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Perennial rice: Plant once, harvest again and again

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Re: Perennial rice: Plant once, harvest again and again

#201

Post by Buttons840 »

codethief wrote: post #195
thfuran wrote: post #138

Earlier quoted context omitted.

Atmospheric methane has a half-life of about 10 years and is well over 10x as greenhouse effecting as CO2. Converting atmospheric CO2 to atmospheric methane is less bad than releasing sequestered methane into the atmosphere but still terrible.

> Converting atmospheric CO2 to atmospheric methane is less bad than releasing sequestered methane into the atmosphere but still terrible. Sure, if this conversion led to more and more methane in the atmosphere, it would be terrible. In this case, however, the overall amount of methane in the atmosphere due to rice will stay the same, since it's a cycle.

It's all about cycle length. CO2 from shallow ground cycles into the air, then it quickly cycles back into the ground. The forest burns, the forest regrows. CO2 leaves, CO2 returns.

Fossil fuels are also a cycle. We bring up the fossil fuels from deep ground and a million years later that CO2 returns to deep ground. That's a long cycle, that's a problem.

Re: Perennial rice: Plant once, harvest again and again

#202

Post by doodlebugging »

onemiketwelve wrote: post #57

there's this perennial green onion mutant that I found out about from people growing it in China. Usually if you want scallions you have to harvest them very quickly, then the plant is kinda useless. But these ones, instead of flowering, they immediately offshoot new plants from where the flower would have been. https://en.wikipedia.org/wiki/Tree_onion

I found these walking onions a couple years ago planted a bunch of them along a hugelkulture berm that I constructed from downed tree trunks, decomposed wood chips, grass cuttings, compost and topsoil. They are definitely planted in the absolute worst spot right at the base of the berm instead of on it where the best nutrients should be. In spite of that I have seen them thrive in the poor soil. They do indeed form small onions at the tips of the stalks and those do tip over and root forming new plants. The whole thing is edible from the tiny onions at the top to the onion at the root. They also taste great so they have that going for them. If they can grow in the Texas heat with someone like myself tending them whenever he thinks about it then I think they will survive anywhere. I fully expected all of them to burn up in the heat but they have done quite well.

Re: Perennial rice: Plant once, harvest again and again

#203

Post by gus_massa »

Lunatic666 wrote: post #156

With perennial rice you lose the option to use the field for something else. Also timing the sowing with the rain is important. (Source: my wife's family are rice farmers in the Northeast of Thailand)

Here in Argentina I think we plant in the same spot soy and corn, or soy and sunflower, or other combinations. Each crop is better for the temperatures and rain of each season. So I also guess it's more effective to use a annual crop (that is actually only a few months in the field, not the whole year).

Re: Perennial rice: Plant once, harvest again and again

#204

Post by kleton »

chris_va wrote: post #18

(disclaimer that I manage a climate group, but not a rice expert) They touch on, but don't get into the details on one of the more interesting aspects of perennial rice. Rice fields are actually a huge emitter of methane. Depending on the accounting, they contribute as much to global warming as the aviation sector. The fields emit methane when flooded, the stagnant water gets oxygen depleted, and the biomass in the s…

But the flooding is also where most of the nitrogen fixation comes from. An environment that makes methane makes ammonia too.

Re: Perennial rice: Plant once, harvest again and again

#205

Post by ChatGTP »

chris_va wrote: post #18

(disclaimer that I manage a climate group, but not a rice expert) They touch on, but don't get into the details on one of the more interesting aspects of perennial rice. Rice fields are actually a huge emitter of methane. Depending on the accounting, they contribute as much to global warming as the aviation sector. The fields emit methane when flooded, the stagnant water gets oxygen depleted, and the biomass in the s…

Most rice fields I know of have water running through them ? Slowly but it’s not stagnant.

Re: Perennial rice: Plant once, harvest again and again

#206

Post by thfuran »

Buttons840 wrote: post #201
codethief wrote: post #195

Earlier quoted context omitted.

> Converting atmospheric CO2 to atmospheric methane is less bad than releasing sequestered methane into the atmosphere but still terrible. Sure, if this conversion led to more and more methane in the atmosphere, it would be terrible. In this case, however, the overall amount of methane in the atmosphere due to rice will stay the same, since it's a cycle.

It's all about cycle length. CO2 from shallow ground cycles into the air, then it quickly cycles back into the ground. The forest burns, the forest regrows. CO2 leaves, CO2 returns. Fossil fuels are also a cycle. We bring up the fossil fuels from deep ground and a million years later that CO2 returns to deep ground. That's a long cycle, that's a problem.

Isn't it the case that a lot of fossil fuels were biomass accumulated in a time before microorganisms had evolved to be capable of digesting woody plants and so are largely non-repeatable because the circumstances which can lead to coal are now narrower?

Re: Perennial rice: Plant once, harvest again and again

#207

Post by contingencies »

hinkley wrote: post #180
contingencies wrote: post #77

Earlier quoted context omitted.

With typical rice farming in Asia, you see manual transplanting of each seedling in to small fields by women and children. This is back-breaking work and extremely slow. I can't think of another crop both this widely cultivated and painstaking. Therefore, not having to do this is a huge win. China has a multitude of climatic areas. Some harvest rice once per year, others two or three times per year. Even within Yunna…

It might be dated information, but I'd heard 3 crops per year going back at least as far as 1900 (Farmers of Forty Centuries), but not that it was three rice crops per year. Instead a rotation of different crops in the same field. One of the tricks with rice is you can germinate it in one field, then transplant it to something like 4-6 times the same space to grow to maturity.

It's absolutely three rice crops per year in some areas. The transplanting strategy is the normal one.

Re: Perennial rice: Plant once, harvest again and again

#208

Post by AmericanChopper »

arghwhat wrote: post #144
wolfgangK wrote: post #139

Earlier quoted context omitted.

I really wish there was a name (that I knew of) for this logical fallacy of using precise quantities of meaninglessly confused categories. What do you think "farmland" is ? Our ancestors who knew how to raise cattle and farm cereals for millennia were surviving on the verge of starvation : why do you think that was ? Were they so dumb they'd rather die of hunger than convert some of their grazing pastures to cereal a…

Yes, some land is not suitable for agriculture. No, this does mean that having cattle is a neutral usage as each cattle requires agriculture to feed for 3-4 years before they are slaughtered. Yes, cattle emissions are largely from the food. No, this is not just grass that was already there and would decompose anyway - the majority of agricultural production is to feed cattle and would not be necessary without (the ef…

> Yes, meat protein is a great source of nutrition. No, it is not magically better than equivalent vegetarian nutrition.

It’s not magic, but the protein from animal sources is just scientifically better than protein from plant sources. If you want to compare the nutritional benefits of different protein sources you need to account for how bioavailable they are. Some plant sources aren’t bad, but none are as good as animal sources, and some of the them aren’t very good at all.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3905294/

Re: Perennial rice: Plant once, harvest again and again

#209

Post by colechristensen »

cmrdporcupine wrote: post #93
colechristensen wrote: post #19

Earlier quoted context omitted.

It’s hard to generalize but seed costs in the ballpark of 20% of revenue. That’s not counting tillage in preparation for planting, the cost of planting, or weed management which will be more difficult without established crops. In other words you can take a significant hit to yields and still come out ahead.

Without yearly tillage (or herbicide spray in case of no-till), weed mgmt is going to be tricky for perennial cash crops. It's certainly tricky for e.g. vineyards and orchards. I suppose with rice (or kernza wheat) you could use a selective broadleaf herbicide. Doesn't help with invasive grasses.

Herbicides are all generally sprayed when the crop is alive and growing anyway, there’s really no new challenge there

Re: Perennial rice: Plant once, harvest again and again

#210

Post by Sebguer »

thaumasiotes wrote: post #175
sampo wrote: post #168

In one of his videos in Youtube, permaculture farmer Richard Perkins said that mankind has 6000 years of agriculture, but has mostly concentrated plant breeding efforts to annual plants. We mostly eat annuals. (Plants that grow and die in one year.) But, he said, imagine what kind of perennial (plants that live multiple years) food plants we could have, if we invested similar 6000 years of effort to perfecting perenn…

> But, he said, imagine what kind of perennial (plants that live multiple years) food plants we could have, if we invested similar 6000 years of effort to perfecting perennial food plants. Like fruit trees and nut trees and whatever. Well, that's something we've already done. So I'd say we'd end up with the fruits and nuts that we have right now. What are we supposed to be imagining?

This is an obtuse read of the author's point, which is apply what we've done to fruit trees and nut trees to perennial staple foods.
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