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How do plants extract nutrients from the ground?

permaculture.co.uk

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Re: How do plants extract nutrients from the ground?

#41

Post by philipkglass »

OrbitRock wrote: post #40
littlestymaar wrote: post #38

Earlier quoted context omitted.

Edit: this is wrong, see comments below. The correct answer is water though, not air. Air only accounts for the Carbon content of the tree, which is a big part, but still a minority. First, a live tree contains a lot of water (30-50%), that's why you need to let wood dry a lot before burning it. And there's something else: > Next we might look at water, but water is only made of hydrogen and oxygen, and the oxygen is…

I’m pretty sure the oxygen comes from CO2. Plant carbohydrates are made directly from CO2 in the Calvin Cycle. The Calvin Cycle is the source of all of the carbohydrate building blocks in the plant, and I’m pretty sure that oxygen from H2O does not enter the equation, just CO2 and some enzymes and cofactors. If so, the vast majority of the mass is from the air. (H might originate from water but its mass is pretty tri…

That's correct.

"Water Is the Source of the Oxygen Produced by Photosynthesis" (and CO2 is the source of the oxygen in carbohydrates)

http://www-plb.ucdavis.edu/courses/bis/2A/bis2A-F11/Photosyn...

Re: How do plants extract nutrients from the ground?

#42

Post by hinkley »

thomasfromcdnjs wrote: post #7
thatcat wrote: post #5

Earlier quoted context omitted.

Yea, you're welcome. I'm watching it rn, he def knows what he's talking about. I just disagree about the deep organic matter being beneficial, obviously don't use rotting compost as your source in a non porous soil though. I started a company that fractures soil and injects organic matter deep, filling fractures to create drainage and sequester carbon, we use biochar - it has a sandy texture and doesn't break down ve…

Oh that's such a cool company. I only recently got put onto Terra preta through my personal favorite gardener -> https://www.youtube.com/watch?v=DnTaWiO5Eso (he's funny lol) I'm going to try make my own ad hoc terra preta plots for fun too. Are you able to share any more information on your company? Who is actually buying this service? I feel like biochar is going to hit the main stream this year or next. Going to ma…

David has a guest video by a lady working above hardpan clay:

https://www.youtube.com/watch?v=goUfl4x8URc

Essentially all of the permaculture advice for breaking up clay appears to be failing on her hardpan, so she's started using broadforking, which is a sort of compromise between tilling and building soil from the top down. The speaker in this video is being a little more aggressive with the broadfork than most people suggest. The idea is to open the subsoil without blending the upper layers together, resulting in the organic matter-consuming bacterial bloom you get with tilling.

One variant of keylining accomplishes a similar trick on an even smaller scale: you put one long slice into the ground. Water and organic matter seep into that cut and fan out from there.

Re: How do plants extract nutrients from the ground?

#43

Post by ghshephard »

I love how it starts with: Over the past few years it has become clear that plants are able to extract nutrients directly from soil microorganisms in their roots. - something that was like a baseline of plant biology when I took it in high school 40 years ago, and, according to wikipedia, we've know for over 120 years.

Re: How do plants extract nutrients from the ground?

#44

Post by tastyfreeze »

I am so happy to see this on HN. A couple years ago I started learning about rhizosphere environment. It has changed how I look at my gardening. I now see healthy plants as a biproduct of feeding and caring for the soil. I imagine the soil as the external stomach of plants. When the soil is healthy plants thrive. I get excited when I start seeing larger arthropods in a new bed. It is an indication that the soil ecosystem is very healthy.

To head down the rabbit hole of soil health even further, learning about increasing the cation exchange capacity(CEC) affect on plant health has been fascinating.

Re: How do plants extract nutrients from the ground?

#45

Post by virtuscience »

thomasfromcdnjs wrote: post #17
markdown wrote: post #16

Earlier quoted context omitted.

> In short, plant roots actually love sand, silt and clay, and actually don't like organic matter around their roots as it causes rot. IMO it really depends on what you're trying to grow. I live in the tropics and there are a lot of tropical plants that do indeed thrive when the soil is heavy on the organic matter. I suspect it depends on how far/long these tropical plants have been bred away from their rainforest or…

Yeah, I think your absolutely correct. Gardening is actually quite hard in this regard. Everyone is always sharing tips and tricks, for different crops, different species of said crops, different climates, different soils, different hemispheres, different sides of a mountain etc I think there will be a cool database where you can filter by those factors one day but not sure we are quite there just yet.

"a cool database where you can filter by those factors" => this is one of the inspirations for Greg, the plant care community I've been helping to build after leaving Tinder.

Think Waze, for plants. We're about to launch on ProductHunt and HN, if you're interested you can check us out at https://greg.help.

Re: How do plants extract nutrients from the ground?

#46

Post by tastyfreeze »

thomasfromcdnjs wrote: post #2

I've been doing quite a lot of gardening in the past 3 years. There is a plethora of home gardeners and/or permaculture resources on the internet that generally like as much organic matter as possible. I some of that strategy as it's convenient at home to supply nutrients to plants without much work. But, I can't help but feel it's all sort of wish washy science. https://www.youtube.com/watch?v=KHZHy3_7PPE ^ I found…

Organic matter is mostly feeding the soil life. Sand, silt, and clay are where the minerals in food come from. The soil life makes them available to plants.

Re: How do plants extract nutrients from the ground?

#47

Post by tastyfreeze »

hinkley wrote: post #34
jspash wrote: post #13

I'm curious what HN thinks about the current trend of root washing when planting trees. From what I've read the science is still out and people tend to be split 50/50. The root washers say that by removing all media that the sapling was grown in will give the roots more "incentive" to move into the native soil and thus it will establish quicker. Whereas the anti-washers say you are slowing the establishment by washin…

I buy bare root plants because tree nurseries repot their seedlings too late, after the roots had already begun circling the pot. The worst one I ever saw had three layers of circling roots. I got it at my favorite froo-froo gardening center. I took it back and showed their plant buyer. He said that's normal. The fuck it is. Bare root plants never have this problem. There is definitely a tendency of trees to behave a…

I recently received a camellia sinensis (tea plant) from a nursery that was root bound. That wasn't much of an issue. The problem I has was the nursery was required to drench the soil in bifentrhin pesticide. First thing out of the box is a warning to wear gloves and keep kids and animals away from the root zone. No thank you. I have been cultivating an environment for the critters in my yard. I regularly have frogs, toads, birds and occasional deer and bear in my yard. No pesticides allowed! In this case I did wash the roots and repotted in my home soil mix.

Bare root plants do sometimes have issues getting started but I will only be ordering seed or bare root from now on.

Re: How do plants extract nutrients from the ground?

#48

Post by littlestymaar »

OrbitRock wrote: post #40
littlestymaar wrote: post #38

Earlier quoted context omitted.

Edit: this is wrong, see comments below. The correct answer is water though, not air. Air only accounts for the Carbon content of the tree, which is a big part, but still a minority. First, a live tree contains a lot of water (30-50%), that's why you need to let wood dry a lot before burning it. And there's something else: > Next we might look at water, but water is only made of hydrogen and oxygen, and the oxygen is…

I’m pretty sure the oxygen comes from CO2. Plant carbohydrates are made directly from CO2 in the Calvin Cycle. The Calvin Cycle is the source of all of the carbohydrate building blocks in the plant, and I’m pretty sure that oxygen from H2O does not enter the equation, just CO2 and some enzymes and cofactors. If so, the vast majority of the mass is from the air. (H might originate from water but its mass is pretty tri…

I stand corrected, I had somehow built-up a wrong understanding of it (looks like those high school classes are long lost).

But where does all that excess oxygen go then? (the O/C ratio is 2 in C but ~1 in carbohydrates).

Re: How do plants extract nutrients from the ground?

#49

Post by jarmitage »

thatcat wrote: post #25
jarmitage wrote: post #23

Earlier quoted context omitted.

Fascinating, thank you - I have some more questions if you don't mind! Was that your first degree or did you switch to this domain from something else? Would you care to name/recommend your degree program, and any key texts, for someone interested in following in your footsteps?

I got a visual comm degree, worked in video production for awhile, but decided to change fields. It kinda took a lot of time and set me back, but I prefer this kind of work. UC Davis has a good ag program, I think Purdue is highest ranked, Arkansas and NC state are good too. I went to UTK, it was not bad. The course work was just generic engineering stuff until junior level - then you get some really interesting biop…

Much appreciated, thank you for sharing!

I don't have a specific interest at the moment, but have been more curious about this area recently after getting into regen ag podcasts.

Re: How do plants extract nutrients from the ground?

#50

Post by thatcat »

hinkley wrote: post #42
thomasfromcdnjs wrote: post #7

Earlier quoted context omitted.

Oh that's such a cool company. I only recently got put onto Terra preta through my personal favorite gardener -> https://www.youtube.com/watch?v=DnTaWiO5Eso (he's funny lol) I'm going to try make my own ad hoc terra preta plots for fun too. Are you able to share any more information on your company? Who is actually buying this service? I feel like biochar is going to hit the main stream this year or next. Going to ma…

David has a guest video by a lady working above hardpan clay: https://www.youtube.com/watch?v=goUfl4x8URc Essentially all of the permaculture advice for breaking up clay appears to be failing on her hardpan, so she's started using broadforking, which is a sort of compromise between tilling and building soil from the top down. The speaker in this video is being a little more aggressive with the broadfork than most peo…

There are also "subsoilers" that you can pull behind a tractor that kind of lifts up the soil 36" deep and then drops it creating breaks.
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