An array of nozzles, from which jet high-pressure jets of liquid nitrogen, aimed so that with one discharge your garden grass, bowling green or sports field surface is frozen and, by force of the jets alone (possibly), harmlessly snapped at your preferred lawn length.
-- calum, Feb 08 2012

Laser Lawnmower Laser Lawnmower
[zen_tom, Feb 08 2012]

If you can do it with hair, then why not grass? freeze_2fbreak_20hair
[ldischler, Feb 09 2012]

Excellent! [+] What could possibly go wrong?

(...here, kitty, kitty, kitty...")
-- Grogster, Feb 08 2012


I like the idea of a completely silent lawnmower
-- hippo, Feb 08 2012


Me too - and liquid nitrogen would supply a suitably misty atmosphere for the laser-based lawn-invigilation system.
-- zen_tom, Feb 08 2012


A lawnmower which made ice-cream would be welcome too - for those hot summer days.
-- hippo, Feb 08 2012


I could be wrong but I don't think that the grass will be a ble to fix the nitrogen if its all liquid like that...
-- 2 fries shy of a happy meal, Feb 08 2012


Would the grass recover from being frozen? Given its high surface area/volume ratio, I would think it would be frozen quite quickly (which would be conducive to survival), but I don't know if it would survive the process.

Your lawn would also have to be well-drained, so as to allow the heavy nitrogen gas to run off and not suffocate your plants.
-- Hive_Mind, Feb 08 2012


//Wound the grass recover from being frozen?//

That's the whole point, we want to kill it off! Less grass, less &#%@* mowing. And it might be cheaper than keeping the whole yard paved over.
-- Psalm_97, Feb 08 2012


Your device could cut the sod into a strip, pick up the strip and roll it over, and dip the inverted portion into a tray of LN2 to the desired depth. As the sod passes the next set of rollers, the frozen tips would get broken off. Flip it over the rest of the way, and put it back down.
-- lurch, Feb 08 2012


I have wondered what would happen if you dropped a big tank of liquid nitrogen on a wild fire. Would the sudden drop in temperature and massive blanket of nitrogen gas have a quelling effect?
-- not_only_but_also, Feb 09 2012


Baked already by Joni Mitchell (The Hissing of Summer Lawns)
-- xenzag, Feb 09 2012


Oh, [xenzag], now you've done it. I fought the lawn, and the lawn won.
-- normzone, Feb 09 2012


Tenpole Tudor - "Swards of a thousand men"
-- hippo, Feb 09 2012


//I fought the lawn, and the lawn won.//

Happens every summer here. Some days are just too, too hot. :-/
-- Psalm_97, Feb 09 2012


Aqualawn my friend,
don't you verge away unfreezy.
You poor old sod, you see it's only me...

//You're not wrong but you've entirely missed the point.//

tss.
If you miss the point, none of the grass gets cut at all.
-- 2 fries shy of a happy meal, Feb 09 2012


This liquid nitrogen's going to be describing a parabola. If you squirt it hard enough to make that parabola virtually flat over your lawn, then there's going to be quite a lot of overshoot, isn't there?
-- pertinax, Feb 09 2012


You calibrate volume so it vaporizes in the heat of the day before it gets much past your yard. As an added bonus, it gives the neighbors incentive to train their dog to stay well away from your yard, which reduces the number of piles you have to be careful not to step in.
-- Psalm_97, Feb 09 2012


//This liquid nitrogen's going to be describing a parabola.// Actually, it's [pertinax] that's describing a parabola. The solution is precision grading so the grass grows on a perfectly parabolic hill.
-- mouseposture, Feb 10 2012


Picture windows, beware.
-- RayfordSteele, Feb 10 2012



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