Maple Seeds after Hot Summer

[bjk]

The big plan for this year was to collect and propagate various Japanese Maple species from seed and begin my grafting career. The recent extreme hot spell saw mine in the general garden, as well as trees elsewhere, shedding seed or rapidly drying seed on the tree a lot earlier than I'd expect.
Does anyone have any experience or thoughts that seed viability will still be constant - just earlier ?? - or is it likely to be reduced.

[Watto]

That's a great question, and I hope someone knows the answer. It might be up to you to do some experimenting and let us know the results?

[bjk]

OK I have started this off already before better advice emerges by following a sort of instinct which may or may not have some merit.

Plan A
I have divided the seeds I've picked up off the ground (!) and a few off the tree which are clearly dry winged -(35-50) into two lots.
Heap No1. I put these in a ziplock bag with a bit of just damp vermiculite in a paper towel.
Heap No2 I soaked for 24 hours. About 85% sank which indicates viable seed if Conventional Wisdom Rule #1 holds true. Those that sank I have put in another ziplock bag with just damp vermiculite in a paper towel.
I've placed both bags under a piece of carpet on the concrete floor of the shed for probably the most consistent temperature I'm likely to find this summer.
Time will pass. About early May, I'll retrieve them, take 'em inside the house for a week or two, and then pop 'em in the Shed fridge to stratify till end of August. I'll have a squint at the soaked bag to check for germination and both bags for mould.

Plan B I took 6-8 samaras and split them. With a fine blade, I opened them and extracted the inner seed which was brown (I dunno if this is Ok or not) I did this just to see what it looked like. I have now planted them in a container of vermiculite and left them in the auto watered shadehouse.
Again, Time will pass.

Have I achieved anything ? I don't know.
Again Time will pass !!

[shibui]

Hi BJK,
Good to see an enquiring mind attempting to answer questions. keep it up.

Viable seeds should be white inside. I'd guess the ones you are picking up off the ground at this time of year have aborted due to heat and the tree has shed them as unviable (or tree has shed some of the seed to conserve energy and save other seed and/or its life. Seed shed before maturity is likely to be unviable so result is the same)
That said, unexpected things have happened before and no doubt will in future. Your trials may yield valuable knowledge so keep trying.

Maple seed usually mature at about the same time as the leaves drop. hoping the trees are able to retain some to maturity for you.

[bjk]

I almost wish i hadn't opened my mouth and my mind !!!
I've taken a few steps - -

First -The seeds I'd squirrelled away in plastic bags with a bit of moist Paper were too moist and some fungi had started. I abandoned that and got hold of some very fine mesh bags at Spotlight. I put what seeds looked ok in these bags and laid them in the shed coolspot (The floor under a bit of carpet)
Second - I began researching. I downloaded Norman Deno's book "Seed Germination Theory and Practice" (Google it - its in PDF Format - I lost the link) in which he outlines the seed germination practices for some 2500 plants, grasses, trees etc. It was written in 1993 and has a couple of supplements. Very easy to read and interesting. I'd recommend it because it shoots down a lot of urban myths and just tells you what you need to do for just about any plant. For example different maple species have completely different and opposing techniques. Its all about inhibitors, time, seed dispersal protection, the Dry and Wet Storage and Temperatures of 40 and 70 Deg (Farenheit)
Third I've placed some straight in the frig - dry - and they are under observation.
Fourth I've placed more seeds in these bags in the shed coolspot awaiting late May/Early June for Stratification and I'll add to these as the season progresses.

I think my original question as to whether these early seeds are viable is now irrelevant in light of Deno's book and the ones I opened and looked at . I think they are quite OK.
I haven't yet got my head around what my final process will be.

[bjk]

Well, Time has moved on. As mentioned, I stratified the seeds I'd picked off the ground. I stratified the seeds I picked off my garden trees as well as some of my near my neighbours and stole some from various unnamed sites.
About September I took them from the fridge and planted them in trays about every 2-3 weeks - all identified, all then kept under moist conditions . I chucked several handfulls into various spots around the garden In all, I probably put 3000 seeds into trays or soil.
I ran out of bated breath ! At this time (November) TWO seeds have germinated and i must say only in the past 2 weeks!!!! To say I'm P---d is an understatement.
To top it all it looks like about 7 or 8 acer ukurundense have germinated of their own accord in the gravel driveway and near garden. At least I might have somethingto show but nothing due to my efforts.

At varying stages after taking from the fridge, I opened seed to see what was inside. In ALL cases I had moist, embryos for want of a better description - or whatever the right name might be. They looked like they were ready to scramble out of the compressed sumosa and sprout.

What have I achieved - basically nothing
What have I learnt -basically nothing
What will i do next year - Dunno

I would however like someone to really detail a sure process unless someone can offer an explanation that is reasonably scientific and acceptable about my process or the season..

BJK Bugga !!

[shibui]

I have 2 methods for germinating acer seed:
1. Do nothing. Let the seeds fall on the ground. In spring thousands of seedlings will emerge - help yourself to as many as you need.
2. Assuming you have no garden beds for the above method, Collect seed. Sow immediately into seed trays or pots. Leave them outside all winter, water if necessary. In spring seedlings will emerge.

Sometimes I think we make it overly difficult for ourselves (stratification, etc)

[Jason]

I have 2 methods for germinating acer seed:
1. Do nothing. Let the seeds fall on the ground. In spring thousands of seedlings will emerge - help yourself to as many as you need.
2. Assuming you have no garden beds for the above method, Collect seed. Sow immediately into seed trays or pots. Leave them outside all winter, water if necessary. In spring seedlings will emerge.

Sometimes I think we make it overly difficult for ourselves (stratification, etc)

I've actually heard you say this before shibui, and it made me curious.

I don't know too much about the whole process... so forgive my ignorance Could it be because these tree's are growing in Aussie temps, so that never actually experience any of these 'freezing' periods, so therefor the seeds they produce, don't actually need those freezing temps to germinate?

I've really got not idea myself, but something you said in another thread sparked the thought, so thought I might ask I've tried my hand at stratifying maple seeds before, and very quickly gave up as they all went mouldy, and the missus didn't appreciate mouldy seeds in the fridge

[kcpoole]

When we stratify seeds, we do so in the fridge not the freezer so they do not need the Freezing just need to be cold (below +6 or so) for an extended time.
I Sydney, most daytime temps over winter are 15 Deg or so and rarely get below 5 over night now.

Shibui lives in the Vic highlands so get a few months of much colder temps than I do.

Pick up or collect the seeds, straight In the fridge for a month or 2 then into seed trays in filtered sunlight. Watered every day by my sprinklers. I Have propagate maples, liquidambar, Chinese elm using this method reliably.

Ken

[kcpoole]

I do not know whether the seeds wil be damaged by leaving them out thru summer, but doubt it. The ground will tend to keep them cooler and presumably lyning under other trees should not get too hot.
Many people have collected seed and sowed then after a season or 2, or sowed them 1 year and left them till the next before they sprouted.

Ken

[Ray M]

Hi bjk,
The following link is a post I did on Trident Maples. viewtopic.php?f=9&t=6157&hilit=maple I certainly don't claim to know all about this subject. I didn't stratify any of my seeds. The post will explain how I planted them. Also in the thread you will see the date that the seeds were planted. I am not sure if this process is the same for Japanese Maples. There are others on Ausbonsai that would have had more experience with Japanese Maples. Hopefully they might clarify if the method used for Trident's would work the same with Japanese Maples.

Please keep us updated.

Regards Ray

[rodm]

Hi all, reading with much interest about seed propagation. sad you put alot of effort for so little. I'm going to collect seed of local Japanese maples and sow them straight after collecting and sorting. My theory is if I did pick them up ans sow them they"d still be on the ground and would probably self sow. I'm just helping out a little. Will keep all posted as to the progress. cheers Rod

[shibui]

Could it be because these tree's are growing in Aussie temps, so that never actually experience any of these 'freezing' periods, so therefor the seeds they produce, don't actually need those freezing temps to germinate?

I don't think a couple of years in milder temps is enough to change the genetic programming of a species Jason. I think it more likely that the Acers we are growing just don't actually have the germination inhibitors that require stratification to break so they will grow just as well without stratification and would do so anywhere in the world.
However, as KC says I am in a relatively cool part of Aus and maybe the natural winter temps is enough to break any dormancy. Interesting that Ray lives in Sydney and germinates tridents without stratification too. Looks more and more like tridents, at least, do not need stratification - as I said, sometimes we make something that should be easy quite difficult (maybe because we can then skite about having achieved something unusual or difficult?). Maybe we can get someone in a warmer climate to do some trials with A. palmatum to check germination without cold treatment. I can supply seed that I know is viable (next autumn)

I do not know whether the seeds wil be damaged by leaving them out thru summer, but doubt it. The ground will tend to keep them cooler and presumably lyning under other trees should not get too hot.
Many people have collected seed and sowed then after a season or 2, or sowed them 1 year and left them till the next before they sprouted.

Ken, I have read that maple seed goes into deep dormancy when stored or dried. Not dead but very difficult to germinate. Fresh seed definitely germinates better.

[Jason]

Could it be because these tree's are growing in Aussie temps, so that never actually experience any of these 'freezing' periods, so therefor the seeds they produce, don't actually need those freezing temps to germinate?

I don't think a couple of years in milder temps is enough to change the genetic programming of a species Jason. I think it more likely that the Acers we are growing just don't actually have the germination inhibitors that require stratification to break so they will grow just as well without stratification and would do so anywhere in the world.

Thanks for that Shibui, appreciate the reply Understand what you're saying now

[bjk]

Well, More time has passed and I've received a fair bit of advice as well as a few diversions on the way both from here and around the traps.

This year the local trees haven't delivered an abundance of seed to pick. (I'm in the Mt Lofty ranges in South Aus) One favourite tree has actually died ! I've collected what I can and divided them into 3 lots
Lot 1 in sharp sand trays in the open where the rain, frost and weaather will get 'em.
Lot 2 will stay in the shed in airing bags until time to drop them in the fridge - About end of June (I'll probably do the soaking trick for 24 hours to this lot before they go inthe fridge)
Lot 3 will stay in the shed in more airing bags to be placed in growing trays in August.

I'm not a believer in the evolutionary move of Australian seed not needing stratification - be it by refridge or natural means. Thats too big a stretch in our short history and Norman Deno's research, methinks. Some past failures might just be caused by the simple failure of the bees - or whoever - to do their thing.

So, Time will pass again

BJK