Andean Walnut

[agroventuresperu]

Hi forum,

I just received some seeds this week of Juglans neotropica. I've never propagated this species or any other species of Walnut before. Does anyone here have experience with this species?

I was wondering about the best way to pre-treat the seeds. I was thinking about using a bench grinder to slowly sand away the vast majority of the endocarp all over before revealing the seed coat in one or two spots, and then soaking in water for three days with water changes. The bench grinder idea is my own. The three day water soak idea is from a forestry publication in Spanish from Peru. I was thinking the three day soak might be too long if I'm doing the sanding with a bench grinder. The other doubt is if I sand unevenly, would that cause problems with germination since the seed might swell inside but then be subjected to differing gradients of pressure along the woody endocarp?

[Galatians522]

There is probably lots of research out there on how to germinate black walnut. Nice find, by the way!

[agroventuresperu]

Yep. I assumed they were equivalent seeds.

[nattyfroootz]

I germinated black walnut easy just moist potting mix. Might be as easy but can't say, good luck! Oscar at fruitlovers might have some insight

[Vegan Potato Man]

I germinated black walnut easy just moist potting mix. Might be as easy but can't say, good luck! Oscar at fruitlovers might have some insight

Oscar said the shell on Juglans Neotropica is substantially harder than Juglans Nigra

[agroventuresperu]

I germinated black walnut easy just moist potting mix. Might be as easy but can't say, good luck! Oscar at fruitlovers might have some insight

Oscar said the shell on Juglans Neotropica is substantially harder than Juglans Nigra

Thanks. I've decided that I'm going to use the bench grinder to steadily shave away the hard woody endocarp. I won't go as far as the seed, because I know there's a risk of infection when exposing the seed sometimes with species like this. I'll probably soak for a couple days, but no more than that. The idea is to remove the vast majority of the woody protective layer around the seed and to try to get these to sprout sooner than they would otherwise. I've got some good rainforest topsoil from a mature forest... Mostly just the top two centimeters of forest soil with the largest bits of twigs, leaves and roots removed. Some 3 gallon air pots. The rest will be direct-sown out in the field. They will still be subjected to a natural decomposition process in the soil, but hopefully things will happen quicker by removing most of the woody layer first.

[agroventuresperu]

I bought one kilo of seed. It turns out that is equivalent to only 35 seeds. I sacrificed two of them today for research purposes. I dissected them by hitting them with a hammer.

The woody endocarp measures mostly 4-6mm thick, yet tapers to as little as 2mm near the pointed end. It is up to 9-10mm thick at the opposite end.
The seed coat itself is also fairly thick, measuring 0.5 - 1mm. Also the seed seems to be an unusual shape with different chambers.

I'm thinking this is part of the reason why the species is endangered. It's hard for me to see how this could be commercially viable. Using a hammer, the seed was very difficult to extract without breaking into many small pieces. Even small fragments were difficult to extract from their chamber. Perhaps there is some specially designed tool specific to this species. Development of such a tool could help with conservation, since the species is mostly exploited locally for timber, and it doesn't sound like there are too many people planting trees, because they are one of the slower-growing timber species of the most commonly cultivated timber species of eastern Peru.

The seeds were delicious. Perhaps slightly better than the commercial walnut.

I started using the bench grinder on some seeds, but realized it was too tedious, so abandoned that idea. I only grinded 6 seeds (enough for two pots) so I will get to use these six as an experiment to see how they compare with the others, which I will not be sanding/grinding. For whatever reason it dulled the stone on my bench grinder, which is now smooth instead of a rough surface.

I've also decided to do the three day soak for all seeds as recommended by the Chanchamayo forestry publication I downloaded.

Of the six seeds I grinded, I took off maybe only a couple millimeters of endocarp on each seed. I'm not expecting much difference in germination times to be honest. I figure given ample organic matter, the endocarps and seed coats will undergo their process of decomposition at relatively the same rate.

Since the seed coats themselves are so thick, I suppose it's possible to separate the seeds from the endocarp and plant them without any endocarp, but I really don't have the knowledge to know how to separate the seed. Like I said, the shape of the seed looks a little weird and I don't see how I would extract it without breaking it in the process.

[Galatians522]

I bought one kilo of seed. It turns out that is equivalent to only 35 seeds. I sacrificed two of them today for research purposes. I dissected them by hitting them with a hammer.

The woody endocarp measures mostly 4-6mm thick, yet tapers to as little as 2mm near the pointed end. It is up to 9-10mm thick at the opposite end.
The seed coat itself is also fairly thick, measuring 0.5 - 1mm. Also the seed seems to be an unusual shape with different chambers.

I'm thinking this is part of the reason why the species is endangered. It's hard for me to see how this could be commercially viable. Using a hammer, the seed was very difficult to extract without breaking into many small pieces. Even small fragments were difficult to extract from their chamber. Perhaps there is some specially designed tool specific to this species. Development of such a tool could help with conservation, since the species is mostly exploited locally for timber, and it doesn't sound like there are too many people planting trees, because they are one of the slower-growing timber species of the most commonly cultivated timber species of eastern Peru.

The seeds were delicious. Perhaps slightly better than the commercial walnut.

I started using the bench grinder on some seeds, but realized it was too tedious, so abandoned that idea. I only grinded 6 seeds (enough for two pots) so I will get to use these six as an experiment to see how they compare with the others, which I will not be sanding/grinding. For whatever reason it dulled the stone on my bench grinder, which is now smooth instead of a rough surface.

I've also decided to do the three day soak for all seeds as recommended by the Chanchamayo forestry publication I downloaded.

Of the six seeds I grinded, I took off maybe only a couple millimeters of endocarp on each seed. I'm not expecting much difference in germination times to be honest. I figure given ample organic matter, the endocarps and seed coats will undergo their process of decomposition at relatively the same rate.

Since the seed coats themselves are so thick, I suppose it's possible to separate the seeds from the endocarp and plant them without any endocarp, but I really don't have the knowledge to know how to separate the seed. Like I said, the shape of the seed looks a little weird and I don't see how I would extract it without breaking it in the process.

Looks like a Black Walnut that got crossed with a mockernut hickory. Please let us know how it goes.

[MarktLee]

I have Ecuadorian Walnut which is probably the same as Peruvian and Colombian Walnuts. They were very easy to germinate.

[agroventuresperu]

I have Ecuadorian Walnut which is probably the same as Peruvian and Colombian Walnuts. They were very easy to germinate.

Would be helpful to know the scientific name. If it truly is a native species of Ecuador, then it's J. neotropica.

[agroventuresperu]

I planted all the seeds on September 22nd following 5 days of soaking with water changes multiple times per day as recommended in a seed pre-treatment study.

The six seeds that had been grinded were also soaked for the five days. Will see if those ones germinate sooner. I had soaked them inside a glass jar, and had to break the jar with a hammer to remove the seeds (apparently they had swollen a little bit over the course of the five days).

Worth noting that basically all the nuts were "floaters" which is supposedly a bad sign when it comes to other species of Juglans. Doubt that's the case here since the two nuts I cracked had healthy-looking (and tasting!) kernels inside. And the nuts also looked like they had a small air pocket inside. I've also read that the flesh on the outside of the nut contributes to this species being "floaters." It is near impossible to get all that flesh off, because it seems like it's fibrously stuck to the nut similar to how mangos are.

[Galatians522]

I wouldn't try this with seeds I was trying to sprout, but I have heard that black walnuts are sometimes husked by throwing them in the driveway and driving over them. May be something to keep in mind when you have loads of nuts... 20 years from now.

[agroventuresperu]

I wouldn't try this with seeds I was trying to sprout, but I have heard that black walnuts are sometimes husked by throwing them in the driveway and driving over them. May be something to keep in mind when you have loads of nuts... 20 years from now.

That would be nice. I need to get the soil fixed here before that. Plus this year's dry season has been extra hot and dry, which I'm hoping is not indicative of future trends. 900m might not be enough elevation for this species.