I use that weed claw puller that grabs the taproot. It looks like a big undertaking at first, especially if there are a lot of dandelions or broadleaf weeds, but as with any weeding, the biggest effort is the first one. After that, it is some continuous maintenance to keep on top of any new weeds.

The yard looks much better afterwards. I would say that in your back yard, you can let it grow as you like. But in the front yard. people (whether it is the owner or the neighbors) are concerned with how the house looks, so you might have to give in there and work on the dandelions.

pick and wash dandelion, toss with olive oil, vinegar and salt, and eat. It is nutritious and a top remedy for sluggish liver.

http://www.scotts.ca/smg/goprod/scotts-ecosense-weed-b-gon-weed-control-selective-herbicide/prod10440002

Or dig them up and eat them.

Ecosense WeedBGon is a good leaf killer, but it kinda sucks at killing anything with a good root system or a taproot...even though they claim it works on them (which it technically does).

It's a bit underwhelming. It takes a good bit of product and/or multiple applications for established (or taproot) weeds.

It also can kill parts of your lawn even though they have commercials that claim it leaves it unharmed. The problem is the amount most people have to apply for results is enough to screw with the grass.

We don't have dandelions here, but the various other rosette-forming weeds are easy to kill. Slicing through the root about 1/2 inch below the rosette kills the plant because it only has the ability to resprout from the very top of the root.

The active ingredient in Ecosense Weed B Gone is Iron, an essential micro nutrient that becomes a poison in just over the necessary amounts plants need. Putting poisons in ones gardens or on ones lawn is contrary to good organic practice.

Yeah...pulling by hand is not an option here. The area is just too big, and there are too many. I've noticed that later in the summer when it gets hot and humid the dandelions really suffer. It's difficult to find a healthy leaf suitable for salad. Which is why I was inquiring about a biological approach. The product I mentioned in the original post called Sarritor uses Sclerotinia minor to infect and kill dandelions and other broadleaf plants. Unfortuneately it is not available in the U.S. as far as I know. Does anybody know of a source here? I know it gets mixed reviews, but the again so does Roundup.
I agree with Kimmsr on the toxicity of iron buildup, and we already have lots of iron in our soil.

http://www.cals.ncsu.edu/course/pp728/S_minor/Sclerotinia_minor.html

Sarritor is unlikely to be approved in the USA ... it's a plant pathogen that can really race through a warm field of peanuts or lettuce.

"The active ingredient in Ecosense Weed B Gone is Iron, an essential micro nutrient that becomes a poison in just over the necessary amounts plants need. Putting poisons in ones gardens or on ones lawn is contrary to good organic practice."

This is silly. Everything is a poison in the right dose. Even water.

Lazygardens, thanks for the link. You make a good point, I don't suppose Canadians grow a lot of peanuts.

JoppaRich, I don't think it's silly. I would reject using anything that would be required in such amounts to qualify as a poison...even water. Which, I guess in this case would mean turning my lawn into a lake to drown the dandelions.

Its possible to kill dandelions with two applications of 5% white vinegar, but there will be a small dead spot in the lawn that will grow back green in several months.

For a number of years, I have used a spring application of corn gluten meal plus hand digging for the rest of the season of the few sprouts with a claw type device (probably the same as described by gardenper).

"JoppaRich, I don't think it's silly. I would reject using anything that would be required in such amounts to qualify as a poison..."
Any substance you're using to kill something is by it's very nature, a poison. What your saying is inanity.

Don't kill them, eat them!

you can't eat them all the time. But when the season changes they help your metabolism and specially bile production. I usually make two large salads each in April and in October. I also make bitter alcohol infusions with them and other herbs, to drink year round.