The extraordinary physics of dried pine needles

This is as mundane and pointless as it gets. A single response would be one more than I expect or deserve. But I have to ask…

A couple of months ago, when we finally took down our Christmas tree, we were left with a giant pile of dried-up pine needles. Each needle was about a centimeter long and 1-2 millimeters wide. Pretty standard for needles, I’d say.

Before vacuuming I scooped up some of them into a dust-pan, and was startled to notice that a few of the needles seemed to be popping up into the air on their own. They were like Mexican jumping-needles, launching themselves forcefully out of the dustpan and into the air!

Curious, I did an experiment. I held the dustpan (full of needles) at a 30 degree upward tilt, so that none of the needles would slide out. Then I jiggled the dustpan ever so slightly, using as little force as I could manage. With each jiggle three or four needles went flying away, up and out of the dustpan, using the slope like a launching pad. It was as if I had flicked them hard with my finger; they flew about three or four feet away.

My questions are:

Has anyone else ever noticed this puzzling phenomenon?
Can anyone explain what’s going on here?

Gratefully,
-P

Two responses come to mind.

  1. Wait- you’re supposed to take down old Christmas trees? I thought the old ones were supposed to fall over and decompose, thus recreating the natural forest floor in a wonderful example of the circle of life in the privacy of your own home.

or

  1. Check with family members. Someone may have spiked the eggnog.

Wow! you took your tree down already? :slight_smile:

I have nothing else to add

Static electricity. The pine needles and the dustpan had the same electic charge, because the needles are somewhat conductive. When you jiggled the pan, it broke loose the weak molecular adhesion force holding them down and allowed the like charges to repel each other, propelling the needles outward.

Many parts of the flying needle are credible.
Ewell

Was the dust pan plastic? My best guess would be that it has something to do with a static charge built up when you swept them off the carpet, aided by the typical low winter humidity.

The last time I had a real Christmas tree, it wasn’t just pine needles that needed to be swept up. It appeared as if there was a multitude of little specks of dirt, or something. They turned out to be thousands of spider hatchlings. At least there was no mystery why they were moving.

A little tip: If you ever encounter such a hatching, just use a vacuum hose. I found out that sweeping results in a whole bunch of tiny squashed spider stains on your carpet.

Was there a little mouse in a blue robe with white stars on it, running around waving a little wand?

lieu eats pine cones.

That isn’t the scary part… it is the story of what happens to lieu a few hours later as the pine cone migrates… south…

Okay CuriousCanuck, I googled on “pine needles and wind” and per your comment substituted the aforementioned rectal outburst for “storm”. Here’s what we’re left with…

El nino, my ass.

I’m glad I received some interesting static-electricity-related answers before my thread was hijacked by strange pine-cone-eating flatulence-Googlers!

-P

Heh, meant to apologize for that. Actually I did a fair amount of Googling and couldn’t find anything more informative than what Q.E.D. and Skelji proposed. Their answer very well might be the most plausable.

Be careful. I understand that dried pine needles are very flammable, due to the oil in the needles.

Omg so funny. I happen to stumble on the Curiosity of the static we received from pine needles. Me and my nephew were cleaning off the patio chairs and realized that the pine needles were standing up toward our finger when we held it right above the pine needles. So we decided to google it and came across your pointless article but it really helped answer our question. That there is some sort of electro charge within a dried pine needle. Fun to experiment this with my 7 year old nephew.

Wow, you put up a Christmas tree?