Years ago i was visiting a neighbor he had a tarp spread on the ground with hay spread out under it,,he was walking on top of the tarp and pressing his foot down everynow and then,,I said what ye'doin he said i'm puncturing spray cans under this tarp to keep the grass seeds from germinating when i put it on my garden,,I don't remember if he show me what it was or not,,But i can't find anyone thats ever heard of anything like that,,Has anyone here ever heard of it?If so what is it and where can i get it?

Makes no sense to me.

In fact, it sounds dangerous.

You can kill seeds with heat but it takes time and by the time you get the soil hot enough to kill seeds, you have killed all the soil microbes too. Unfortunely, the first microbe to grow back is always salmonella.

You would do better with Preen (the pre-emergent one in the yellow box).

Ditto Bill and Daisy. I can't figure out where the straw and spray cans come into it. What kind of spray cans?

Thats my question what is it? It keeps the seeds in the hay from germinating,,I don't know what would be dangerous about it,,its just like the cans of indoor foggers..

Could it possibly be that the aerosol in the spray can was supposed to prevent seed germination?

Yeah, it's the "puncturing spray cans" part that is confusing and sounds dodgy. Puncturing is not the same as spraying or fogging. Maybe just his wording. In any event, I've never heard of that method.

Puncturing is just the way of letting the chemical out of the cans,,then it does its job on the seeds,,The tarp is just to hold the cloud of spray in,,But the point is does anyone know what it is so i can get some,,No one seems to have ever heard of it,,And i know i didn't dream it,,I wish i had took more interest in at the time,,p.s. and it may not have been a spray,I assume it was,He said he had 4or5 can under there and was puncturing them with a nail on a board he made for each can,,

Sorry, I have no idea.

Forgive me please, but I have over 70 yrs of gardening experience under my belt. Not wishing to boast but, I have a doctrate in plant pathology and soil sciences. Never before have I heard of such a practice.

I agree that fire is usually accepted as being the final means of destruction. However, due to the grand method of creation. Many plants etc, actually require the fire treatment so as to begin their germination. So in some kind of conclusion. I have my doubts on this matter.

Use preen.

By your description, he probably meant the propellent in the can to suffocate the seeds. VERY dangerous (quite a few are flammable and puncturing cans isn't a safe way to let it out) and won't actually kill seeds. The heat from the tarp likely does more. (But as DaisyI pointed out, salmonella...) He is quite likely poisoning the ground under his tarp with the residuals. Don't do this.

And then there's all the stories about people blowing things (themselves, their houses) up by putting too many foggers in a closed space. I tried Googling different phrases to see if I could find something about killing seeds with punstured spray cans. I now know a lot about how to kill Puncture Weed seeds and a word of caution about foggers and houseplant health. The secret of how that might of worked may have died with the elderly gentleman.

Nice to see you Growmore.

Light Bulb Moment!! Years ago, the propellant in spray cans was different than it is now. So this question may be a moot point as you couldn't duplicate it again anyway. Like keeping a tree warm in winter with Christmas tree light strings. We used to do that!

DaisyI said: ... I now know a lot about how to kill Puncture Weed seeds...

😂😂😂