From Acorns to Apples; Ancient Practices Revived with Eliza Greenman

The following interview was recorded for the Poor Proles Almanac podcast with guest Eliza Greenman, who joins us to talk about persimmons and oaks and their role in the future climate change-driven diet. Eliza works with the Savanna Institute and, as a researcher, uncovering lost selections of various tree crops. You can read her research at ElizApples.

Andy:

Eliza, thanks so much for coming on. I've been following you for a very long time. You are one of the only blogs that I've actually read whenever you post anything new. You're one of the few people that I look at and see new research happening, and it's just like every time I'm like, this is so beyond anything I knew, and like that doesn't really happen to me that often. So I'll be done singing your praises.

But for folks who aren't familiar with the work, you're involved in a lot of things. Now, when your name came up at some point in my life and like I started researching, like what you were doing, you were all about apples and pigs, and now you're into a million things. So first, I want to ask how you kind of got from apples and pigs to where you are today, and then we're going to talk about persimmons.

Eliza Greenman:

Yeah, Well, thanks for having me. I've been listening to the show for about a year now, and once again, your content at least scratches far more of the surface than most podcasts do. Like, you know, it's just glitter on like well-known tropes about all these topics, and you actually dig deep, so it's it's fun. It's fun to listen to. It's a bit like conferences for me these days. I don't go to really many conferences because it's just the same people saying the same thing, and there's nothing new or exciting usually. So thanks.

But okay, pigs and apples. How'd I get into them? So when I was 12 years old, I talked my parents into letting me have a pet pig that I saved my allowance for, and I'm from the coastal Virginia suburbs. Like I did not grow up on a farm. I think we had an eighth of an acre, so it took me a few years to get approval, final approval from my parents. But, like, and it was like the beginning of the internet, it was like, well, at least for me, it was like 1998. But I ordered a pig off the internet.

Yeah, that, like, took a Delta flight from Texas and landed and picked her up, and then I had a pig, and it was like a Vietnamese potbelly pig, and so, like, from early on, that pig, by the way, lived to be 23 years old and died to died two years ago. But early on, I had this fascination with pigs, and like, I just knew so much about them. It was like one of the things I read about all the time and so it was. They've always just been a fascination of mine, and in the back of my head, I'd never want to have another pet pig. But I had just been thinking, like, hmm, how could I, like, stretch this itch, basically, and like keep learning about pigs and see where I end up?

So, I have a degree in forestry, and I worked all over the United States and parts of the world after obtaining this degree and parts of the world straight after obtaining this degree, and I just learned that I did not like forestry as it was.

I didn't like the community or the culture around it, especially in the South. I didn't like the idea of raising trees for monocultural applications for in-use products that might be toilet paper, you know, or something like that.

And so, I slowly, and I guess I won't get into this much, cause I do talk about this a lot is I started to transition out of pulp or, you know, timber trees into, like, this realm of non-timber forest products trees, and so I started learning everything I could about the persimmons and the hickories and all the plants, identifying them and trying to figure out if they're edible or whatever, because if you're working in the forest, a lot of time generally, and so then that like transitioned into me living on an island that was covered in apples and they didn't really have a timber product and this is in Maine, and it all just made sense.

It was like, wow, this is, you know, a form of this is this is actually a form of forestry, but it's for food production, and like they're bright and colorful and like so much better than, and like people love it, like everybody loves apples, and there's nobody like strapping themselves to a tree to save an apple that, like you know, is getting pruned. Yeah, it was like a whole cultural shift for me, and also like a molecular shift as well, like my whole body was just like this is it, this is where this is where you need to be, and it was an instantaneous passion that I hit. That's also like a curse in many ways. But uh, yeah, uh, to bring back pigs into the equation, I started reading I mean, I've read everything I can just about apples that's been written prior to, let's say, 1950.

I just started to learn that, like, the genetic origin of apples was in Central Asia. So I like I saved up, and I went, and what I found there was they have like apple forest, and the apples are also growing. They're like walnut forest too, and there's like cherry, plums and pears. I mean, it's just like a purely natural native fruit forest and net forest, but it's managed by people with animals, and I just started to see the whole sustainable loop of animal inputs and services meets final products and like human and like derived human nutrition and all of these things, and so that's when it was like the pigs came back into the picture and it was like, okay, there's, you know, this is, these are Muslim countries like they don't manage with pigs, but I happen to know a lot about pigs. So that's when I like shepherded them into my new, my new realm of trying to wrap my head around more holistic, cheaper ways of managing orchards for both high quality, like meats or animal products and fruits and nuts and wildlife, basically, or habitat.

Andy:

Yeah, and how did you get into persimmons from there?

Eliza Greenman:

Yeah, so persimmons I first got into when I was working for Louisiana State University. I was doing bottomland forest research, where you're wearing high waders, you know, and watching the gators, yeah, dangerous and hot, but in the bayous, watching water moccasins swim by.

But uh, so I started to see persimmons like all over the place, and then I started to read about them and started to eat them and again, like I spent so much time in New England, like pretty soon after that, and like I spent so much time in New England like pretty soon after that, like the next seven or eight years, that persimmon sort of fell out of my realm.

But once I moved back south and started to see them and then started to get like I do some consulting, and so I got hired to do a bunch of persimmon research for somebody, and just it completely opened my eyes up to how valuable of a tree this is and how it's almost completely unnoticed, like in terms of it's not only like it's human benefits but also it's incredible animal benefits that uh, yeah, so I would say I really kicked that into high persimmons into high gear, probably like two years ago.

Just trying to think about from, like feeding, from a feeding pigs perspective, like okay, like what crops will drop for have the longest drop window, and sure, apples are one, pears are another for persimmons really, pecans are another, but persimmons as you know, depend. You can mix and match and get, like, September through February drop, when you're most scarce for food; that's how it just kept moving up the list of important everything I learned.

It's just like, wow, this thing is really incredible. That's how I got into it.

Andy:

Yeah, persimmons are a wild fruit. I'm from New England, but I did spend a little bit of time in the south, and I did see them occasionally. But also my family's from Italy, and they're very common, obviously not the American persimmon, but persimmons in general. So, like, I was like, oh, I know what that is like. I know kind of what it tastes like. Yeah, it's, it is a really unique native fruit that doesn't get a lot of attention.

One of the things I have read about it was that in terms of caloric content, it's one of the densest fruits in North America, and it's like you said, drops late in the year, and it's a big tree, too. It's a big, you know massive amount of fruit that comes out of one single tree versus a blueberry bush or even like a chokecherry or something like that. So you're getting benefits of it having like a massive fruit as well as like having this massive tree itself.

So one of the things that I think you have turned me on to more than anyone else is the potential because of some of the diversity that exists. You know, we're talking about it being a southern fruit tree, but it actually does really well in the north, and I think, especially with climate change, persimmon is going to be one of those fruits that we are going to rely on very heavily 50 years from now. So I'm curious about your thoughts on its movement going north and a little bit about that genetics.

Eliza Greenman:

Yeah. So I'm going to launch into a little bit of a background on persimmons because we've been doing a lot of work in this. Also, I work with Savannah Institute currently on a persimmon breeding project, and so a lot of these insights I'll share are from that work and that we have done and will continue to do. But so there are two types of persimmons. Well, that's not completely true, but when we think of an American persimmon, there are two main types. There's the Northern American persimmon and the Southern American persimmon.

The difference between the two generally is that the Northern persimmon is more of like an orchard tree, so it grows to be like 20, 25 feet tall, the fruits are generally larger, and there's this crazy phenomenon that happens with the northern persimmons, where persimmons are normally dioecious. So that means there are male and female plants, as you know. So females are the ones that fruit and they need the males to flower and to be pollenized by bees and whatnot. But in the 90s, so, and I'm going to refer to these as 90 and 60. And I know that's going to confuse everybody, but the northern persimmon has 90 chromosomes, which makes it a hexaploid, and the southern persimmon has 60 chromosomes, making it a tetraploid, and I'll get into that in a minute.

Yeah, but then the northern 90 has specimens that are monoecious, where there are male and female flowers on the same or reproductive structures on the same tree, meaning that they're not, you know, they don't need some male because it's already, it's already on the tree and that's like one of the major tenants of domestication for a lot. If you look at like a lot of the crops that have made it into the human realm, usually they're monoecious. Very rarely do you see a crop like dioecious seems to be considered more so undomesticated or wild. It's not completely true, but like with mulberries, for example. But mulberries are also leaky in their sexual structures. There's that.

And then there's the Southern persimmon, the 60 chromosomes. That is a much taller tree like it can be it's more so a timber tree, or it can be a timber tree. They're in the ebony family, so the wood is super valuable. Well, it used to be anyway, like when they made golf clubs out of ebony and steering wheels, and the fruits are smaller and generally drop later in the year. Then where the 90 northern drops earlier, and that's, you know, because of their climates they're adapted to, like the fruits in the south aren't going to hit like a crate, you know they're not going to hit crazy cold for a while and so they can hold on to their fruit structures for, you know, as long as they want, basically, whereas in this in the north, like they got to ripen those fruits fast in order to rely on some sort of dispersal.

So we're primarily working with the 90 chromosomes of northern persimmon and trying to push the boundaries northward to see where, basically, in making some selections, we've sequenced the 90-chromosome genome, our persimmon genome, which turns out to be incredibly difficult. We received assistance from a sequencing company called Pac Bio, along with Hudson Alpha, which is a non-profit sequencing company.

They're like an incredible genetics organization, and they did it. They, I mean, we raised a bunch of money, but they did it for us to try and start unlocking the mechanisms behind. Where are the genes basically that control cold, hardiness and can we select from those from like seedling stage, you know, once at first leaf out?

In order to really speed up persimmon breeding, because at this point, if we plant it from seed to fruit, that's like six or seven years, you know. And so that's what your cycles are looking like, and we're this, you know, after our first cycle, it could very well become, once we figure out what the markers are, it could very well become, once we figure out what the markers are, could very well become like two to three years between picking, basically picking the right parents that have those cold hardiness genes. That then we can get work like making all the crosses to ensure, or try to ensure, that they've got the stuff we want yeah, but they're still pretty cold, hardy, right, like even as as they exist today.

Andy:

I think, because we think of persimmons as being a southern fruit like they can handle New England today.

Eliza Greenman:

They're plenty hardy generally, like if you buy American persimmon from an online nursery and they ship it to you. It's gotta live. Yeah, the main issue is ripening in time. So you know, if you've got like a heavy, heavy frost in late September, you're bumping up against, um, basically like the viability of if you're gonna get fruit or not, so that's the first thing. And like it wouldn't hurt to just like have persimmons and waiting, you know, for like those warm, those late frost, warm years.

We're also talking to people like Buzz Ferver, who lives in zone 4A, Vermont. Seedling persimmons tend to be less hardy, so we're testing first who has antifreeze in their veins, basically planting from seed and then going from there.

Andy:

Yeah, there's some really interesting stuff going on with the genetics. You also have been digging in pretty hard on, like the ploidy nature of the genetics of the persimmon. Now, for somebody that's not like a biology background. Why is the ploidiness a big deal?

Eliza Greenman:

So, in general, when you have sometimes, okay, so my default language is usually Apple, so I'm gonna go back, I'm gonna switch over and tell this in Apple. So apples are diploids, meaning they have two sets of chromosomes, and so when there's a doubling event, a diploid goes to a tetraploid. Usually, what that means is the fruit gets is huge compared to the diploid, the leaves are huge, and sometimes the plants are huge. It depends, but apples, generally, the plants are a little bit stunted, and that probably has to do with, like, the massive fruits that they're now producing. A normal, usual one will usually mean the fruits are larger.

Andy:

You also see this in all the blackberries coming out of Arkansas or the ones that are exactly the size of golf balls.

Eliza Greenman:

Those have been chemically altered to go from diploid to tetraploid, and also, like strawberries, they are at octoploid status these days, and it's all human interference to just try to get things larger.

Andy:

Yeah, there are some chemicals you can use. I believe that can push genetics to go into politeness, right?

Eliza Greenman:

Yeah, so the traditional chemical used is called colchicine, which is super toxic and hard to deal with if you're not like in a lab setting. But then they started to find that there's this one herbicide called oryzalin; I don't know how you say it, O-R-Y-Z-A-L-I-N, and that was causing doubling in a lot of the plants. It's like a pre-emergent herbicide, which is hilarious to think about, like how many superweeds might've come up as a result of like crazy doubling, because also like what's that invasive, like almost bamboo-like in New England.

Andy:

Japanese knotweed.

Eliza Greenman:

Yeah, so Japanese knotweed. I read this crazy paper about how it's doubling and then reducing back as its main mechanism for invading new areas and being able to be successful, and you know, increasingly colder or wetter or whatever.

It's just like constantly, and it's probably some of it has to do with people pouring herbicides on them or, God knows what, or the cold weather. So, outside of human manipulation, it's basically like something that happens randomly in nature. That often is the reason for successful establishment beyond its native boundaries.

Andy:

Yeah, I wonder, you know, getting on the invasive species thing, you have these invasive species come in, and they're usually not invasive right up front like they usually settle in, and then it seems like after 20 or 30 years there's like this sudden change and I wonder if that has to do with how they're reacting because a lot of ploidiness comes from species trying to create, to exploit a niche, right. So I wonder if that plays into some of that, into that, how non-natives can turn into these invasive species to these invasive species.

Eliza Greenman:

Yeah, it could. I mean, I also, like, this is only on topic for this, but I read this hilarious paper about Japanese honeysuckle and how cardinals have started prioritizing feeding on the red berries because it makes them redder, and the chicks dig the deep red plumage and so like it's totally become like a sex icon sort of thing, that that's like well, that's how it, you know, that's how this thing is so successful.

Andy:

It's totally turned Cardinals into like the Kardashians; there's a really good pun in there somewhere about cardinal Kardashian, it's there I don't have it right now off the tip of my tongue, but yeah, it speaks to the fact that a lot of this stuff is so complicated and like we can, we can leverage what we understand as much as we can, but like we also have to be like really observant of the fact that we many times don't really know what we're dealing with.

We think we do, and then we learn a little bit more like, oh, actually, we didn't, and then we think, for some reason, that's the new goalpost, we've made it, we understand this now, and there's nothing surprising. We're going to learn in the future. But I do want to talk a little bit more about this genetics because one of the things that I know you've been looking into is whether or not there's been selection happening or there was selection happening by Indigenous people with persimmons and the way we see them spread across the landscape.

Eliza Greenman:

One of the things is, we know that the Northern 90 chromosome persimmon exists in the Southern 60 chromosome range in numbers, and so, like it's in Kentucky, it's in Virginia, it's in North Carolina, and I have a feeling that if we were able to go out and map these trees, we'd probably start to see traditional indigenous pathways arise from it. But one of the things that alone, though, seeing the 90, like representing itself in this southerly range within a certain line, itself shows that there has been selection. And then just doing the genetics on these trees to figure out, like are they related? Like, what are they sharing? What are they sharing? Like how did this evolve?

The first 90 chromosome persimmon was written about by white people in Alton, Illinois, which is in southern Illinois, and so, from there, seeing where they went and who's related to what, and is it like a great, great, great grandparent or whatnot, so we should be able to tell that, which, in a lot of our breeding work, like it's super important from like a royalty structure, sort of thing of like you know, it's the constant question of. Yeah, okay, we are actively trying to work with wild crops, native crops that had a heavy placement in indigenous culture, and so all the good genetics we're working from essentially were very likely selected by indigenous people, and so, like putting that in as the ground floor of a royalty structure for anything that we come up with in the future that you know could help push the range, it might turn it into an industry, something like that.

Andy:

At first, when you said royalties, I was thinking more like genetic lineage, like my dog is a duchess because of her birth certificate, and I'm like okay, like I see where you're going, and then you flipped it on me but like, no, that that makes a lot of sense. It's something I don't think that gets a lot of attention, and obviously, it's like this really uneasy ground, as somebody who does sell plants and focuses on native plants, about like what is my responsibility and what should I be doing in terms of like honoring that work that's been done in the past and like giving back financially for that work that makes it so I can sell sunchokes or you know whatever.

It's funny a couple of years ago, we actually had a guest who had researched the Cherokee and their involvement with honey locusts, which I know is something we've talked about in the past, a little bit off the air and like it's just, it's wild because we, we, we forget that like these things were still in transit. These were all plants that were in transition because nothing is really static that I try to imagine, like, what a persimmon would look like today if white people had never shown up in North America, you know what I mean, like where they would be today if they had continued that genetic research that had been going on.

The same with pawpaw, hickory, American chestnut, and even white oaks, and red oaks. They were all something that was probably managed in some capacity, maybe oaks less because of the diversity. That would have been a really, really tough one, I think. But yeah, there's just like it's really, I guess, like grounding to think about, like how small this moment in time when we're trying to do this stuff bring these crops back is in the longer history of how they've been stewarded. So giving back, I think, is really great if you can do it.

Eliza Greenman:

That's the goal.

Basically, to create silvopasture systems that are adopted by a wide swath of the United States, that help not only give back from a monetary perspective and also from a signatory perspective on genetics but also carbon sequestration, growth of agroforestry, adoption of agroforestry. Persimmon seems to be the golden ticket in that realm to me.

It's just got it all, the number of calories it can put out and especially if you're working with, like pigs, like you were talking about, in terms of what they can, how they can convert it, you know, sugar into a protein, basically, you know, and I think that's really like. I think it's important to think about these crops as human food, but also the role that these crops would have in supplementing, like monocrop corn, is something I don't think we should dismiss, and that's, in particular, around like nuts, like hickories, are a really phenomenal nut to eat. They're a pain to process. Give them to cattle. Give them, you know, give them to something that can eat them.

I don't, I don't actually don't know much about cows. I've never worked with cows, so maybe that wasn't the right example, but you know the idea of, like, all right. So, instead of trying to make, trying to restructure the entire American diet, how do we do these things in a way that's most accessible and can cut out as much of the bad stuff of our diet without having to necessarily make it functionally different? So I'm interested in your thoughts about, kind of, where the persimmon fit in the American diet in a hundred years, in this climate, not an apocalypse situation.

Eliza Greenman:

From a nutritional standpoint, persimmons are #1. Well, as you said earlier, they are they're the most nutrient-dense native fruit to north america. So see ya, pawpaw. But uh, they also like they have 31 sugar. They have 19 amino acids out of 20, so they're almost a complete protein, which is a real shame, because if they were like we would be, you know, see you soy, that kind of thing. But yeah, and then they just have tons of macronutrients, and I mean overall, like they're an incredible carbohydrate, and a lot of times, like animal diets or human diets are broken down into, yeah, carbs versus protein, and it's always like carbs are villain, you know, seen as villains and all these things, but like it's where a lot of energy is. And so if I were to fast forward a hundred years and look at the American diet on persimmon, persimmon would be an additive in anything that tastes good, you know, like it would be sweet to completely use it as a sugar substitute, like granulated.

The American persimmon is currently weird to work with. If you heat it in any way as a raw product. If you heat it, it starts to turn solid in a way, and the tannins sort of come out, and so you start to. So there's a lot to work with. But I'm sure I mean hell, we've worked a lot more on other crops, on other annuals, to get them into our diets than this. But yeah, just like an incredible energy source, that's probably a superfood. It would be cool to see, like in the grocery store, those cottage cheese cups that have persimmon pulp on the bottom rather than pineapple. Yeah, but also just the animals. It makes so much sense for them to eat persimmons. I don't know why it's not happening more, yeah, when, with how quickly they grow.

Andy:

I mean, like, if you're going to do a silvopasture, that should be by far one of the first crops to consider because the how quickly it grows, you know, if you're going to plant like a hickory tree, thinking like calorically speaking, before you're getting the same harvest as you would out of a persimmon, you're going to be waiting 30, 40 years. I mean, they'll produce but not, like, not even close to the volume you'll see out of a persimmon tree, right? I've got two in my front yard.

They're 25 feet tall, and I think I planted them four years ago. I mean, they were like first-year whips, but like that, that's what they do. It's just like if you give them everything they need, they just take off, yeah, and they're also like, what, what is it?

Eliza Greenman:

So there's a certain class of plants that I really love, and I basically call them, like they're part of a disturbance ecology. And persimmons are right in there, where they're fire-adapted. They will, like you know, say a deer comes along and eats the whole top of a young tree. It'll send out, like a sentry tree, I think, as a defensive compound, like they'll start to send out runners in order to try and protect the original, like the main tree, from browse.

Andy:

Yeah.

Eliza Greenman:

Yeah, they're just built to survive, and they can handle all the soils and water too, and water, Right? So, like in Virginia, one of my properties is a wetland, like it's a major seasonal wetland and every place where I have like a micro-topography of, like, say, eight inches taller than the rest of the persimmon coming up.

Andy:

You don't have to spray for bugs, either. You mentioned deer, and honestly, I think a deer hit mine maybe once, but they don't really like velvety leaves. They're just not really, or at least here, the deer don't seem to want them.

Eliza Greenman:

Oh, here they do. I have an epidemic of deer.

Andy:

Maybe it's because they just don't know what it is around here because they're not common.

Eliza Greenman:

Yeah, that could be.

Andy:

I've seen a nibble here and there, but it's funny. I have some quince in the backyard, and they get destroyed by deer. They have very similar, like kind of thickish leaves, but they don't touch the persimmons. So maybe I'm just lucky; maybe my deer are just not evolved for that.

Yeah, I think mine probably have it in their microbiome gut. Every now and then, they just get a persimmon craving, which I can understand.

I know this has been one of your main interests, and I do want to talk a little bit about oaks as well because I've been getting into a real rabbit hole on oaks lately, and one of the things I've actually been thinking about is, as we try to think about these like novel ecosystems that are going to be coming up because of climate change and what, what our responsibility as land stewards in terms of like facilitating migration for species that move very slowly north during, like this impending climate, you know, whatever you want to call, call it, a lot of species that can survive those colder climates don't travel fast enough.

You're going to have species traveling and then like trying to create kind of new ecosystems, because there are new places with other plants that also ended up kind of in the same spot, and I've been trying to think about like all right, what, where does a persimmon fit into that kind of ecosystem around here? I feel like it would do really well around white oaks. I think that would make a nice sub-canopy tree for a white oak, oak-hickory forest kind of area, and then you get the best of both worlds. But to get back to you, you were recently in Portugal doing fun stuff with acorns, which I'm incredibly jealous about. You must have just had a field day with the dehesas and all that kind of stuff.

Eliza Greenman:

So I got invited to attend a conference on edible acorns, and it was in. It was on this, right on the line of Spain and Portugal, and apparently, every two years, it goes between one country or the other. I love nothing more than a completely nerdy tiny niche of a conference because that's when people come out of the woodwork.

Andy:

And so, yeah, I attended this conference would.

Eliza Greenman:

And so, yeah, I attended this conference and what was so interesting to me is, yeah, in Spain and Portugal, you know they have these in Portugal it's called Montado and Spain is called Dehesa which are these oak savannas that through human manipulation over time, especially over like the last 120 years or so, have become pretty I mean pretty decently, like two species for silvopasture, like across vast areas of land and where, you know, Jamon or Iberian ham is produced, the most expensive ham in the world because it's finished on these, in these savannas, on acorns.

But what was so interesting to me about this conference was they were looking to move past that, like, okay, so we have succeeded in the silvopasture realm of oak trees, but now, like, how do we take them further and reintroduce them into human diets? And I think that's like it was such a valuable thing because it's totally where my, like, a lot of my research has been. Like, okay, well, sure, I can create these crazy orchards that drop, for you know, from May to March, and all that matters for me right now is that I can get animals to eat the drops, but if I can get humans to start eating, you know, can I? If I can get humans to go through this thing as you pick or something, then it's going to have a lot more value added to it than just the meat. But, like, having an economic strata of just animals, I think, is actually a pretty good way to change agriculture in certain respects.

So I learned so much at this conference, one of which is like, I guess I'll go into three rounds, so we'll do fruit exploring, and then we'll do nutrition, and then we do like, I don't know, I'll free wheel it, but like in these niche crops, like there were quite a few people there that would be considered fruit explorers or I, I consider myself a fruit explorer of like just people that go out and look for improved or crazy in some way fruit or nut producing tree to then like try to bring it, save it, put it back into circulation, giving it a job of some sort.

At this conference, I learned that there are tons of people who like going out, not tons, let's say a handful of people going out into Spain and into Portugal and looking for, like very low tannin acorns, acorn producing trees, and from there, like propagating them and trying to get them out. And because low tannin in acorns is like the moneymaker, there's a lot of people out there that leech, and this is happening there too, where like acorn flours being made from high tannin acorns that have been leeched but ultimately like that processing system is expensive and cumbersome and doesn't really meet current like consumer levels. To justify the cost, you end up seeing it like in the United States. You see it like in Ashville, you know, or some other place that might be like that.

Like if I were, somebody was like, “Hey, Eliza, where do I buy acorn flour?” I don't know, but I guess I can tell you how to make it. But anyway, finding these low-tannin acorns is sort of like. The next era of how to bring these to the human consumers lines is the Spanish government is basically writing regulations for what trees can be propagated and planted out like it's you can't do it willy-nilly like you can in the United States like they have to evaluate and all these things before they can give like permission of these fruit explorers or whatever this is sort of new of the fruit explorers to like reintroduce or introduce these low tannin acorn cultivars. And one of the guys there, whom I'll remain nameless, was telling me that the Spanish government is actually stealing these cultivars, that he's been finding and patenting them and then fast-tracking them into the release, into being planted.

And so, like this, these, like fruit explorers, are in huge need of somebody, a genetics lab or something to do like quick genetic thumbprints of everything they're finding, in order just to save it from getting completely co-opted by the Spanish government, and I'm really thankful that I don't think anything like that would ever happen in the United States because they don't care.

Andy:

I mean, I guess that is the silver lining to the fact that our food system is entirely built on mono-crops.

Eliza Greenman:

Right, exactly, but the thing about so the species that were mostly talked about were Quercus ilex, or Holm oak, and Quercus suber, or cork oak, and there's low tannin specimens of both, like good, healthy handfuls of specimens that have been found, and at this conference I actually got to taste a bunch of them, fresh and dried, and you know I've tasted similar or lower amounts of tannin in the United States. It was actually really refreshing that finally, like I guess due to our, like North America's, vast diversity of oak trees, we have them.

It's just a matter of having to find them. And it's unfortunate that we're at the point where we have to find them now because, like 120 years ago, like the TVA did all sorts of contests for this and like they found, you know, the lowest tannin white oak, the lowest tannin chinkapin oak, like the lowest tannin chestnut oak, like they were finding all these specimens that had been propagated and were getting planted out, and now they're, you know, Taylor Malone and I found the lent white oak, the winner of the white oak group, that's still alive and I've had a hard time grafting it, but I did get somebody to graft it for me who's got it in a greenhouse currently, and it's doing fine.

The beginnings of this conference were just like a man. If we could just somehow get people to look and eat like taste acorns, we could really get somewhere. For instance: I grew up close to Williamsburg, Virginia, and colonial Williamsburg has tons of corcus virginiana or live oak. It's an evergreen oak and, like most of those acorns, have very little tannin, like perceptible tannin compared to what I was eating. So it's just like I feel like the pursuit of low-tannin acorns is a bit of the Wild West that I would love to see start to take off.

Andy:

Yeah.

Eliza Greenman:

I would love to see somebody put up a million dollars or something like that to find it.

Andy:

Yeah, I love the burr oaks, Quercus macrocarpa. Biologically speaking, there is no difference between two different types of burr oaks, but there's like a swamp variety that just like gets significantly bigger and has low tannins. That is really, really appealing to me, but it is not anywhere close to even getting involved with harvesting or trying to find ones that are good. I don't know if you've ever gotten to mess around with burr oaks, but they're if you've ever even seen them. But they're ridiculous, and they're huge.

Eliza Greenman:

Yeah, I was sent some this winter to grow out from a friend, and it's giant. You know, it's like the actual acorns, like a golf ball.

Andy:

It absolutely looks fake.

Eliza Greenman:

Yeah, and it's so much, much, I mean it's just so much bigger than any of the acorns I tried in spain and portugal.

I talked about burr oak with some Portuguese people, and they said that actually, like after the war, the United States sent over a ton of burr oak into Portugal, and so they actually have some, but like nobody's been, they're like, oh yeah, but they're all bitter, and I was like sure, maybe you should just do an assessment. Some burr oaks are bitter, but a lot are really quite nice. You know, like, comparatively to like red oak, they're outstanding to me.

Andy:

That size, though, is like the thing that should be like. Not that you can't process small acorns, but, man, I think about how much easier it would be to scale production with something that much bigger that produces fewer, bigger nuts.

Eliza Greenman:

That seems like a no-brainer to me, yeah, absolutely; I mean, you see it, we see it with chestnuts, like Chinese chestnuts, like people only want the big nuts, and I don't know if that's just like an ego thing or an actual like picking. You know it is a lot faster and more economical to pick up big nuts off the ground than small ones. Yeah, so yeah, I completely agree, and I wish that it's not going to happen in Savannah, at least. As you know, we've already got our crops that we're working on. But it would be so amazing for somebody to actually pick this up and work and I would be happy to share any sort of connections and whatnot.

Andy:

Yeah, and that's the hard part is like it does take a significant investment to really build an infrastructure, and you know, I hope so. I agree with you. I think in terms of like making acorns a crop food for humans would require something like the burr oak and some intensive research going into it. I was also thinking about this other piece with acorns A friend of mine brought up to me about the actual processing practice. We're talking about leaching acorns. Most people put it in water, either standing water or running water. But also there's an interesting history.

If you look at the process of leaching those tannins in different parts of the country, different indigenous groups did it in different ways. One of the ways is like slaking, which I'd never really thought about, like how you might nixtamalize corn, and a friend of mine tried it, and she said it was actually quite good, and there was like a noticeable difference. So I wonder if that was influenced by the types of acorns, like the types of oaks that were growing there, which there seems to be very just like, and of course, I'm just like reading research papers and trying to connect these dots. This is no scientific consensus or anything, it's just me being like hmm, that looks interesting that there does seem to be some overlap in what the main types of oaks are in regions and how they were traditionally leached. And if we started incorporating some of those thoughts into the species we're picking, how might that change that flavor profile and make it a little bit more accessible?

Eliza Greenman:

Oh, that's fascinating. I've not thought about that really much. Like the slaking is new to me, but it would totally make sense. You know, if you're looking at Indigenous like old pictures of, like California, Indigenous like processing acorns, you know, you see all these holes like in rocks and such. But, like, those sorts of rocks don't really, you know, they're not ubiquitous like across the United States, and we certainly have like way more species, you know, like that are growing in, yeah, places where there are no rocks like at all. And so, yeah, just thinking about how processing might have happened if it wasn't pounded or basically like this in the same vein of a gristmill or something along those lines.

I met a man who's been on a lifelong acorn adventure, figuring out how to eat them. He's Basque, I believe he's in Basque Spain, and he was saying that he was like, okay, well, I've got these tannic acorns near me.

The thought was, what other, what are analogs exist that have this much tannin that is actually consumed by humans, and how are they doing it? And he was like, aha, olives are terrible, and yet through fermentation, they turn into these delicious products. And so he I think I'm going to write an article about this because he's going to announce his workshop, I think, in April but he has figured out the methodology behind fermenting acorns so that the meats are delicious and the amount of tannins they have, like it just matters how long you soak them, um, and change the water, essentially, but it is like soaking, you know, you're just cracking them and it is just soaking for however long in a brine and man, they're fantastic. And that, to me, like completely caused me to have like an aha moment.

If we're going to talk about livestock, they're going to cause them to lose weight. You know, yeah, it can be a toxin or an anti-nutrient. So this idea of picking up acorns and putting them in barrels and fermenting them in brine and having them as a late winter feed if you need to do, or something super valuable to me, yeah, and also potentially as a human food too.

Andy:

Like acorn silage.

Eliza Greenman:

Yeah, exactly, I mean, that is certainly something that I think about a lot.

Andy:

So I mean basically yeah, that's what you're doing is processing in a similar enough way.

Who knows, like by the coast, potentially, like you know, eons ago, like maybe there was like saltwater brine acorns going on, and we just I mean, I'm almost positive, I've got to imagine like on those islands in Georgia yeah, like or you know you're talking about like spain, but like that iberian peninsula in Italy have so many different or similar characteristics, and you know, acorns are pretty, maybe not today, but historically were considered or understood as more of a food and especially given the way they managed olives, I can't imagine that they didn't at least try.

Eliza Greenman:

Right, it's just not written about. And part of that I also learned watching all these presentations. I kept seeing photos in these like, you know, people that speak no English. Like I kept seeing photos of american indians like harvesting you know all in their acorn culture, like it. Just presentation after presentation and I was talking to one of the Portuguese guys I was like what the hell, why don't you use your own photos, like your own historical photos? And they're like oh, they don't exist because eating acorns acorns are a poor food and so like there's so much shame around acorn culture and like subsistence living that like nobody wanted to be photographed engaging in any aspect of it whatsoever. And so now in like our renaissance that we're trying to bring back to switch this crop over to humans, like we've only got you guys over in California to lean on.

Andy:

Wow, it really is one of the most interesting things, I think, with this podcast and like getting into some of the research we've done. You start digging into these like rabbit holes of like very basic, fundamental how did people live a thousand years ago? There's just so little, despite it being the most common information, because it was so common that people didn't think there was a reason to write it down. Why would you write down what you do every day, like how is that going to change? And obviously it did, but it was just so common knowledge that that no one cared to make sure that it stayed known. Now we got to do the legwork of trying to rediscover all this stuff.

Eliza Greenman:

Yeah, recreating the wheel.

Andy:

It's fun at least.

Eliza Greenman:

I mean, I guess that's a hobby, yeah, so.

Andy:

Eliza, for people who want to know more about what you're doing, watch you go on these wild trips. When you were looking up the, the what was it— the black locust for cultivar the shipmast?

Eliza Greenman:

Yes, the shipmast.

Andy:

I've done a lot of research on black locusts, and I'd never heard the term shipmast black locust until you were talking about it.

Eliza Greenman:

They are worth paying attention to. Well, I have a blog that I poorly maintain. Maybe you get an article or two a year out of me on it, and so that's Eliza Apples e-l-i-Z-A-P-P-L-E-S dot com. And then, yeah, the Tree Crop Improvement Program, which is what I work with at the Spann Institute. We're hopefully getting our own little website section where we'll publish the black locust improvement report that me and Taylor Malone wrote, which are probably the nerdiest, uh, specimens available on the internet for resources. So those are coming. Those will hopefully come out sooner than later. And then, uh, yeah, I guess you can follow me on Instagram at Eliza Apples.

I’ve started to downsize a bit on the social media aspects of my life.

Andy:

That's fair.

Eliza Greenman:

Yeah, just because I'm like fully employed to do this now.

Andy:

So it makes it a lot easier.

Eliza Greenman:

Yeah, exactly. I don't have to sell it as hard. Yeah, I'm happy to. I'm generally happy to talk about these sorts of things if the conversation is productive.

Andy:

Yeah well, thank you so much. This has been phenomenal. I have a million things I'm going to go research after this, so hopefully next time we talk we'll have a lot of new exciting developments on burr oaks to talk about.

Eliza Greenman:

Yeah, one quick thing. It's circling around in my mind: Have you read the paper about large acorns in the United States, the theories around how they were dispersed, or why there's a clear correlation between larger masting oaks?

Andy:

No, you're going to change my life again.

Eliza Greenman:

Yeah, I'll send you the paper.

Andy:

Okay.

Eliza Greenman:

They're not saying humans at all, which is ridiculous, but they are saying that the size of the nut means it's got a larger lunchbox to eat from, and so, larger oaks, larger nuts, and oak species or specimens tended to travel better, and they were giving no indication of how. Yeah, you know, but I have so many questions because it wasn't. It wasn't a passenger pigeon.

Andy:

Now I need to know about that, but yes, this is what happens every time I talk to you: I end up finding about 10 different things I need to research. So thank you so much. Your work is really valuable. I hope you know you keep doing it because we all need it. And yeah, we'll be in touch soon.

Eliza Greenman:

Yeah, thanks for having me on, look forward to hearing it in all of its glory.

To listen to this interview, tune into episode #169.