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As I'm sure you're aware, glyphosate is usually only appropriate as a weed killer on your property if you're looking to kill all vegetation in/around where you spray it. For example if you wanted to "nuke" your lawn by killing all the grass and starting over with new grass. It's a non-selective herbicide in this context, it kills everything.

If you've got some dandelions or thistle, and it's not out of control, the nice safe way is to pull them up by hand or, if they're between pavement cracks, pour boiling water on them.

Broadleaf weeds growing in your lawn that aren't easily hand-pulled can be killed with a selective herbicide like 2,4-d. Tough underground vine-style weeds like creeping charlie or wild violet will need a selective called triclopyr. Crabgrass is best killed by a selective called quinclorac. Yellow nutsedge requires a selective called sulfrentrazone or another called halosulfuron.

Selectively kill the weed infestations as best you can, get rid of the bad ones before they go to seed, and focus on the health of your grass -- in most parts of your lawn, healthy grass will out-compete weeds.





Don't spray herbicides everywhere (unless you're certain that's what you want or need).

Instead, just spray each weed a little bit, right above where the leaves connect to the stem.


Glyphosate is extremely effective as a targeted weed killer. It only impact what you spray it with. It does not teleport from one plant to another. It's also not strong enough to kill heathy mature plants with a small amount of overspray.

I get a little paintbrush and paint the leaves of each dandelion with round-up - that ends up killing them but largely leaving other plants alone.

I learned to appreciate the dandelions.

How is this easier than pulling the plant out of the soil?

Dandelions are really, really hard to eradicate by pulling. The roots grow very deep, and if you don't get them completely, the plant can re-grow from what's left.

Even if you do successfully get it out, it really is going to be more work than painting a weed killer on them.


My dad use to have my brother and I work for hours during the summer pulling dandelions in the lawn (to be fair he was out there with us doing it himself also). We each had a knife with about a 4" long blade, we would cut the root as deep as we could and pull the top out. Never really seemed to reduce the number we had.

It depends on the target and the surrounding soil. It’s often easier to pull especially for the random weed that sprouts up around your landscaping. However if you are trying to manage an infestation of invasive species, where the surrounding soil will have a seed bank heavily contaminated with seeds from the years of invasive reproduction, it’s usually a bad idea to merely pull. You can expose soil to sunlight and cause an explosion of dormant seeds. And some nasty invasives are nearly impossible to remove by hand because of their root structure — some species even leave little rhizomes broken off in the soil along the root structure when you pull off the foliage causing a hydra effect.

tl;dr targeted herbicide is a much less evolutionarily selected-for offense, as opposed to hand cultivation which mimics attacks plants have evolved to survive for eons


I did much the same, but with a hypodermic syringe, on knotweed many years ago.

Yours is so much more.. tender though. Poor dandelions, but at least you made it personal!


When I really want to nuke it so that nothing grows, like in a decorative stone area, I use water softener salt. I dissolve it in a bucket of water until no more will dissolve then pour it wherever I want the vegetation to stop growing.

Anything there will die, and nothing will grow again for a long time. Although, it does spring back to life eventually. Usually once a year is sufficient.


> As I'm sure you're aware, glyphosate is usually only appropriate as a weed killer on your property if you're looking to kill all vegetation in/around where you spray it.

> It's a non-selective herbicide in this context, it kills everything.

It is a non-selective herbicide, but it's not a systemic herbicide. It functions by interfering with photosynthesis, but since it is minimally absorbed via root systems, it must be applied directly to the foilage. You can spray it on the ground around a plant and that plant will happily ignore it. This is why the instructions are explicit about applying directly to the foilage during sunny days when the wind is light.

As a homeowner, I loved glyphosate. It was cheap, simple, effective, and could be applied in a selective manner. It's not the best choice for getting rid of broadleaf weeds in a lawn, but I used it all the time in my gardens to kill weeds and keep the bermudagrasses out.


Roundup makes a product that looks like roll on deodorant. You literally roll it onto the leaves of the things you want to kill, and everything else remains unharmed.

I'm also a fan of glyphosphate. Nothing else works nearly as well. People who are critical of "chemicals" to control weeds have never had to deal with a weedy pavement before.


Yes! I also used glyphosate to kill things growing in and around my sidewalk, driveway, steps, and curb. I've also used a propane torch for the same purposes, but it requires more effort and cannot be applied quite so selectively. It works, though, and is a good choice for anyone who would rather use a petroleum product than an herbicide.

I looked up the product you mentioned and you're right -- it does look like deodorant! It's a gel that contains glyphosate and isopropylamine salt. Neat!


Carbon Robotics sells a weed burner that works via a laser, if you’re dead set against both petrochemicals and glyphosate.

Sadly: no consumer model yet.


Normal propane weed burners work pretty well against weeds in areas where it's reasonable to use something like that. But they aren't good if there's anything nearby you want to protect.

Hey, I really like the idea! There are various palm trees around here, I keep fighting the unwelcome guests that show up. Unless caught really early they are basically impossible to pull and almost all of them show up in places I don't want to dig them out. A contact-only killer sounds like just the right thing.

Can anyone confirm that "pour boiling water on them" is as good as deadly chemicals ? :)



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