Our town encourages recycling of lawn clippings, leaves, brush and other yard waste. This material is then mixed and composted to a depth of 15 - 20'. It turned over periodically and when compost is finished 2+ years later, it is made available to residents free of charge. One can take as much as you can shovel. It is dark, crumbly, may contain twigs, and smells like topsoil harvested from an old forest floor.

My concern is the lawn clippings coming from lawns that have been treated with chemicals and if the chemicals breakdown during the composting process. I have listened to many far ranging opinions, use or do not use in vegetable gardens, use only on lawns or flower gardens.

I have purchased different brands of bagged compost that I was not pleased with the quality of composition of the compost. I have no idea what material was composted, how well it was composted and may contain higher levels of chemicals than the local free compost. It can be costly.

Your thoughts and suggestions for obtaining more information would be appreciated.

Yes, there are bound to be some contaminants, but grass dries down to a fairly small volume versus when it's wet, so in the entire mix any yard fertilizers or chemicals are probably pretty dilute. This sounds like a good option for local compost. The only way to have a "pure play" is to make your own, of course, but you probably can't produce the volume that you need that way.

Howard recommends zeolite as a product that tends to absorb some of the harmful chemicals used on lawns. You might want to mix some into the compost out of general principles, but I wouldn't worry about it.

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Northwesterner

Received this reply via an email that pretty much answered my inquiry

No one does testing on town composts because there is no consistency in the ingredients used. So the batch that you test in the spring will be different from that you have access to in the fall or the next year. Even if the same people dump grass and leaves from the same locations every time, the amount of possibly toxic materials will vary depending on when a product was put on a lawn and how soon afterwards the grass was cut. Add to that the variables of rainfall and irrigation and you can see the problem.

It's likely that because of the quantity of organic matter that gets incorporated in these composts that contaminants will be fairly dilute. No guarantees, however. My advice has always been that if you're using this compost keep it on shrubs, trees or lawns, not around edible plants, just to be safe.

You can amend your existing garden very nicely with chopped leaves - we do this annually by chopping them with a lawn mower. If you have space to put them in a pile after chopping you can let them sit without turning and the worms will start breaking them down quickly. The only thing I'd do to a pile such as this is to water it every two weeks in times of drought. For the fifteen years we lived in Osterville that's the method we used to make composted leaves. Now we chop them and add some directly into the garden and till them under in the fall. The remaining leaves get used in the veggie garden as mulch.

That's great advice about the leaves, and it is what I do here in North Texas also. My neighbors have the trees with all of the deciduous leaves, but they blow into my yard and the curb in front of the yard, so I plie them up, mow over them, and then put them in the garden.

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Northwesterner