Where do tree roots get all their strength from?

[clop]

In a pot in my garden I have planted an acorn. It's growing steadily but I know that unless I transfer it to a bigger pot in the future, it will always be confined to that pot. The roots aren't (and never will be) strong enough to break through the pot.

But when I ride my bike along the local cycle tracks in Adelaide I frequently encounter bumps where tree roots have pushed the tarmac up. I've seen the same thing happen where tree roots have grown under roads, and in many cases the roots have managed to push the road surface up and actually break it. The force required to do this must be very high - I certainly couldn't push a road surface up from underneath and break it.

Where is the root getting all the strength from? Surely the division of plant cells isn't strong enough to lift a 2 ton road? It's the same cell division as my acorn is performing in its plant pot?

clop

[Jens]

Where is the root getting all the strength from? Surely the division of plant cells isn't strong enough to lift a 2 ton road? It's the same cell division as my acorn is performing in its plant pot?

clop

I suspect the reason the acorn can't break the pot is because the holes in the pot are too small for the roots to infiltrate into and subsequently break. It may be the same reason that plant roots don't break into plastic bottles.

[Ronald Brak]

There was a science fiction story where a human sabotaged a Berzerker space ship with the mechanical power of a growing melon.

[Maksutov]

It's called hydraulics. In this case, biological hydraulics, and most specifically tree root hydraulics.

[Peter Wilson]

I believe it is osmotic pressure. When a cell divides, it loads up on ions; the salty inside of the cell draws in water, and resulting osmotic pressure is immense.

The reason sapling won't crack its pot is it has nothing to push against. The tree with its root under the tarmac has solid earth below, and tarmac above. Both are pretty rigid, but the less rigid of the two gives.

Plant your tree in the ground--pot and all. When the pot cracks (will take several years), you'll know that the tap root is now bigger than the hole in the bottom of the pot.

Trees cannot break steel, however. I have seen trees staked-up when they are young with metal wire loops, then forgotten about. When years pass and the trunk expands to the size of wire loop, it gets stuck, or "choked." I clip these when I find them...if I have wire-cutters handy.

Anyway, trees can break concrete, but not steel.

[BigDon]

Uh guys,

I was a greenhouseman for four years in a huge greenhouse complex and I've seen plenty of split pots both plastic and wooden.

Ron, I read that one too! (Though my favorite was the novel Blue Death)

[Maksutov]

Uh guys,

I was a greenhouseman for four years in a huge greenhouse complex and I've seen plenty of split pots both plastic and wooden....

Same here back in 1966 working a job to pay my way through college. The spring scramble when the usual Connecticut April or May "late" frost threatened was quite an experience.

I got fired because the Dutch owner thought my hair was too long and didn't like my boots. The boots were really useful when traipsing through the muck most plants really enjoy.

Tell me about the fractured pots. Ice and roots are incredibly strong.

Therefore, I think the intro should have been "Uh guy,".

[Dragon Star]

I've seen roots from tree's fracture and break huge, solid rocks as well.

[Peptron]

Anyway, trees can break concrete, but not steel.

Heck, the roots of a big tree in front of my friend's home pierced a sewer. The sewer then proceeded to empty itself in his basement...
Sad thing is that they saw that coming a few years before and warned the city about it, but they didn't take it seriously.