In some shots of the rioters on Wednesday, the ones climbing a wall, there is some kind of green growth hanging down from a parapet. I’ve seen vegetation growing from old buildings, and it was my understanding that it doesn’t do the building any good.
Some vegetation is worse than others. For example, some ivy is hard on masonry, but other varieties aren’t nearly as aggressive.
Aside from staining, can plants really harm such a building?
https://www.youtube.com/watch?v=k9FIg9SCOnQ .
– only semi-applicable, but it’s a good song. And plant roots can do astonishing things. They can indeed crack stone and concrete.
https://www.hascallandhall.com/blog/plant-growth-and-its-effects-on-masonry/ :
Another huge concern for a structure is plant growth (i.e. vines, bushes, trees) which might not seem concerning to the eye, but a closer look will show you how damaging this can be. Lots of plants can grow around and even up your structure which is inevitable, but what you need to be aware of is the root of it all. Plants have tiny root hairs that seek out opportunity wherever they can. Once an opening is found, woody plants can open joints and even dislodge stones. Once the root is into the joint, they then can crack that stone or brick as the root expands allowing water to get in, ultimately wearing the stone away and feeding more nutrients to the root. Once a root is into the structure and the cold New England winter comes, stone will crack when the root/water freezes.
How Do Plants Break Through Concrete? | CNY Sealing & Paving .
concrete contains microscopic cracks invisible to the naked eye. Plants have new cell growth at the tips of their roots. As the plant grows, so does the root system. The sensitive tips of the roots have the power to seek the path of least resistance for growth. Microscopic concrete cracks present this path for plants growing beneath your sidewalk.
Once a plant’s roots discover a microscopic crack in the concrete, they force their way into the slab. Even small weeds and seedlings have the power to displace concrete using potential energy from root growth. Over time, the plant’s continued growth can crack, break, or buckle the surrounding concrete – at which point you may see the plant break through the surface
Please forgive me, but as Og is my witness I thought you were going to say that some of those people seemed as smart as Brussel Sprouts.
My thoughts exactly! But…calling them Brussel sprouts is too much. I was leaning towards the pond scum category!
~VOW
Well, from this side of the ocean, these plants seems to be in pots included in the stairs. Roots can be a problem, but far less than savage growth. Do you have a precise picture in mind?
It’s Kudzu. Confederate Kudzu.