what plants tell about soil?

Hey growies. i got a whole bunch of kickxia elatine growing in beds and everywhere else. was wondering if anyone can tell me what this means as far as nutrients in soil and anything else about the soil profile. thanks!

This plant is a member of the Plantain family and so would most likely tell you the same things as any of the plantains.
If they're flourishing in your garden, that's a sign that you have low soil fertility.
Start incorporating more compost and manure into the soil in the area.
regular applications of Fish emulsion will help as well.

Ellie, your weeds will tell you just about anything you want to know. They are volunteers under the worst of circumstances, and tell you pH levels, water levels, mineral levels, clay or porous soils. Different areas of my clay hillside can be different degrees of porous, so it's surprising how some will do well in one area, and not another. If you can identify your main weeds and keep track, you'll be surprised what they are saying. Even something like poison oak needs a lot of water, and it might crop up someplace where you never imagined there could be extra water underground.

Some like acid soil, some like alkaline soil, some do well in dry soil. Some are okay in the wind, some like shade. I keep a pile of granite sand, and the thistles just love it, high in potassium. The thistles, when mowed and used as mulch with other weeds, will put that potassium back into the soil.

Some will have growth inhibitors in them, so you won't want a lot of those, but they still tell you what's going on. Anything related to a sunflower could have growth inhibitors. They have yellow flowers with multiple rather straight petals, sometimes scratchy leaves and stems.

What about Himalayan Blackberry? The vine will climb on everything in my woods. It weaves between the Alders and make the woods almost impassable. They have only come in in the last three years before then I didn't have any.

The Himalayan blackberry is actually a relative of the American blackberry and it thrives in the same soils, it will even take over and crowd out any plant species.
If you have this invader you have fertile soil, with adequate moisture. The best method for getting rid of it is to dig the root crowns repeatedly since the left over roots will sprout a new plant.
This is another plant that will take you a while to get rid of. It can thrive over a wide range of soil pH and compacted soil or loose soil.

Plants may tell something about the soil they grow in, but it seems to me that a lot of plant growth is plain old random chance, or is due to things other than soil, such as sunlight, water, or predators.

For example, I have an area in one of my fields where bindweed grows very well. What that says about the soil is that it is rocky, so my cultivation equipment can't get at the rhizomes as effectively.

One of my other fields grows a tremendous amount of very early spring ephemerals... That is because the field wasn't irrigated for 40 years and mowed a couple times during the summer, so the only things that could thrive there were plants that completed their life-cycles in early spring while there was still residual moisture in the soil, and before it was mowed. That says little about the soil. It says a lot about the rains.

My neighbors field grows a tremendous amount of curly dock. It has been a pasture as long as anyone can remember. The horses will not touch the stuff, so it reproduces unmolested. It doesn't grow in any of the nearby fields that have the same type of soil. So that says more about the predators than it says about the soil.

One of my fields has a hint of purslane in it. That is plain old random chance, because I loaned my tiller to someone, and it came back with weed seeds attached.

The north side of hills around here grow different species than the south sides. That is due more to differences in sunlight than to differences in soil.

Different plants grow in shaded areas than in sunny areas. That is due to differences in soil, sunlight, water, and perhaps wind patterns. How does one separate which influence is more important?

Using the old time methods to determine things about growing plants is multi faceted not singular in nature. I agree in part with you Joseph, but if you look at the whole picture, not just one part of it, you see the vision the artist intended.

I will use myself as the example here. I am a Scientist, I have a MS in chemistry, a MS in Biology and a BS in Horticulture. I have my own lab, so I can do most soil or plant testing in house.
I also do a lot of experiments to find best methodology for my soils and plants. I also pay attention to what nature tells me, in fact, I look to nature first and my science second.
This allows me to arrive at the point of being able to do the most good in the least amount of time with the least amount of money spent for the end result I want.

Bindweed usually grows where soil is compacted, loosening this soil is only one part of getting the stuff under control, you still have to physically remove the stuff by cutting it off or putting goats or pigs on the area to graze it down and so wear out the plants roots.
Sure, you could use poisons, but those also take more than one application, as well as polluting the soil, ground water, any thing else that grows in that soil. So this is not an acceptable (to me) solution. A commercial farmer will beg to differ with me, I guarantee it.

In truth, every plant that grows, anywhere on the planet, tells the story of the soil that it is growing in. It is our job to observe and understand what is being told/ shown to our eyes. We then have one part of the whole picture of that piece of soil. If we add the other parts, we can come to know the whole story.

All plants are opportunists to a a degree but everything does better where the condition favour them.

This site has been posted here before - I found it useful.
http://homestead.org/DianaBarker/LooktotheWeed/SoilIndicators.htm

When bindweed grows in my soil where I haven't amended it, I know from the other weeds that grow with it, what's in the soil. They all confirm each other. I don't think bindweed is fussy, so I don't rely on it to tell me much, other than I'd better get busy and stop it! Once I've amended the soil, it's up to me to remember what I put there, and in what state of decay I think it is.

Last summer I'd just about had it with the bindweed, and decided to smother it to death, not really hoping for much. But starting in late summer I put at least 10 inches of rotted straw and weeds over it, the densest stuff I could find, no or very little light getting through, and it worked. We had normal rainfall, and there was much less to contend with this year. So now I am maintaining thick mulch all year and mowing the paths it gets into. And whenever I mow bindweed, I take the basket of cuttings way far away. I don't put them back on the raised bed section.