Strange black roots in raised bed

We just finished our first growing season in our new house. We moved in just over a year ago and the house came with a couple of raised bed gardens that the previous owners had put in. Last spring, when preparing the beds for planting (we added a fair bit of garden soil mixed with manure compost), I noticed that there were roots in the soil (no plants) but I didn't think much of it and figured they were just leftovers and would die off.

Well, they didn't die off in fact these roots started taking over. By mid to late summer, I was pulling potatoes out of the garden that were wrapped in these strange roots. That being said, nothing in the garden seemed to suffer (tomatoes, green bean, potatoes, onion and garlic all grew extremely well).

Last weekend, I decided to turn up all the soil in the garden to see if I could get rid of the roots. The bed is about 16' x 6' x 16" and the roots were present throughout and at all depths (not surface). The previous owner had put landscape cloth down at the bottom of the bed and the roots had grown into it as well. I couldn't find any apparent source, it was more just continuous growth. There has never been anything visible on the surface of the soil to suggest a source and I didn't have a weed problem through the growing season/

The roots have dark, almost black outer coat that peels off and they are very kinky and elastic (they 'snap' when you pull them). They actually look man-made but they grow so I know they aren't. The thickest bits I found were only a couple millimeters in diameter and the majority were thin and wiry. I pulled out enough of this stuff to fill a grocery bag.

There is only one tree in the vicinity of this bed, it's a magnolia (I'm pretty sure) and about 10 feet away. As I said, there is nothing growing in the garden that could produce this however, it does appear that the previous owner used the bed as a bit of a dumping ground as I saw evidence of potting soil in there. I'm dumbfounded as to what could be causing this but I'd like to get rid of it if I can. It's honestly a bit creepy.

Thanks

Hi Madison, So sorry that you have had problems with your unidentifiable roots within your soil.

Is there any chance that you could dig some up and send in a picture for others to see, this might give you a better chance of PROPER ID and quicker too.

There are several plants that set down roots that are black and tangled etc, so it is important to give you correct answers,

I have clumps of black roots through a bed / border I have just emptied too BUT these roots are left over from some Ferns that had began to grow there as the bed became shaded from over head trees so there are several answers BUT you need the correct one.
Hope you can get a picture sent in as it will help better than written description.

Kindest regards.
WeeNel.

Thanks WeeNel. Here are a few photos including a photo of the bed. As I mentioned, there is nothing I have seen growing above ground in the bed that could have produced this. The bed was empty of all plant material when we moved in last year but the roots were in the soil already.

I should mention too that they seemed to grow extensively over the summer.

madison I believe these are roots from one of the nearby trees. Tree roots grow looking for dinner and a drink, and can go long distances, much further than the "drip line" of the tree. You have conifers nearby as well as the magnolia (I can see the trunks in your photos), and the roots could be from either one. The probably loved being fed and watered over the summer, and grew up into the raised bed.

Grown up through the landscape fabric?
I have had roots attach from topside down into but not grow up through unless through a seam or breach

Absolutely. I agree that these are likely tree roots, from one of the surrounding trees. Our composters (which are open to the ground) become colonized in the lower levels by tree roots from surrounding birches and other trees.
While they may make it difficult to turn over the soil in the garden area, at least to a deep level, I assume, it's very good to hear that they are not causing suckering, nor causing particularly noticeable problems with growing your garden. Unless you feel it necessary to actually get rid of the trees (which would seem to be a shame), it sounds like it's good to know the cause, though it's not really causing a significant problem?

Thanks everyone for your thoughts and ideas. Now that I put everything together, I think it is quite likely that they are tree roots that have come up through cracks & seams in the landscape cloth. I just never thought the roots would travel that far. They don't seem to cause any harm (other than wrapping themselves around some of my potatoes) so I will continue to yank out as much as I can each season and just garden around them.

One of the best parts about my neighbourhood is the fact that we essentially live in the middle of a forest and are surrounded by big, beautiful trees. I guess this is a small price to pay for that :-)

It looks absolutely lovely there. I think if you yank out what roots have grown up into the raised bed soil each fall or spring when you prepare for the next year, you can continue to grow good crops (at least until the trees get so big they shade out your sun-loving crops). I suppose you could try to replace the landscape cloth with a new layer, without any defects. I have never tried that so I can't speak from experience.
I would like to invite you to contribute to the PNW forum, I am hoping to resurrect it from a quiescent state! You are just a few miles up the road from me. We have a climate unlike any other, and it is really nice to "talk" with other gardeners from around here.

Ten feet is not far at all!
Glad that it sounds like you can live with it. :-)

Sorry Madison, I've been away a few days and just doing catch up.
Looks like all the others have helped you out as happens here on Dave's, the root mass I had came from digging out ferns (these grow like mad and multiply here in my shaded wood edges, the roots look like that wire wool you buy for polishing metal etc. all entwined.
I agree that some tree roots will grow like a wire mesh just under the soil as these fine roots are the ones that go searching out for water where as, the thicker roots that spread outwards and down while spreading, these thicker roots are the ones that give the stability to the tree to prevent it from blowing over.
Try find the names of the trees closest to your yard then scrape some soil away close to the tree, you will then know IF that tree is the one that is sending out these scrambled up roots.

You dont have to go out and do all the searchings I suggest Madison but IF, like me your trying to establish a garden beside woodlands, it helps to know what your main enemy is regarding steeling moisture from the soil and eventually giving you a headache by shading the plot.
I'm sure all the help from myself and all the others will go a long way to helping you out.
Enjoy your new gardening hobby and make sure you have fun along the way too.
Kindest Regards.
WeeNel.

Sorry Madison, I've been away a few days and just doing catch up.
Looks like all the others have helped you out as happens here on Dave's, the root mass I had came from digging out ferns (these grow like mad and multiply here in my shaded wood edges, the roots look like that wire wool you buy for polishing metal etc. all entwined.
I agree that some tree roots will grow like a wire mesh just under the soil as these fine roots are the ones that go searching out for water where as, the thicker roots that spread outwards and down while spreading, these thicker roots are the ones that give the stability to the tree to prevent it from blowing over.
Try find the names of the trees closest to your yard then scrape some soil away close to the tree, you will then know IF that tree is the one that is sending out these scrambled up roots.

You dont have to go out and do all the searchings I suggest Madison but IF, like me your trying to establish a garden beside woodlands, it helps to know what your main enemy is regarding steeling moisture from the soil and eventually giving you a headache by shading the plot.
I'm sure all the help from myself and all the others will go a long way to helping you out.
Enjoy your new gardening hobby and make sure you have fun along the way too.
Kindest Regards.
WeeNel.