# Garden work - Weeds in walkway cracks **URL:** \ **Category:** Factual Questions\ **Created:** [June 2, 2009, 10:57pm UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517 "2009-06-02T22:57:30Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Casserole](https://avatars.discourse-cdn.com/v4/letter/c/b77776/32.png) [@Casserole](https://boards.straightdope.com/u/Casserole)\ **Post date:** [June 2, 2009, 10:57pm UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/1 "2009-06-02T22:57:30Z")
Hello dopers! Just did some spring cleaning today, in and out of the house, and came upon some weeds (read that as “a lot” of weeds) in cracks all over the walkway leading to the house, and along the side. Now, for some reason or another, pesticides are banned in Ontario, so RoundUp is out of the question. I feel as though there ought to be a better solution than getting down on my hands and knees with a chisel and hacking the things out from between the stones… Any ideas? (Pictures to follow.) ---
**Author:** ![old\_joe](https://avatars.discourse-cdn.com/v4/letter/o/58956e/32.png) [@old\_joe](https://boards.straightdope.com/u/old_joe)\ **Post date:** [June 2, 2009, 11:04pm UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/2 "2009-06-02T23:04:11Z")
My backyard is covered in pavers, no grass at all and I use a tiger torch to weed them. You dont burn them you just need to singe them, that destroys the leaves. Works great. I think lee valley sells em. beats the heck outa hands and knees… ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [June 2, 2009, 11:06pm UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/3 "2009-06-02T23:06:03Z")
Boiling water. Leaves no nasty residue. ---
**Author:** ![racer72](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/racer72/32/3075_2.png) [@racer72](https://boards.straightdope.com/u/racer72)\ **Post date:** [June 2, 2009, 11:21pm UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/4 "2009-06-02T23:21:28Z")
> [@Casserole](#): > > Hello dopers! > Now, for some reason or another, **pesticides** are banned in Ontario, so RoundUp is out of the question. (Pictures to follow.) Herbicide. Pesticides kill bugs. Vinegar works too. Makes your yard smell like a salad. ---
**Author:** ![Casserole](https://avatars.discourse-cdn.com/v4/letter/c/b77776/32.png) [@Casserole](https://boards.straightdope.com/u/Casserole)\ **Post date:** [June 2, 2009, 11:34pm UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/5 "2009-06-02T23:34:39Z")
My bad, I meant herbicide 🙂 I’ll give the boiling water a shot, thanks **DrDeth**! Vinegar’s also an interesting solution… nice and cheap, and I could sprinkle some on my fries once I’m done. ---
**Author:** ![levdrakon](https://avatars.discourse-cdn.com/v4/letter/l/49beb7/32.png) [@levdrakon](https://boards.straightdope.com/u/levdrakon)\ **Post date:** [June 2, 2009, 11:48pm UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/6 "2009-06-02T23:48:22Z")
I’ve heard full strength bleach, but I tried it on some grass and it didn’t do much. I’ve also heard of using gin. I think the juniper berry is what does it. Pure fertilizer can kill your lawn grass pretty well dead if you spill a bunch in one spot. Plants don’t like salt much either. ---
**Author:** ![Dallas\_Jones](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dallas_jones/32/3277_2.png) [@Dallas\_Jones](https://boards.straightdope.com/u/Dallas_Jones)\ **Post date:** [June 3, 2009, 12:33am UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/7 "2009-06-03T00:33:29Z")
Really? Round Up is banned? All it does is shut down an enzyme in the plant that is needed for growth, it isn’t poison. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [June 3, 2009, 12:44am UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/8 "2009-06-03T00:44:41Z")
> [@](#): > > All it does is shut down an enzyme in the plant that is needed for growth, it isn’t poison. So how would you describe shutting down an enzyme needed for growth, if _not_ poison? ---
**Author:** ![Flutterby](https://avatars.discourse-cdn.com/v4/letter/f/6f9a4e/32.png) [@Flutterby](https://boards.straightdope.com/u/Flutterby)\ **Post date:** [June 3, 2009, 12:50am UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/9 "2009-06-03T00:50:01Z")
We use boiling water also, I’ve found it works wonderfully for the weeds and the grass that grows up there. Now I just need to find a way to kill all the weeds on the lawn itself without digging up three quarters of the yard (okay, maybe only half). I’m not sure if herbicides are banned yet here, but I can’t seem to find them so I’m guessing so. I have a child though, who loves to play on the grass, so I’m leery about using them anyway. ---
**Author:** ![Blake](https://avatars.discourse-cdn.com/v4/letter/b/a9a28c/32.png) [@Blake](https://boards.straightdope.com/u/Blake)\ **Post date:** [June 3, 2009, 1:06am UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/10 "2009-06-03T01:06:55Z")
> [@racer72](#): > > Herbicide. Pesticides kill bugs. No, no and no. Herbicides are a type of pesticide so it is perfectly correct to [refer](http://www.epa.gov/EPA-PEST/2007/May/Day-02/p8000.htm) to [Roundup](http://books.google.com.au/books?id=wGbV-OjApeMC&pg=PA273&lpg=PA273&dq) as a [pesticide](http://www.inchem.org/documents/pds/pds/pest91_e.htm) Bugs are a specific type of sucking insect. The vast majority of pesticides are not designed to kill bugs. I assume you mean insecticide rather than pesticide, but even if we restrict ourselves to insecticides, the vast majority are designed to killed flies, cockroaches, caterpillars and so forth, rather than bugs. Pesticides kill pests, not bugs, and in addition to herbicides the term encompasses acaricides, rodenticides and so forth. None of which target bugs. > [@Casserole](#): > > My bad, I meant herbicide 🙂 You’re good. You meant pesticide and that usage is perfectly correct scientifically and linguistically. It’s the usage used by the EPA and WHO when referring to glyphosate (Roundup). My local hardware store sells Roundup in the section marked “Pestcides and fertilisers” and I’m failry sure it’s not a fertiliser. IOW it not only scientifically accurate usage it’s also the the common usage of the man in the street. ---
**Author:** ![Blake](https://avatars.discourse-cdn.com/v4/letter/b/a9a28c/32.png) [@Blake](https://boards.straightdope.com/u/Blake)\ **Post date:** [June 3, 2009, 1:08am UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/11 "2009-06-03T01:08:12Z")
> [@ghardester](#): > > Really? Round Up is banned? All it does is shut down an enzyme in the plant that is needed for growth, it isn’t poison. All arsenic does is shut an enzyme in the plant that is needed for growth. Do you also consider arsenic not to be a poison? ---
**Author:** ![chacoguy](https://avatars.discourse-cdn.com/v4/letter/c/50afbb/32.png) [@chacoguy](https://boards.straightdope.com/u/chacoguy)\ **Post date:** [June 3, 2009, 1:57am UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/12 "2009-06-03T01:57:54Z")
Gasoline will kill pretty much anything. ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [June 3, 2009, 2:07am UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/13 "2009-06-03T02:07:37Z")
> [@Blake](#): > > Bugs are a specific type of sucking insect. To an entomologist, yes. But in “the common usage of the man in the street” (catchy phrase - glad you used it) the term refers to the panoply of insects, arachnids, and various other creepy crawlies. Surely you can see he wasn’t specifying the hemipteroids. ---
**Author:** ![Dallas\_Jones](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dallas_jones/32/3277_2.png) [@Dallas\_Jones](https://boards.straightdope.com/u/Dallas_Jones)\ **Post date:** [June 3, 2009, 2:09am UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/14 "2009-06-03T02:09:45Z")
> [@Chronos](#): > > So how would you describe shutting down an enzyme needed for growth, if _not_ poison? It is specific to plant growth. ---
**Author:** ![Blake](https://avatars.discourse-cdn.com/v4/letter/b/a9a28c/32.png) [@Blake](https://boards.straightdope.com/u/Blake)\ **Post date:** [June 3, 2009, 3:11am UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/15 "2009-06-03T03:11:42Z")
> [@Gary\_T](#): > > To an entomologist, yes. But in “the common usage of the man in the street” (catchy phrase - glad you used it) the term refers to the panoply of insects, arachnids, and various other creepy crawlies. Surely you can see he wasn’t specifying the hemipteroids. That’s the problem. He was correcting a correct common and technical usage of pesticide while simultaneously using the word bug in a very sloppy manner. It’s either one or t’other. Can’t be both. > [@ghardester](#): > > It is specific to plant growth. So? Rattlesnake venom is specific to animals. Does that mean it’s not a poison? A poison is something that kills by poisoning. No mention in any definition I’ve seen that suggests that a poison has to kill all lifeforms across all kingdoms. If your point is that it’s not poisonous to humans that’s fair enough (though debatable). But you can’t contend that it’s not a poison. ---
**Author:** ![Tom\_Tildrum](https://avatars.discourse-cdn.com/v4/letter/t/e95f7d/32.png) [@Tom\_Tildrum](https://boards.straightdope.com/u/Tom_Tildrum)\ **Post date:** [June 3, 2009, 3:36am UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/16 "2009-06-03T03:36:03Z")
The salient feature of RoundUp is not that it’s not a poison (it is) but that it reputedly decomposes quickly into naturally-occurring elements. That’s what supposedly makes it comparatively harmless. ---
**Author:** ![Blake](https://avatars.discourse-cdn.com/v4/letter/b/a9a28c/32.png) [@Blake](https://boards.straightdope.com/u/Blake)\ **Post date:** [June 3, 2009, 3:56am UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/17 "2009-06-03T03:56:19Z")
> [@Tom\_Tildrum](#): > > The salient feature of RoundUp is not that it’s not a poison (it is) but that it reputedly decomposes quickly into naturally-occurring elements. That’s what supposedly makes it comparatively harmless. Well, no. What makes Glyphosate comparatively harmless if the fact that, even in its pure form, it is for all practical purposes biologically inactive in mammals and is very rapidly excreted unchanged. It doesn’t need to decompose. You could drink a gallon of the pure liquid and get nothing worse than a bloated stomach. (caveat: there is some sketchy evidence of long term health effects, but best science says it’s harmless). Moreover Glyphosate doesn’t decompose especially fast. What it does do is rapidly bind to minerals in the soil, so it doesn’t travel and isn’t biologically available for uptake while it decomposes. ---
**Author:** ![Jackmannii](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jackmannii/32/311_2.png) [@Jackmannii](https://boards.straightdope.com/u/Jackmannii)\ **Post date:** [June 3, 2009, 4:02am UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/18 "2009-06-03T04:02:11Z")
I would second the idea of using a cheap propane torch to burn out weeds in walkways. Tough weeds, however, will survive surface singing and regrow. In any case, you should check with the Ontario Ministry of Fingers In Every Pie to make sure that propane torches are sufficiently earth friendly (since you _are_ motivated by selfish concerns about cosmetic appearance). I’m sure some bureaucrat will be delighted to help you. ---
**Author:** ![Savannah](https://avatars.discourse-cdn.com/v4/letter/s/b3f665/32.png) [@Savannah](https://boards.straightdope.com/u/Savannah)\ **Post date:** [June 3, 2009, 4:04am UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/19 "2009-06-03T04:04:09Z")
I use the boiling water method–at least, I have, and it worked. I need to do it again at the front of our place; I was just thinking that. No way in hell am I wasting my good gin on weeds! ---
**Author:** ![Tom\_Tildrum](https://avatars.discourse-cdn.com/v4/letter/t/e95f7d/32.png) [@Tom\_Tildrum](https://boards.straightdope.com/u/Tom_Tildrum)\ **Post date:** [June 3, 2009, 4:06am UTC](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517/20 "2009-06-03T04:06:23Z")
Ignorance fought! Thanks. [Next page](https://boards.straightdope.com/t/garden-work-weeds-in-walkway-cracks/498517.md?page=2)