s pretty much moot. If the rubber wasn’t shredded, then it’d be leeching from tire dumps anyway, so if this is a serious issue to you then campaign against the zinc content of synthetic rubber. Have fun.

Finally — I call BS on the “melting rubber”. If this was a serious concern, then it would’ve been seen decades ago in tire dumps, or even on cars parked on hot asphalt. The melting point for rubber mulch is over 200 degrees F, and the spontaneous ignition point is over 600 degrees F.

Note that the Ohio State paper mentions that they tested with “cigarette butts, matches, and a propane torch”. Cigarettes are not an ignition source for rubber mulch — they’re simply not hot enough. I’m unsure about matches. I’m sure you could ignite it with a propane torch, but that’s hardly a realistic scenario.

Here’s a report produced for the state of California on rubber mulch on playgrounds and other surfaces; note that it doesn’t address the ignition issue, but it does cover the toxicity issues extensively. http://www.ciwmb.ca.gov/Publications/default.asp?pubid=1206

Haa haa haa Sounds like some of you also believe all the articles in the New York Times………..

If it is processed properly, cleaned and prepped and you watch the PH i your soils you will many years of great service, and in fact it it very effective

cl

Most mulch packaging recommends it be applied to a depth of about four inches, IIRC, which means one cubic yard of mulch would cover nine square yards (81 square feet) of surface area at that depth.

cl

August 27th, 2008 at 1:04 pm
I’d think twice before I put rubber mulch down in my yard. Then, if I decided to go ahead and do it, I’d think again.

Rubber mulch bleeds zinc and cadmium, is not as effective as organic mulch in controlling weeds and eventally DOES decompose into components that are particularly toxic to beneficial landscape microbes and aquatic environments. It’s also flammable (as organic mulch can be) and difficult to extenguish

Where is this data coming from?

Sorry, I do not get your math. Are you saying that it will cost $405 to cover one square yard when you pile on the mulch to a height of 1 yard? If you pile on the mulch to a height of 1 feet (still too much height, I think), it will cost you 9 cubic feet times $15 = $135.

Or are you just saying that one cubic yard of this mulch is $405? This point, I get.

The fact that this stuff costs more than about a buck per cubic yard seriously bothers me, though, because the companies that recycle old tires are getting paid to dispose of them in the first place.

cl

ADA = Americans with Disabilities Act
http://www.ada.gov/

ADA is what the site says… I might be the American Dental Association, think of all the chipped, broken, and lost teeth that happen on the playground.

rbb:

Like I said I can’t understand why all the new recycled materials are so much more expensive then comparable materials. It’s not like you have to go milk the trees to get the rubber, it’s coming to your factory in big donut shaped chunks of rubber, all you need to do is grind the thinks up and remove the metal from the radials… maybe dye it to look pretty.

Composite decking is the same way, its sawdust and recycled plastic bags, they just grind it up and glue it together… but they charge more than endangered Rainforest wood species.

We pay through the nose to recycle, then we pay through the nose again when we buy recycled products. Seems to me that somebody is profiting from the “Green” revolution.

As in the American Dental Association?

http://en.wikipedia.org/wiki/Osborne_Reef
http://wdfw.wa.gov/do/newreal/release.php?id=aug1808a

Er, maybe not.

It took 20-30 years to understand why tire reefs would be problematic, and another 20-30 to clean them up (I’m guessing, since it’s not finished yet). We may not know the problems of used tire mulch for another 20-30 years, but I’m betting that the “permanent” feature will become a curse at some point…

Rubber mulch bleeds zinc and cadmium, is not as effective as organic mulch in controlling weeds and eventally DOES decompose into components that are particularly toxic to beneficial landscape microbes and aquatic environments. It’s also flammable (as organic mulch can be) and difficult to extenguish

http://www.puyallup.wsu.edu/~Linda%20Chalker-Scott/Horticultural%20Myths_files/index.html

http://www.ohio4h.org/~news/story.php?id=2865

http://www.sare.org/sanet-mg/archives/html-home/18-html/0259.html

The top two links referenced are to the Washington and Ohio state Extension services and the third is to an Agronomist with the USDA Agricultural Research Service.