Spontaneous combustion?

[criddle]

What would cause a fire to start with no obvious sign of ignition?
Had a small grass fire that started Saturday, but there is no electrical, no motors or engines, no glass bottles, just grass and dirt. Closed place, shouldn't be anybody in there unless they were trespassing.

[jdavidson]

Trump’s fault

[Killer]

Broken glass. Lighting strike
Are there overhead power lines close by?

[flywise]

Could be a clump of old grass that got just the right amount of oxidation going on. Like a bale of hay.
mulch does that and cant tell you how many times i have gone on a mulch fire in a flower bed

[justletmein]

Oprah knows...

Aside from that, rotting vegetation can heat up a little right?

[Redfeathers]

Overhead electrical wires in the area, transformer etc. There is a site that shows lightning strikes when the info/area is keyed in, not sure if you had any lightning lately. Then as flywise stated, the right amount of oxidation in a clump of weeds/hay bale. Been called out for hay bales couple of times due to oxidation.

[gumbl3]

Other fires nearby? could be a spot, conditions are prime and those embers can carry a long way

[criddle]

No overhead wires within at least 1/4 mile of where it started.

No fires anywhere nearby, VFD even commented how this was the only one they had run on.

The oxidation/rotting grass- I can understand the mulch and hay fires due to their moisture content and how it relates to the bacteria that are working in that environment. But this is dry, dry grass. Not to say it's impossible, but I am not convinced on this.

Lightning is possible. I would have to see if I could track down if there was any on Saturday but here it was a clear (dusty) and windy day.

[camoclad]

Really dry, wind, dust, static?

[Sasqy]

Aliens playing with magnifying glasses !

[Killer]

That is weird

[Playa]

Really dry, wind, dust, static?

That’s possible.

in cotton bale fires a rock or piece of metal is heated from the friction of running through the stripper and can sit and smolder within the bale for weeks, and then the bale gets disturbed by being moved or even a high wind and it will suddenly combust.

I suppose something similar could occur if it were a pile of grass and had hit object inside the pile and wind blew the pile increasing the oxygenation

[canny]

Dang fireflys out there committing arson!

[Redfeathers]

criddle, we did not have any lightning on Saturday, so with everything you have stated, that is strange.

[Aggiebow88]

trespassing kids smoking a joint?