Fascine Mattresses: Basketry Gone Wild | Hacker News Reader

Fascine Mattresses: Basketry Gone Wild

solar.lowtechmagazine.com

151 pointsggoo39 comments

> Willow wood becomes rock-hard underwater and almost doesn’t deteriorate. Research in the late 1960s showed that most fascine mattresses submerged for more than 100 years — some dating from the early 1820s — remained intact.

> Unlike most other tree species, willow tolerates saltwater and (temporarily) wet feet. As such, the coppice plantations could use land that was not suitable for agriculture.

> On impoverished soils, the Dutch planted alder trees between the willow trees. The falling leaves of the alder fertilised the soils and increased the lifespan and production of the willow trees.

Building long-lasting critical infrastructure using locally-sourced, carbon-negative resources! I have no idea about dykes specifically but I suspect today someone pitching a public works project based on woven willow would be laughed at -- and instead we would insist on pouring some reinforced concrete, using carbon-intensive cement, and it would begin falling apart from rusted rebar in 15 years.

What if we build it out of graphene instead?

There is an awful lot of knowledge that's been mostly discarded because it doesn't fit the "modern, industrial, profit-driven ways of thinking." Some of it is wrong, but an awful lot of it is simply "not easily to scale with machinery to maximum profits." Or, in some cases, just no longer considered stylish (stainless steel vs brass in hospitals being a case of "the new is literally worse than the old in every way that matters, while looking new" - the copper in brass is a biocide).

It's probably worth picking up a printed copy or two of LTM... modern society is running out of runway awfully fast.

> What if we build it out of graphene instead?

I think the implication (that carbon negative local materials are unscalable) is unfair. We haven't built anything huge with graphene yet and the per-gram costs are still crazy (e.g. on the order of $100/g). By comparison, this article is about relatively large-scale projects that we actually did, decades ago.

> Between 1954 and 1967, during works on the rivers throughout the country, they sank 1,200,000 km2 fascine mattresses to the bottom.

We're in a context where we simultaneously want to:

- build and replace infrastructure

- decrease our carbon footprint and go negative where possible

- protect large coastal areas from storm impacts

- prevent further habitat loss and loss of ecological diversity

And more recently we have become aware that sprawling international supply chains are a liability.

I think more than just concerns over whether something scales at maximum profit, we also have too much institutional inertia. "If we pick different materials, will permitting and oversight bodies be convinced about safety and longevity claims? Will workers need to be retrained? Will the planning process need to change? Better to just do what we've always done; it's easier."

To be fair, I suppose I _have_ heard people talk about carbon sequestration in cross-laminated timber for large buildings. I have not heard people talk about being able to source that timber locally, or in a way which is especially beneficial to the land.

https://investingnews.com/daily/tech-investing/nanoscience-i...

What's LTM?

Website where article is posted

> I suspect today someone pitching a public works project based on woven willow would be laughed at

Live fascine bundles and live stakes from willow are commonly used riparian restoration techniques.

Less elaborate and smaller, but the technique is still very much appreciated.

https://www.nrcs.usda.gov/Internet/FSE_PLANTMATERIALS/public...

The empress tree showed up on HN a little while back, specifically for its incredible ability to capture carbon. I wonder how well it would fare under water

https://www.bloomberg.com/news/features/2019-08-02/we-alread...

Willow tree branches are still used ins some modern hydrailic infrastructure construction today. And nor for historical reasons, it is still practical and cost effective. In the past the branches had two functions: as a rigid frame and as a filter layer (to prevent soil from being washed away from under the erosion protection). The frame functions to make the filter a rigid structure that one can sink to the bottom in a controlled manner by dumbing rocks on it. In modern construction geotextiles are used as filters, but these are sometimes made rigid with bundles of willow tree branches.

> Between 1954 and 1967, during works on the rivers throughout the country, they sank 1,200,000 km2 fascine mattresses to the bottom.

I have trouble squaring that with all of the Netherlands measuring only 41,543 km2, with rivers making up only a tiny fraction of that.

Perhaps conversion from 1,200,000,000 m2 was off by a factor of 1000, and they mean 1,200 km2 ?

Thanks for spotting the mistake. km2 should be m2.

Source: https://repository.tudelft.nl/islandora/object/uuid:1ed44c19... page 17

So that underwater basket weaving course was not a fluff course after all?

Of course it was! This is onshore basket weaving that's then floated into position and sunk. Different department.

But I mean, they could partially bypass the carbon cost associated with transport and installation if it was woven in place. Even more so if they could weave without costly respiratory equipment etc.

I remember that the top person in the math department in college had transferred from dance because it was too difficult.

They always present underwater basket weaving as being easy but I imagine it’d be quite challenging.

The idea is that underwater basket weaving has no utility in the real world, not that it is easy.

I had to drop the class because I couldn't hold my breath long enough to do much weaving.

For those who, like me, didn't get the joke: https://en.m.wikipedia.org/wiki/Underwater_basket_weaving

Was wondering what was up with the battery icon and the reddish warm overlay but I continued reading. At some point it started burning through my eyes and tapped the battery:

“This website runs on a solar powered server located in Barcelona, and will go off-line during longer periods of bad weather. This page shows live data relating to power supply, power demand, and energy storage. ”

A bit ironic that the site doesn't work properly in dark mode (which would use marginally less power on some devices)

Ah, I wondered what that was for! Now that I checked again, it's a couple of percent higher than when I read originally, because it's morning now in Europe.

This is fascinating. Worth noting that there appear to be still companies doing this today: https://www.vanaalsburgbv.nl/en/zinkstuk/

Enjoyable read overall. Always fascinating to see the human ingenuity involved in problem solving. I might have missed it in the article, but how do the fascine mattresses do the work of helping keep back the sea? By breaking up waves before they reach the shore?

The article is light on the actual function of the mattresses, but my reading is that they served to prevent erosion, and would prevent dykes and other structures from being undercut

They keep the soil of the dike in place, which would erode away without the "mattress".

The battery indicator is neat, but it's distracting when it's covering the whole page. Maybe couple ch of width in a sidebar would be easier.

Thanks, I had wondered what the two-tone background was for and didn't notice the battery indicator off to the side.

I wonder if this is the reason the Dutch (still) like to cut the tops off of willow trees every year or few. Just as the trees are starting to look great, a crew will show up and cut off all the branches, leaving a big fat nub on top of the trunk. And next year, it's grown back.

I do understand that with some of these trees, they can grow so big and so wide that the tree will split and possibly die (although there are some enormous trees still living with just partial shells of a trunk and no core).

The old-fashioned word for these willow twigs in English is "withies" (cf. Tolkien's "Withywindle" river in LOTR).

Coppicing has a long history in Europe (and some other parts of the world). Many other species are used for this, not just willows.

https://en.wikipedia.org/wiki/Coppicing

"Fascine" comes from the same Latin root as "fascism". The fasces was a bundle of sticks (sometimes with an ax embedded in it) that was used by the Romans as a badge of office. Mussolini's Fascist party appropriated the symbol. It's seen in many other places, though, including in the ceremonial mace of the U.S. House of Representatives and the seal of the U.S. Senate.

That's the "pollarding" referred to in the article. It is something that varies in popularity by region:

https://en.m.wikipedia.org/wiki/Pollarding

Meta: Interesting that a site called "low tech magazine" also appears to use "low tech" black/white dithered images... But I imagine it's a style choice.

I think they do it to reduce image size and therefore power consumption. Their server is solar powered.

Indeed: https://news.ycombinator.com/item?id=29067118

You can fit much more detail into the same file size with just a grayscale JPEG at quality 50. Then you lose the dithering style and transparency, though.

Reminds me of the Roman cement that lasts for centuries as well. The Dutch are interesting as they also have a strong agricultural bent.

I was just talking about that with someone. What makes it hold up? And are we talking about the material used to construct ancient structures like the Colosseum and aqueducts?

Something about crystal formation in the volcanic ash that the cement is made from, reacting with the volcanic rock the aggregate is made from. I'm not going to do it justice by getting any more specific, so here's an article for layfolk, and the associated journal article.

https://www.sciencealert.com/why-2-000-year-old-roman-concre...

https://pubs.geoscienceworld.org/msa/ammin/article/102/7/143...

Seems to me at first glance that this could make for a great carbon offsetting scheme

Dutch Genius at work.

This technique could be a great basis to build an artificial island. I'm waiting for some hard-core libertarian to show up and do that.

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