Week of 07/11/10

Dear EarthTalk: Within my lawn I have over 100 citrus, mango and avocado trees. When I use Scott’s Bonus S Weed and Feed, am I feeding my new fruit any poison? Will the weed killer be taken up by the fruit?

—Richard Weissman, Miami, FL

In short, yes and yes: You will jeopardize the health of your fruit trees and your yard in general if you use such products. Scott’s Bonus S Weed and Feed, as well as many other "weed-and-feed" fertilizers (Vigero, Sam"s, etc.), contain the harsh chemical herbicide atrazine, which excels at terminating fast-growing weeds like dandelions and crabgrass but can also kill other desirable plants and trees and damage your entire yard as toxin-carrying root systems stretch underground in every corner and beyond.

Howard Garrett, a landscape architect who founded the DirtDoctor.com website and is an evangelist for natural organic gardening and landscaping, points out that anyone who reads the label on such products will learn that even manufacturers don’t take their health and environmental effects lightly. Some of the warnings right there in black and white on the Scott’s Bonus S Weed and Feed packaging include precautions against using it "under trees, shrubs, bedding plants or garden plants" or in the general vicinity of any such plants" branch spreads or root zones.

Scott’s also recommends not applying it by hand or with hand-held rotary devices or applying "in a way that will contact any person either directly or through drift." And just in case you were thinking it was okay for the environment, Scott’s adds that "runoff and drift from treated areas may be hazardous to aquatic organisms in neighboring areas" and that the product is "toxic to aquatic invertebrates."

Howard Garrett, founder of the Dirt Doctor website, recommends sticking to organic fertilizers — which contain naturally buffered blends of major nutrients, trace minerals, organic matter and carbon — for the well being of plants, humans and animals alike.© The Dirt Doctor

Of course, homeowners aren’t the only ones who want lush plant or grass growth without weeds. Farmers have been using atrazine for decades all over the country, although not surprisingly concentrations are highest along the Midwest’s so-called Corn Belt. The herbicide consistently delivers slightly increased agricultural yields, but environmentalists wonder at what cost. The Natural Resources Defense Council (NRDC), a leading environmental research and advocacy non-profit, reports that atrazine exposure has been shown to impair the reproductive systems of amphibians and mammals, and has been linked to cancer in both laboratory animals and humans. Male frogs exposed to minute doses of the herbicide can develop female sex characteristics, including hermaphroditism and the presence of eggs in the testes. Researchers believe such effects are amplified when atrazine and other chemicals are used together.

As to safer alternatives, Garrett recommends organic fertilizers. "Synthetic fertilizers are unbalanced, often contain contaminants, have no carbon energy, contain far too much nitrogen and have few trace minerals," he says. "Organic fertilizers, on the other hand, contain naturally buffered blends of major nutrients, trace minerals, organic matter and carbon. They have lots of beneficial life and, most important, they contain nothing that will damage the roots of your trees and other plants." Some of Garret’s top choices include corn gluten meal (a natural way to prevent the growth of new weeds), THRIVE by AlphaBio, Garrett Juice, Ladybug, Medina, and Soil Mender. More and more choices are coming on the market all the time thanks to the growing popularity of organic gardening.

CONTACTS: Scotts; The Dirt Doctor; NRDC.

Dear EarthTalk: Where do you recycle plastic stuff like sandwich bags, Saran wrap and plastic grocery store wrappers? Can they just go in with other plastics in the recycling bin? There never seems to be any information available about this.

—Renee La-Fountaine, Lake Hughes, CA

Clinging plastic like Saran wrap is difficult to recycle because the resin it contains that gives it wrapping power cannot be extracted without massive amounts of energy -­ more than it would take to make it new from scratch. And given that it"s usually soiled with some kind of food, used plastic wrap should always just go right into the trash. Pictured: A 1961 magazine ad for Handi-Wrap.© Pink Ponk Studios, courtesy Flickr

The reason you don’t hear much about recycling these types of plastic films is that most municipalities don’t take back items intended to wrap food. One exception may be sandwich bags, which are made from easy-to-recycle polyethylene, as long as any hard (i.e. "Ziploc") components are removed and they are rinsed free of any food debris or stains.

For that matter, if you are going to the trouble to wash them, you may as well dry and reuse them at home a few times before relegating them to the recycling bin. There are even small countertop racks available for hanging plastic bags to dry before reusing them.

Clinging plastic like Saran wrap is problematic for recyclers because the resin that it contains (to give it wrapping power) cannot be re-extracted without massive amounts of energy—more than it takes to make it new from scratch. And given that it’s usually soiled with some kind of food, used plastic wrap should always just go right into the trash.

Other non-recyclable plastic films include dark-colored plastic bags, bags with handles or drawstrings, and anything else designed to be wrapped around food. Since you can’t even rinse or recycle these kinds of plastics, it’s better to avoid them altogether and invest in some reusable containers to store leftovers.

Another option is to use plastic grocery store shopping bags (though they are increasingly being phased out) to wrap your food leftovers in. Many municipalities and most stores that provide such bags accept them for recycling, so once you’re done with them they can be recycled or returned to the store, after which they can be melted down and incorporated into weather- and rot-resistant window and door frames, decking (such as Trex), palettes, pipes and other long-lasting hard goods. Like with sandwich and other bags you intend to recycle, make sure plastic grocery bags are clean before you turn them in for recycling.

If you are a Ziploc bag or plastic wrap fanatic but want to do the right thing by the environment, look for plastic food storage film or bags made from biodegradable polymers. Some popular brand names to keep an eye out for at Whole Foods and elsewhere are Eco Wrap, EcoFlex and BioBag. These plastics—some of which are made from agricultural scraps left over from corn crops—can go right in with yard waste or other compostables and will break down over time accordingly just like cardboard or food scraps. With time major brands will undoubtedly be offering similar products.

But even though there may in fact be "greener" plastic out there, reducing our reliance on disposable bags altogether should be the ultimate goal. Luckily many grocery chains are hip to greening their own operations and image, and are giving away or selling for a nominal amount reusable canvas shopping bags so customers don’t have to choose between wasting plastic and paper at the checkout line.

CONTACTS: PlasticBagRecycling.org; Trex; BioBag.

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