Temperate tree seeds that produce mucilage?

I was thinking about replacements for plastic l, cardboard and other sheet mulches and landed on wood veneer...

Wood veneer cost too much and would be difficult to make at home.
Woodchips, sawdust, the shavings from a plane, autumn leaves, these are all low cost wood products we could put in a sheet mulch, but they are not in sheet form.

Industry uses glues and or high energy to turn similar materials into sheet goods.
These things cost too much, use a lot of energy  and introduce toxins.

Mucilage is a natural glue of sorts.
Sesame,okra,flax and chia are some of the seeds that mucilage can be sources from.
They are also food, and annual plants.
I've looked for trees with seeds that would produce mucilage, but only found quince.
Before I move on to other plant glues, like pectin, I thought I'd ask y'all if you have any ideas.

For what it's worth, Chinese Yam seems like a good perennial source of mucilage, one that could grow in a tree layer.

Slippery elm root and Marshmallow root (or the whole plant) might work.

Maybe some fungi? I have no particular suggestion.

I recall the Kentucky Coffeetree seeds being goopy, I wonder if there's enough mucilage in those to be useful to you.

Hmm, I have experience with the KY coffee tree seed and their stickiness.
It might be perfect, it seems to make tons of seeds and there doesn't seem to be a lot of things that eat it.

Not a tree, but... Plantain, Plantago major, has the most mucilaginous seeds I've ever seen. Made "porridge" from them once, and had to keep adding water over and over again, since it just kept on thickening. When gathering the seeds, your hands had better be completely dry, or the seeds will glue themselves to your skin. I suspect this is part of what makes plantain so good at spreading. Anything passing the plant in wet weather gets coated with seeds.

I love that plant, but I can't seem to get it to spread in my garden!
On a similar note, last night I was making waffle batter with oat flour and I had to keep adding milk so it could remain liquidy.

William Bronson wrote: I love that plant, but I can't seem to get it to spread in my garden!
On a similar note, last night I was making waffle batter with oat flour and I had to keep adding milk so it could remain liquidy.

Do you have a part of the garden where the soil is a bit compacted? The edge of a path or driveway, maybe? That would be a good place to scatter plantain seeds and see what happens, unlike most plants they seem to really enjoy it...

That's a good point, I'm usually planting them in nice soft garden beds, or weeding away competition.
Maybe they do better with a challenge.

Sassafras leaves and twigs are mucilaginous. So are Japanese knotweed shoots, but they are highly invasive. You could forage for them, but I wouldn't plant them. I don't know if they will work for your purpose, but it might be worth looking into.

I love the smell of sassafras and I've recently listen to a podcast that makes me think they have been demonized as an edible.

Cacao husks are a mallow and contain a lot of mucilage. However they encourage large growth of fast growing mould (not mushrooms) which might not be desirable. Sawdust is the best weed suppressing mulch I’ve found—part of the reason being because they bind up nitrogen. Sawdust locks together in a solid sheet after a good rain and it also adds carbon and stop evaporation like nothing else—except unlike cardboard it allows water in as well as keeping it in.

Would a mix of the two perhaps be more effective than either in isolation?

Here in Utah, common mallow is one of the most abundant "weeds", and the whole plant is full of mucilage, so you don't have to pick off the seeds.