Post a reply

Avatar for RookiePresent
Sep 26, 2020 6:14 PM CST
Name: Alex
Rockford, Illinois (Zone 5b)
I'm familiar with the cold stratification process, but haven't been able to find any sources on what to do with the seeds before they get stored. For example, I have a paperbark maple that I collected seeds for, and the internet suggests a 120 day cold stratification period. 120 days from now would be late January - far too early for planting in the Chicagoland area.
For that 120 days that land, say, beginning of march for planting, I would have to start the process in November. But, what do I do with the seeds, or any seeds for that matter, for the next month? I know they have to be kept moist. Can I just start them whenever and leave them for an extra 30 days?

In nature, I know they just sit on the ground for months until winter comes around, but I'm not sure if I can do that and not kill the seeds. Apparently paperbarks have a 1-8% rate of filled seeds, so I want to take the best care of them.
Image
Sep 27, 2020 12:08 AM CST
Name: Daisy I
Reno, Nv (Zone 6b)
Not all who wander are lost
Garden Sages Plant Identifier
Welcome!

Put the seeds in a dry ziplock bag in the refrigerator to keep them fresh and safe until you are ready to stratify them.

When you are ready to stratify, transfer the seeds to a container. I use plastic lunch meat containers. Sandwich the seeds between layers of paper towels wetted with biofungacide. The fungacide will keep the seeds from molding in the damp environment of the container. If the seeds need to be re-moistened, use fungacide, not water. Don't let the seeds touch.

I always start seeds January 1 (or close). The seeds won't nesessarily take 120 days to germinate.
After a month, start checking the seeds once a week. As soon as you see signs of germination, plant them. If you don't catch them in time and the little roots start growing into the paper towel, cut a little circle of PP out and plant it with the root attached.

Good luck with your project. I would love to know how you do.
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and proclaiming...."WOW What a Ride!!" -Mark Frost

President: Orchid Society of Northern Nevada
Webmaster: osnnv.org
Image
Sep 27, 2020 9:19 AM CST
Name: Rick R.
Minneapolis, MN, USA zone 4
Garden Photography The WITWIT Badge Seed Starter Wild Plant Hunter Region: Minnesota Hybridizer
Garden Sages I was one of the first 300 contributors to the plant database! Plant Identifier Million Pollinator Garden Challenge
I agree.

There are always exceptions, but most seeds of all types prefer to germinate in either the 60-70F range or the 35-45F range. maples prefer the warm. Your 120 day stratification for Acer griseum is the recommended minimum. Since maples germinate in warm, you won't need to worry about germination with longer cold conditioning. But it would be a good idea to check them at 3-4 week intervals after the recommended treatment duration, just in case. With mother nature, there can always be he odd one out. It's a natural adaption for evolution.

Acer griseum in particular usually wants two cold seasons if you start with the cold treatment, according to the manual by Dirr I referred to in your other thread. Don't be surprised it you need a cold-warm-cold-warm treatment for germination. He implies that a warm-cold-warm might do the job, but doesn't say so. Good scientists never do, unless they know for sure that it is true.
When the debate is lost, slander becomes the tool of the losers. - Socrates
Avatar for RookiePresent
Sep 28, 2020 7:23 AM CST
Name: Alex
Rockford, Illinois (Zone 5b)
DaisyI said: Welcome!

Put the seeds in a dry ziplock bag in the refrigerator to keep them fresh and safe until you are ready to stratify them.

When you are ready to stratify, transfer the seeds to a container. I use plastic lunch meat containers. Sandwich the seeds between layers of paper towels wetted with biofungacide. The fungacide will keep the seeds from molding in the damp environment of the container. If the seeds need to be re-moistened, use fungacide, not water. Don't let the seeds touch.

I always start seeds January 1 (or close). The seeds won't nesessarily take 120 days to germinate.
After a month, start checking the seeds once a week. As soon as you see signs of germination, plant them. If you don't catch them in time and the little roots start growing into the paper towel, cut a little circle of PP out and plant it with the root attached.

Good luck with your project. I would love to know how you do.



Okay, that makes sense. So I can just keep store them in the fridge as is, but in order to stratify they need to be moist and cold, but dry and cold wont do anything but keep them safe and viable?
Avatar for RookiePresent
Sep 28, 2020 7:26 AM CST
Name: Alex
Rockford, Illinois (Zone 5b)
Leftwood said:I agree.

There are always exceptions, but most seeds of all types prefer to germinate in either the 60-70F range or the 35-45F range. maples prefer the warm. Your 120 day stratification for Acer griseum is the recommended minimum. Since maples germinate in warm, you won't need to worry about germination with longer cold conditioning. But it would be a good idea to check them at 3-4 week intervals after the recommended treatment duration, just in case. With mother nature, there can always be he odd one out. It's a natural adaption for evolution.

Acer griseum in particular usually wants two cold seasons if you start with the cold treatment, according to the manual by Dirr I referred to in your other thread. Don't be surprised it you need a cold-warm-cold-warm treatment for germination. He implies that a warm-cold-warm might do the job, but doesn't say so. Good scientists never do, unless they know for sure that it is true.


Indeed I saw this requirement for multiple cycles of cold-warm, and one thing that I saw to combat that was to do one cold cycle, and then extract the embryo from each seed and plant it directly to kick start it. That makes me nervous, because it seems easy to mess up and I don't have many seeds, but it should be fun.
Image
Sep 28, 2020 10:00 AM CST
Name: Daisy I
Reno, Nv (Zone 6b)
Not all who wander are lost
Garden Sages Plant Identifier
You mean cut the embryo out of the cotyledon? Do you realize how small a piece of seed that is?

Most people who grow seeds needing a warm, cold, warm cycle plant the seeds in pots while its warm, store them in a cold frame for the winter and put the pots back out in the spring. Mother Nature does the majority of the work. So instead of doing what I suggested (keeping the seeds cool and dry), start the stratification process now with the first warm cycle. Warm is always first. The seeds will germinate sometime next year.
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and proclaiming...."WOW What a Ride!!" -Mark Frost

President: Orchid Society of Northern Nevada
Webmaster: osnnv.org
Image
Sep 28, 2020 11:27 AM CST
Name: Rick R.
Minneapolis, MN, USA zone 4
Garden Photography The WITWIT Badge Seed Starter Wild Plant Hunter Region: Minnesota Hybridizer
Garden Sages I was one of the first 300 contributors to the plant database! Plant Identifier Million Pollinator Garden Challenge
but dry and cold wont do anything but keep them safe and viable?
-- correct

For most seeds, the warm cycle needs to be at least a month at 60-70F. For maples that produce their seed early in the year, it is more likely 2-3 months, but I don't really know. You have probably already found this out. In general, chemical reactions slow to 50% for every 10 degrees lower. So as colder temps approach, I don't think there isn't enough time for a warm treatment outside before winter for you. Keep them inside where it is warm. When it is time to switch to the cold treatment, put them in the fridge.

Depending on the species and the stage of growth, removing an embryo (embryo rescue (ER)) can be easy or hard. Sometimes they kind of just pop out, but there is always a special technique to it that will very from genus to genus. Embryos can be very teensy tiny and unmanageable without special tools, or unmanageable...period. On the other hand, and especially in cases where in the first warm conditioning the embryo is developing and growing, it might work with rudimentary care. But unless I already had practice with another maple species ER, I would still never try it when I have so few seeds, unless there was no other option.
The other major hurdle is the delicate and very vulnerable state of the embryo. It is so easy to damage tissue (again, depending on the species), and the embryo is incredibly vulnerable to pathogen attack.
When the debate is lost, slander becomes the tool of the losers. - Socrates
Avatar for RookiePresent
Sep 28, 2020 6:32 PM CST
Name: Alex
Rockford, Illinois (Zone 5b)
Leftwood said:but dry and cold wont do anything but keep them safe and viable?
-- correct

For most seeds, the warm cycle needs to be at least a month at 60-70F. For maples that produce their seed early in the year, it is more likely 2-3 months, but I don't really know. You have probably already found this out. In general, chemical reactions slow to 50% for every 10 degrees lower. So as colder temps approach, I don't think there isn't enough time for a warm treatment outside before winter for you. Keep them inside where it is warm. When it is time to switch to the cold treatment, put them in the fridge.

Depending on the species and the stage of growth, removing an embryo (embryo rescue (ER)) can be easy or hard. Sometimes they kind of just pop out, but there is always a special technique to it that will very from genus to genus. Embryos can be very teensy tiny and unmanageable without special tools, or unmanageable...period. On the other hand, and especially in cases where in the first warm conditioning the embryo is developing and growing, it might work with rudimentary care. But unless I already had practice with another maple species ER, I would still never try it when I have so few seeds, unless there was no other option.
The other major hurdle is the delicate and very vulnerable state of the embryo. It is so easy to damage tissue (again, depending on the species), and the embryo is incredibly vulnerable to pathogen attack.


You guys are both correct, I found a source from a seed seller, and am looking at their recommendations. They say to leave the seeds out somewhere warm for 17 weeks, which would take me into January, and then cold stratify them. They don't mention anything specially, so I assume I can just take them dry in a ziplock bag and let them sit for this first part of the cycle. I have already had them in the fridge for a day before this, hopefully that doesn't affect the seeds' chemistry.

It also says to leave them for another 17 weeks for the cold stratification process, which would take me into late May - which seems very late in the season to start seedlings, but I suppose they could germinate much sooner than that.


An observation that I had with my walnut seeds, was that I would seemingly lose some (they'd fail the float test) after passing the day before. As far as I know, the only difference between those seeds passing and failing was that they were left out and dried. This leads me to believe that drying out the maple seeds would also ruin them, so it's confusing/conflicting personal observations with what I'm learning from you guys. I'm sure you're correct, I just don't quite understand the nuances of seed storage. I could also have done the float test wrong and passed those seeds when they actually failed by not waiting long enough.

As far as the ER, you're right it sure sounds difficult. I will continue to research it, but with such a low rate of success, maybe doing the ER would result with a tree or two when I would otherwise lose all of the seeds. I think I will worry about that next year when the time comes and for right now I just want to make sure I'm setting myself up for as much success as I can.
Image
Sep 28, 2020 8:16 PM CST
Name: Rick R.
Minneapolis, MN, USA zone 4
Garden Photography The WITWIT Badge Seed Starter Wild Plant Hunter Region: Minnesota Hybridizer
Garden Sages I was one of the first 300 contributors to the plant database! Plant Identifier Million Pollinator Garden Challenge
No! The warm-cold-warm cycle MUST ALL be in moist conditions. Do 17 weeks warm and 14 weeks cold, then put them outside in the shade whatever the temperature is in April to finish. Even if it freezes. Having them "wake up" naturally with more gradual warming is better. That you had them in the fridge beforehand is just fine. Nothing happens inside the seed until moisture is add in the mix. This is why the first 17 weeks of warm cannot be dry. Nothing will happen inside the seed (except that it just gets old.) Again, the warm-cold-warm cycle MUST ALL be in in moist conditions.

Float tests only work for some types of seeds, despite what everyone wants to believe. Are these Black walnuts (with a deeply grooved surface) or English walnuts (with a smooth surface)? The float test has no relevance for maple seeds.
When the debate is lost, slander becomes the tool of the losers. - Socrates
Last edited by Leftwood Sep 28, 2020 8:26 PM Icon for preview
Image
Sep 28, 2020 9:07 PM CST
Name: Daisy I
Reno, Nv (Zone 6b)
Not all who wander are lost
Garden Sages Plant Identifier
Yes, what Rick said. That's why I said plant them now.
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and proclaiming...."WOW What a Ride!!" -Mark Frost

President: Orchid Society of Northern Nevada
Webmaster: osnnv.org
Avatar for Meandmyroses
Sep 29, 2020 9:30 AM CST

RookiePresent said:

You guys are both correct, I found a source from a seed seller, and am looking at their recommendations. They say to leave the seeds out somewhere warm for 17 weeks, which would take me into January, and then cold stratify them. They don't mention anything specially, so I assume I can just take them dry in a ziplock bag and let them sit for this first part of the cycle. I have already had them in the fridge for a day before this, hopefully that doesn't affect the seeds' chemistry.

It also says to leave them for another 17 weeks for the cold stratification process, which would take me into late May - which seems very late in the
season to start seedlings, but I suppose they could germinate much sooner
than that.


An observation that I had with my walnut seeds, was that I would seemingly lose some (they'd fail the float test) after passing the day before. As far as I know, the only difference between those seeds passing and failing was that they were left out and dried. This leads me to believe that drying out the maple seeds would also ruin them, so it's confusing/conflicting personal observations with what I'm learning from you guys. I'm sure you're correct, I just don't quite understand the nuances of seed storage. I could also have done the float test wrong and passed those seeds when they actually failed by not waiting long enough.

As far as the ER, you're right it sure sounds difficult. I will continue to research it, but with such a low rate of success, maybe doing the ER would result with a tree or two when I would otherwise lose all of the seeds. I think I will worry about that next year when the time comes and for right now I just want to make sure I'm setting myself up for as much success as I can.

If you have enough seeds, then try a few methods...
Personally, I think I would place them in a paper bag store them in a cool dry place then put them in a small plastic bag pop them in the fridge January
Leave them a few weeks, then sow them in a frost free area with decent light.
When I grew them for bonsai I would leave them on the tree for as long as possible, then pop in my incubator, 100% almost.
Stay safe
John
Avatar for RookiePresent
Sep 29, 2020 10:03 AM CST
Name: Alex
Rockford, Illinois (Zone 5b)
Leftwood said:No! The warm-cold-warm cycle MUST ALL be in moist conditions. Do 17 weeks warm and 14 weeks cold, then put them outside in the shade whatever the temperature is in April to finish. Even if it freezes. Having them "wake up" naturally with more gradual warming is better. That you had them in the fridge beforehand is just fine. Nothing happens inside the seed until moisture is add in the mix. This is why the first 17 weeks of warm cannot be dry. Nothing will happen inside the seed (except that it just gets old.) Again, the warm-cold-warm cycle MUST ALL be in in moist conditions.

Float tests only work for some types of seeds, despite what everyone wants to believe. Are these Black walnuts (with a deeply grooved surface) or English walnuts (with a smooth surface)? The float test has no relevance for maple seeds.


Yes they are all black walnuts. Okay, this makes sense. I will do the moist paper towel set up like I did with the walnuts and start their warm stratification cycle as you've described. I believe the source said that these seeds should be soaked in hot water for 24 hours, so I will do that first, create a moist environment in a zip lock and warm strat for 17 weeks, then cold strat for 14, then leave outside for natural warming and waiting for germination. How hard can it be?

I really appreciate all the help, but I would like to pick your brain on one more thing if you don't mind. I've seen several sources say that it's good to leave a gap in he seal on the bag when you're stratifying seeds for gas exchange. I've also seen stuff that says you should seal it, and just turn the bag over every few weeks so gases don't build on unevenly on one side of the bad. Is there truth to these? Does it matter?
Last edited by RookiePresent Sep 29, 2020 10:09 AM Icon for preview
Avatar for RookiePresent
Sep 29, 2020 10:06 AM CST
Name: Alex
Rockford, Illinois (Zone 5b)
Meandmyroses said:
If you have enough seeds, then try a few methods...
Personally, I think I would place them in a paper bag store them in a cool dry place then put them in a small plastic bag pop them in the fridge January
Leave them a few weeks, then sow them in a frost free area with decent light.
When I grew them for bonsai I would leave them on the tree for as long as possible, then pop in my incubator, 100% almost.
Stay safe
John


Close to 100% seems quite extraordinary for a species where parthenocarpy is quite common and seeds have a rate of less than 5% to be viable. That's impressive!
Last edited by RookiePresent Sep 29, 2020 10:11 AM Icon for preview
Image
Sep 29, 2020 10:24 AM CST
Name: Daisy I
Reno, Nv (Zone 6b)
Not all who wander are lost
Garden Sages Plant Identifier
Meandmyroses may be talking about seeds not needing a warm/cold stratification. Acer griseum has a germination rate of less than 10%.

I wouldn't seal the containers unless you open them weekly to check (a good idea anyway) as seeds need air, just like the rest of us. The biggest worry with stratification is mold and warm stratification is even worse. Soak the seed in a fungicide for as long as it takes to prepare the beds (a few minutes) then keep the medium damp with a fungicide.
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and proclaiming...."WOW What a Ride!!" -Mark Frost

President: Orchid Society of Northern Nevada
Webmaster: osnnv.org
Image
Sep 29, 2020 5:35 PM CST
Name: Rick R.
Minneapolis, MN, USA zone 4
Garden Photography The WITWIT Badge Seed Starter Wild Plant Hunter Region: Minnesota Hybridizer
Garden Sages I was one of the first 300 contributors to the plant database! Plant Identifier Million Pollinator Garden Challenge
I don't think Meandmyroses is talking about Paperbark maple.

Some air exchange is good, but I do seal my bags, and open them casually, perhaps every 3-4 weeks. More often is certainly not a problem. I seal them because otherwise if I forget for a while, they might dry out if they are open. In my opinion, you can do what you want. Remember you will be using freezer bags, not regular ones. The regular ones allow water vapor loss, and the moist paper towel can dry out even if it stays sealed.

RookiePresent, that's fine if you would like to do the hot water thing. This is not hot off the stove, this is hot but you can still put your hand in it. And of course, the water starts out that hot, but then continues to cool to room temperature.

If you use the paper towel method, don't be surprised if you get color stains on the towel and it looks icky. For molds and pathogens, you can attempt disinfection with bleach/fungicides. This would be must if you are doing ER. But for regular seeds, you have two methods, IMO. If you choose this one, you have committed yourself to its due diligence. Usually this is a safe way to go, but if an unlikely infection does occur, it will have the run of project, because there is nothing else there to stop or hinder it. You are almost obligated to do something about it, since you can't tell what the consequences might be.

On the other hand, without bleach or fungicide, it is very common that mold occurs. Sometimes a little, sometimes a lot. This is not anything to worry about. Molds feed on dead matter. You can change out the towel for a new one if you want. Remember to be gentle with the seed. Seeds are softer when they are moist, and you don't want to introduce a way for pathogens to enter the seed. If some seeds perish and some stay good, this also commonly happens. The perished seeds usually get taken over by molds. Almost invariably, those seeds were never viable to begin with. Good seeds can be completely covered with mold, and they will be just fine.

The good thing about this method IS the molds. They are rarely pathogenic, but being part of the web of nature, they compete with other organisms and organisms that are pathogens. Molds usually don't have fungicidal properties, but some do. (Remember penicillin?) Really, it's more of an artificial-natural balance that is encouraged when molds are allowed to grow, rather than any special chemicals produce.

Here are some Jeffersonia diphylla seeds that are of a special type of seed that must be kept moist to stay alive. I had temporarily kept them in a bag with a bit of moist paper towel for a few weeks before I could plant them. In the seed pod they naturally have a fatty aril attached to them that insects love (and molds feed on). It's impossible to remove this aril without damaging the seed, so it stays. See all the molds? And the seeds are happy campers. The bag is about 3.5 inches long. A little hard to see through the mold-clouded baggie, but you get the idea.

Thumb of 2020-09-29/Leftwood/93102e Thumb of 2020-09-29/Leftwood/ce5992

You can plant your seeds in soil after the warm period, or when you put them outside after the 14 weeks of cold. How hard can it be? The method is pretty easy, yes, but remember you are not dealing with easy seed.

Turning the bag over periodically is silly, and you are "confusing" the seed. Each time you turn the bag, you force the seed to re-orient itself according to the new gravity vector. How would you like it if periodically, you had to walk on the ceiling, with the furniture and everything else still on the floor above you? (At least until you re-oriented, and moved all the furniture onto the ceiling at your feet...)



What is happening with your black walnuts, I think, has to do with physics, not viability of the seed. That some seem to so quickly go "belly up" with the float test, is more likely the corrugated seed coat drying out more, becoming hydrophilic, and trapping tiny bubbles on the seed surface that is making them float.
When the debate is lost, slander becomes the tool of the losers. - Socrates
Last edited by Leftwood Sep 29, 2020 5:54 PM Icon for preview
Avatar for RookiePresent
Oct 2, 2020 8:05 AM CST
Name: Alex
Rockford, Illinois (Zone 5b)
Leftwood said:I don't think Meandmyroses is talking about Paperbark maple.

Some air exchange is good, but I do seal my bags, and open them casually, perhaps every 3-4 weeks. More often is certainly not a problem. I seal them because otherwise if I forget for a while, they might dry out if they are open. In my opinion, you can do what you want. Remember you will be using freezer bags, not regular ones. The regular ones allow water vapor loss, and the moist paper towel can dry out even if it stays sealed.

RookiePresent, that's fine if you would like to do the hot water thing. This is not hot off the stove, this is hot but you can still put your hand in it. And of course, the water starts out that hot, but then continues to cool to room temperature.

If you use the paper towel method, don't be surprised if you get color stains on the towel and it looks icky. For molds and pathogens, you can attempt disinfection with bleach/fungicides. This would be must if you are doing ER. But for regular seeds, you have two methods, IMO. If you choose this one, you have committed yourself to its due diligence. Usually this is a safe way to go, but if an unlikely infection does occur, it will have the run of project, because there is nothing else there to stop or hinder it. You are almost obligated to do something about it, since you can't tell what the consequences might be.

On the other hand, without bleach or fungicide, it is very common that mold occurs. Sometimes a little, sometimes a lot. This is not anything to worry about. Molds feed on dead matter. You can change out the towel for a new one if you want. Remember to be gentle with the seed. Seeds are softer when they are moist, and you don't want to introduce a way for pathogens to enter the seed. If some seeds perish and some stay good, this also commonly happens. The perished seeds usually get taken over by molds. Almost invariably, those seeds were never viable to begin with. Good seeds can be completely covered with mold, and they will be just fine.

The good thing about this method IS the molds. They are rarely pathogenic, but being part of the web of nature, they compete with other organisms and organisms that are pathogens. Molds usually don't have fungicidal properties, but some do. (Remember penicillin?) Really, it's more of an artificial-natural balance that is encouraged when molds are allowed to grow, rather than any special chemicals produce.

Here are some Jeffersonia diphylla seeds that are of a special type of seed that must be kept moist to stay alive. I had temporarily kept them in a bag with a bit of moist paper towel for a few weeks before I could plant them. In the seed pod they naturally have a fatty aril attached to them that insects love (and molds feed on). It's impossible to remove this aril without damaging the seed, so it stays. See all the molds? And the seeds are happy campers. The bag is about 3.5 inches long. A little hard to see through the mold-clouded baggie, but you get the idea.

Thumb of 2020-09-29/Leftwood/93102e Thumb of 2020-09-29/Leftwood/ce5992

You can plant your seeds in soil after the warm period, or when you put them outside after the 14 weeks of cold. How hard can it be? The method is pretty easy, yes, but remember you are not dealing with easy seed.

Turning the bag over periodically is silly, and you are "confusing" the seed. Each time you turn the bag, you force the seed to re-orient itself according to the new gravity vector. How would you like it if periodically, you had to walk on the ceiling, with the furniture and everything else still on the floor above you? (At least until you re-oriented, and moved all the furniture onto the ceiling at your feet...)



What is happening with your black walnuts, I think, has to do with physics, not viability of the seed. That some seem to so quickly go "belly up" with the float test, is more likely the corrugated seed coat drying out more, becoming hydrophilic, and trapping tiny bubbles on the seed surface that is making them float.


That's really interesting, I hadn't considered the seeds getting"confused" by turning them over. Does the turning really become an issue when they are starting/trying to germinate? Or at any step in the process?

I also didn't know that mold only fed on dead matter, but I have read other forums of people who have had walnuts seeds as well get covered in mold, and they just removed it and the seeds were fine. Even so, I did buy a fungicide that I will use with the paperbark seeds and the walnuts just for good measure. For the paperbark maple seeds, I opted to keep the wings of the samaras on for no particular reason, but since mold feeds on dead matter could the decaying wings of the seeds just be a medium for mold to grow?


In your pictures of the Jeffersonia diphylla seeds, you seem to have another piece of paper towel or something in with the seeds, what is it? I'm talking about the picture on the left.

I don't have to decide just yet, but I think I have to try ER simply because I'm not patient. I've been reading that if the seeds don't germinate next spring, they could need another year or 2 to germinate, and I simply don't want to wait. They say that doing the ER gives the embryo no choice but to germinate and most of them will germinate by handling them this way. But I haven't looked into the details of the process yet but I'd like to try.

I think it's really amazing how seemingly fragile yet hardy seeds can be. It's an interesting mix to learn about as someone who is just being exposed to everything.
Image
Oct 2, 2020 10:50 AM CST
Name: Rick R.
Minneapolis, MN, USA zone 4
Garden Photography The WITWIT Badge Seed Starter Wild Plant Hunter Region: Minnesota Hybridizer
Garden Sages I was one of the first 300 contributors to the plant database! Plant Identifier Million Pollinator Garden Challenge
It is all quite exciting, once you are exposed to so many of the nuances. I suppose this is true for most subjects, too.
-- -- -- -- -- -- -- - - - - - - - - - - - -- - - - - -
Perhaps "confused" is an inaccurate term here. When a seed is flipped over, it knows, and it knows what to do. Any of its processes that are gravity dependent need to expend more energy re-orienting. In a dormant seed, this is never a concern. After a seed breaks its seedcoat, the observed growth of roots and leaves or cotyledons are, of course, the obvious gravity dependent processes. For many seeds (not maples), these processes can happen during the cold period. But what happens before this? It is true that an embryo is fixed in place within the seed. But for those that continue their maturation process (needed before germination can occur) outside the mother plant, the relative position of different differentiation cells can be gravity dependent. In the end, does it matter? I am sure that all seeds have the ability to deal with a turning over event. But why needlessly (and repeatedly) force it upon them? We all do it some, unwittingly, but keep it to a minimum. Mark you bag, so you will know.

Regarding gas build up, I suppose it might be a concern in special cases, or depending on what organisms (beside the seed) might be operating inside the bag, but in general not a worry, especially if you open the bag every 3-4 weeks.

About molds, yes, the maple "wings" are dead and may or may not be decaying when the seed germinates. Molding is a decaying process and can happen independently or in conjunction with other decaying organisms. Usually, not a problem. With walnuts, though (and I am assuming the green hull has been removed), if the woody seed covering is molding, the conditions are far too moist, and cleaning them up or drying the bag out a bit is advantageous.

A more technical point, molds are just one kind of fungi. They are by far the most common that invade seed germination methods, and you can be pretty sure that any evidence you see with the naked eye is a mold. Although they themselves are rarely pathogenic to seeds, that doesn't mean that there can't be other pathogenic fungi, bacteria, etc., with them. But, just because there is mold, doesn't mean there is, either. As I said before, mold can be a good natural deterrent to help keep pathogens in balance, if there are any. Fungicides are the only sure way (outside of completely sterile conditions).

In my Jeffersonia pic, there is a piece of moist paper towel. It keeps the humidity in the bag at or near 100% to prevent the seeds from drying out. You may have also noticed there are at least two species of molds. If you try to do things the natural way, diversity is always a good thing.

ER involves sterile conditions. The embryo is naturally protected from the outer environs when it is in the seed. At a minimum you will need sterile tools, work surface, hands, seeds, medium (usually an agar) to grow the embryo, sealed growth chamber (like a test tube). Everything will be new to you, and I can almost guarantee failure. But you will learn a lot, and especially have a lot of fun trying. You might be able to find some maple seeds under some maples in your neighborhood to practice on first. They might look pretty beat up, but if they are firm, they are good to go. Even if you just investigate what the embryo looks like and how to remove it, that is hugely advantageous for future doings. It's important to work quickly with ER, because the longer it takes the more opportunity for contamination.
When the debate is lost, slander becomes the tool of the losers. - Socrates
Avatar for RookiePresent
Oct 5, 2020 8:55 AM CST
Name: Alex
Rockford, Illinois (Zone 5b)
Leftwood said:It is all quite exciting, once you are exposed to so many of the nuances. I suppose this is true for most subjects, too.
-- -- -- -- -- -- -- - - - - - - - - - - - -- - - - - -
Perhaps "confused" is an inaccurate term here. When a seed is flipped over, it knows, and it knows what to do. Any of its processes that are gravity dependent need to expend more energy re-orienting. In a dormant seed, this is never a concern. After a seed breaks its seedcoat, the observed growth of roots and leaves or cotyledons are, of course, the obvious gravity dependent processes. For many seeds (not maples), these processes can happen during the cold period. But what happens before this? It is true that an embryo is fixed in place within the seed. But for those that continue their maturation process (needed before germination can occur) outside the mother plant, the relative position of different differentiation cells can be gravity dependent. In the end, does it matter? I am sure that all seeds have the ability to deal with a turning over event. But why needlessly (and repeatedly) force it upon them? We all do it some, unwittingly, but keep it to a minimum. Mark you bag, so you will know.

Regarding gas build up, I suppose it might be a concern in special cases, or depending on what organisms (beside the seed) might be operating inside the bag, but in general not a worry, especially if you open the bag every 3-4 weeks.

About molds, yes, the maple "wings" are dead and may or may not be decaying when the seed germinates. Molding is a decaying process and can happen independently or in conjunction with other decaying organisms. Usually, not a problem. With walnuts, though (and I am assuming the green hull has been removed), if the woody seed covering is molding, the conditions are far too moist, and cleaning them up or drying the bag out a bit is advantageous.

A more technical point, molds are just one kind of fungi. They are by far the most common that invade seed germination methods, and you can be pretty sure that any evidence you see with the naked eye is a mold. Although they themselves are rarely pathogenic to seeds, that doesn't mean that there can't be other pathogenic fungi, bacteria, etc., with them. But, just because there is mold, doesn't mean there is, either. As I said before, mold can be a good natural deterrent to help keep pathogens in balance, if there are any. Fungicides are the only sure way (outside of completely sterile conditions).

In my Jeffersonia pic, there is a piece of moist paper towel. It keeps the humidity in the bag at or near 100% to prevent the seeds from drying out. You may have also noticed there are at least two species of molds. If you try to do things the natural way, diversity is always a good thing.

ER involves sterile conditions. The embryo is naturally protected from the outer environs when it is in the seed. At a minimum you will need sterile tools, work surface, hands, seeds, medium (usually an agar) to grow the embryo, sealed growth chamber (like a test tube). Everything will be new to you, and I can almost guarantee failure. But you will learn a lot, and especially have a lot of fun trying. You might be able to find some maple seeds under some maples in your neighborhood to practice on first. They might look pretty beat up, but if they are firm, they are good to go. Even if you just investigate what the embryo looks like and how to remove it, that is hugely advantageous for future doings. It's important to work quickly with ER, because the longer it takes the more opportunity for contamination.


You're a great teacher and I've appreciated you sharing your knowledge with me. I've spent several weeks now trying to figure it all out as a rookie and there's a lot of information. Seeing it written out plainly went a long way to clarify everything, and I again appreciate you (and everyone else who helped out) answering my questions!

I agree that ER will be especially difficult for me and getting in some practice is a great idea. There are plenty of maples around me that I could use to practice, and I think that is the best way to go about it.

Is it easier to do it that way, to just have the seeds in the bag in their own and then have a wet paper towel just in the vicinity? When I was reading tutorials, I got the impression the seeds needed to be wrapped, so for the maples I put the seeds in rows on one side, and then folded over the wet paper towel to create several "sheets" of seeds. For the walnuts, I wrapped them in bundles of 3 or 4 like a hobo bundle, also in wet paper towels. I had to take them out to spray them with the fungicide that just came in, and it would have been a lot easier if I didn't have to unwrap my set up every time I wanted to spray them or check on them.
Image
Oct 5, 2020 10:05 AM CST
Name: Rick R.
Minneapolis, MN, USA zone 4
Garden Photography The WITWIT Badge Seed Starter Wild Plant Hunter Region: Minnesota Hybridizer
Garden Sages I was one of the first 300 contributors to the plant database! Plant Identifier Million Pollinator Garden Challenge
Thank you for the complement. All of us were newbies like you at one time.

Lots of people use the moist paper towel method with great success. Having the paper towel not in contact with the seeds is fine if the seeds are already imbibed with moisture. But doing this is only required in very special cases. These seeds were fresh (already fully moist) and I chose to do it so I could physically watch the seed through the bag.

In general, if the seed is dry, it should be wrapped. Some seeds have seedcoats that won't absorb moisture well with just 100% humidity. They need liquid water. And you can't just look at a seed and guess which type it is.

Walnuts are different as they have a very very thick seedcoat. As long as the seed didn't dry out, all you need is to keep the environment highly humid. You can do that with a wet paper towel inside the freezer bag with as many walnuts as you desire. Make sure the towel doesn't dry out during the timeline. Myself, I would prefer to store them in just moist sphagnum peat (most preferred), vermiculite or potting mix . It keeps the humidity up, and holds a greater volume of moisture so it is less prone to drying out (therefore more foolproof). Sphagnum peat also has a natural anti-fungal quality that can be of assistance.

There are no set rules and there is a huge amount of leeway, but in general, if I use a baggie method-
--- for seeds up to an eighth inch I use a paper towel
--- for seeds over an eighth inch I use peat
When the debate is lost, slander becomes the tool of the losers. - Socrates
Avatar for RookiePresent
Oct 5, 2020 11:20 AM CST
Name: Alex
Rockford, Illinois (Zone 5b)
Leftwood said:Thank you for the complement. All of us were newbies like you at one time.

Lots of people use the moist paper towel method with great success. Having the paper towel not in contact with the seeds is fine if the seeds are already imbibed with moisture. But doing this is only required in very special cases. These seeds were fresh (already fully moist) and I chose to do it so I could physically watch the seed through the bag.

In general, if the seed is dry, it should be wrapped. Some seeds have seedcoats that won't absorb moisture well with just 100% humidity. They need liquid water. And you can't just look at a seed and guess which type it is.

Walnuts are different as they have a very very thick seedcoat. As long as the seed didn't dry out, all you need is to keep the environment highly humid. You can do that with a wet paper towel inside the freezer bag with as many walnuts as you desire. Make sure the towel doesn't dry out during the timeline. Myself, I would prefer to store them in just moist sphagnum peat (most preferred), vermiculite or potting mix . It keeps the humidity up, and holds a greater volume of moisture so it is less prone to drying out (therefore more foolproof). Sphagnum peat also has a natural anti-fungal quality that can be of assistance.

There are no set rules and there is a huge amount of leeway, but in general, if I use a baggie method-
--- for seeds up to an eighth inch I use a paper towel
--- for seeds over an eighth inch I use peat




I don't remember where I read it, maybe it was here, but I remember something about wanting to keep the seeds separate from each other in the bag? I really like the vermiculite/sphagnum peat methods, but I didn't have those materials handy and just went with what was easier. However, I hadn't heard that you could also just put them in potting soil, I have plenty of that and it never crossed my mind that it would achieve the same thing. Maybe it would be a good thing for me to change over to your method, of an indirect paper towel, so that in the spring I can see the seeds and get a better sense of any of them that are germinating without having to disassemble the bag?

I'm a little unclear on the walnuts' moisture capabilities. I'm running two "tests" I guess at the moment. I have one batch in the fridge, and another batch that I planted in the ground just to get experience doing both ways. The batch that I sowed I collected and didn't remove the husk for about 4 days. My logic was that they couldn't dry out, because they were covered in the husk and that would provide moisture and it was only 4 days - I was also just busy and wasn't ready to get to them quite yet. I read a study about seed moisture content, and the time periods that it said it took a seed to lose quite a bit of moisture was quite a long time - weeks, I believe. So I thought 4 days wouldn't be an issue and if they can survive on the forest floor for a season and not lose enough moisture to be bad, then 4 days on my table would be nothing at all.

I also have no sense of whether or not the seeds are imbibed with moisture or not. The seed coat on the acer griseum is also quite hard, and I think I can only assume they are imbibed because I soaked them in water for 24 hours. I did no such thing with the walnuts.
Since the seedcoat is so thick for walnuts, I imagine the outside could be dry, but the inside could be an acceptable level of moist and you wouldn't have any way to tell.

In hindsight, I completely forgot to float test that second batch of walnuts. That would have been a good idea after they sat for 4 days, hopefully they turn out okay. Would it be worth it to dig them up and test them?

Only the members of the Members group may reply to this thread.
Member Login:

( No account? Join now! )

Today's site banner is by sedumzz and is called "More Tassel Fern"

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.