That’s a rather cleanly cut stump for 4500 years ago. I’m left wondering what the story there is.
Brings to mind an earlier event that exposed a woodhenge in Norfolk:
I was wondering the same thing.
Couple of possibilities:
- the inhabitants 4500-6000 years ago had the means to cut those trees like that – not inconceivable, as we moderns have a strong tendency to underestimate the knowledge and abilities of our forebears
- the wood was scavenged more recently; presumably any trees left standing would have stuck out high above the muck.
- seems more likely to me. Crosscut saws and bronze do not compute.
Wikipedia’s Saw entry:
In ancient Egypt, saws made of copper are documented as early as the Early Dynastic Period, circa 3,100–2,686 BC.[1][page needed] Examples of saws and models of saws have been found in many contexts throughout Egyptian history. Particularly useful are tomb wall illustrations of carpenters at work that show sizes and the use of different types. Egyptian saws were set with the teeth projecting only on one side, rather than in the modern fashion with the more advantageous alternating set. According to Chinese legend, the saw was invented by Lu Ban.[2] In Greek mythology, as recounted by Ovid,[3] Talos, the nephew of Daedalus, invented the saw. In archeological reality, saws date back to prehistory and most probably evolved from Neolithic stone or bone tools. "[T]he identities of the axe, adz, chisel, and saw were clearly established more than 4,000 years ago."[4]
Egypt and Greece are not Wales. Not by a long shot. Egyptian saws cut on the pull stroke, whereas I look at that stump as being crosscut (which is why i said crosscut saw).
Are you intending to state that it was an ancient welsh bronze or copper crosscut saw?
Seems fairly far fetched. Seems much more likely that this was scavenged at some point since then using more modern tools.
Especially considering the rest appear to be ^ topped, suggesting an axe or decomposition.
It is possible…
Most likely sawed off at a later date or scrubbed smooth by sand.
I tend to agree that later scavenging is more likely, even much more likely, but wouldn’t completely rule out the first possibility.
At some point after those trees were cut, this stand of trees was entirely forgotten. So one way or another, it happened a long time ago.
Presumably there are some clues elsewhere in the area. I’m thinking buildings, carvings, furniture etc. made with the scavenged wood, whether extant or buried/ruined. If they were cut less than, say, 500 years ago I’d expect it to be possible (which is not to say easy) to find some of the wood still in use somewhere.
If I lived around there in the last couple hundred years, I’d have cut off whatever stump kept poking the bottom of my boat.
Doesn’t have to be a cross-cut saw. There were also rope and chain (non-powered, natch) saws. Cannot give a provenance, and I note there is very little evidence of such tool usage, and the study of this new site is on-going.
Don’t you think these would have been cut at a time when the trees (or at least the cuts) were above the waterline?
Sawing through a stump underwater, even 200 years ago, actually sounds slightly less plausible to me than a forgotten Bronze-age technology for cleanly sawing through a large oak.
not at all. i assume the stump top was pointy like the rest and maybe slightly above the muck, and was exposed say circa 1940s, and someone with no sense of archaeology went out to deal with a navigation hazard.
it just does not look like something cut thousands of years back, nor with a rope saw.
I’m trying to formulate some joke about what Ken Ham could learn about trees being submerged underwater for over a year, but it just makes me sad. He’d find something to reaffirm his preferred narrative.
Visible for the first time in centuries… Unless you were watching TV back in 2005: https://www.youtube.com/watch?feature=player_detailpage&v=dz5Yr-BLQQM#t=405
OK, as @rupertj already pointed out we have a headline problem - “visible for the first time in centuries” is just not true. So, whether the reason was navigation or not I’m now pretty well convinced any such cuts are relatively recent.
Edit: at 9:44 of the video linked by rupertj, you’ll see a scientist’s saw half way through a trunk. I don’t think it’s the same trunk in the photo posted here, or even in the same stand of stumps, but it’s irrefutable proof of recent sawing. 
I have only skimmed this study from 1938, but it doesn’t seem to mention the cuts:
Also:
Why, these are the very trees that Noah felled to build the Ark! How darest thou imply otherwise!
4500 yrs – does that coincide with the Great Flood?
Somebody get Percival Dunwoody on the line, STAT!
Isn’t Portmeirion on Cardigan Bay? I’m thinking Rover.
