When trees fall

Sean Freeman

This is a series of pics and video from a UK community college (Gr 11-13 for Qlds!)
I post it because of the unusual nature of actual video of failures, NOT because I think such failures are common or that the consequences of such failures are often serious...neither is the case....I post it because of the voyeristic interest it generates!

Principal averts disaster | Uckfield Community Technology College

For those amongst you who like post mortum dissections, check out the unnatural root plate in the pics...geee I wonder why it fell??

bigshea13

looks like he might have gotten a good whipping if he was a little slower.

Sean Freeman

Yes no question he put himself on the line there to try to make sure noone got hurt, reflects very positively on his character as the principal

Here's another root plate soil failure under powerful wind loading

I've got a couple more interesting ones but having trouble tracking them down.

playfordtree

Wow, two very close calls there Sean.
I like the way the bloke in the car gets out and shakes his hand.
"thanks mate, you could have just saved my life there"

Sean i don't realy know the difference between a natural root plate and an unnatural plate.
I could see why the second tree would fail, given it was so close to the road.
What about the first one though?
Can you explain how it was unnatural?

Cheers mate

__________________
Euthanizing South Australian Trees
since 2007

Sean Freeman

I'll certainly have a go, though I should be a bit clearer about just what I mean.

We accept that roots grow anywhere they can find conditions that are favourable to their growth, and will decline and die back where conditions become unfavourable.

Even in non-human affected environments...wilderness in other words...soil conditions can be very variable in a small area, leading to greater volumes of roots in parts of the root plate in comparison to others......so.......I'm not suggesting that trees always have neat symmetrical root structures they don't, but the lack of symmetry is not uniform or in neat patterns when we see that we can be pretty safe in saying human factors are at play.

There is little difference inthe two examples I posted, only one os more obvious than the other....and yes there are other important factors at play, especially the cohesion in the soil structure itself, affecting the resistance to wind loading in the canopy.

In the case of the school tree we can see in one pic the area we would expect to see roots growing from the stem into the surrounding soil profile.....yellow area


I would have expected to see much more damage to the path surface as roots were pulled up out of the ground, even if they were to break healthy roots will lift the soil surface first and there should be evidence of that there is very very little disturbance...therefore very very few roots growing into the area of the path.


Perhaps the path was cut down and the surface roots removed during that process or the path was only lightly scraped and years of compaction and resurfacing have created a most inhospitable environment for root growth....whatever the case the straight edge of missing roots matches the edge of the path too perfectly this is not natural, this is a major loss of structural stability in the precise part of the root plate that was critical to holding up the tree under this particular wind event.

BTW the trees can also be seen to have been trashed through years of stupid lopping, adding to their woes creating major strain to the tree system, weakening defences and commiting massive amounts of stored carbohydrates to regrowing removed portions (big portions) of live canopy.

Remember all trees will fail under the right (or wrong!) conditions, what we can say is that inadvertent illconcieved and ill informed human actions have led to this event, not just the soil and root damage but it is in my opinion in this case the major factor.

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Treelore

As god is my witness I swear that second shot is a Silver Maple a client asked me to remove and couldn't afford either pruning or removal. Either that or identically similar situation any way of finding out adress???

Sean Freeman

I guess you could try to contact the original poster of the vid through youtube?

playfordtree

Thanks Sean,
perfect explanation.


Just out of interest, if someone had been using a heavy duty poison to control weed growth on the path, could that affect root growth as well?

__________________
Euthanizing South Australian Trees
since 2007

Sean Freeman

Yes you're right Playford, use of broadleaf herbicides means slow death to trees, so it certainly would be a factor....the weed and feed type used on many lawns here and elsewhere are a real problem for trees growing in turf areas.

playfordtree

Is there a broadleaf poison you can use that doesn't cause problems to the neighbouring trees?

__________________
Euthanizing South Australian Trees
since 2007

Sean Freeman

Not that I'm aware of.