Seed cleaning for the SX

[gastil]

After a several-year hiatus, I finally got around to cleaning some seed and packaging some bulbs for the exchanges. Not a lot of material, but I feel like it puts me back in the game.   I know the deadline for seeds to arrive to Jan is not until the 15th but I leave tomorrow. 

Seeds sent today:
Merwilla plumbea (very few) wiki link
Freesia laxa subsp. azurea (too many) wiki link
Tropaeolum hookerianum subsp. austropurpureum wiki link
Ixia rapunculoides wiki link
Orthrosanthus multiflorus 'Morning Flag' wiki link
Habranthus robustus (tentative ID) wiki link

After I already taped up the envelope I found another packet I had meant to send so I tucked it just inside the fold. Jan: be on the lookout  as it may fall out when you open the envelope. 
Lachenalia orchioides ssp. glaucina wiki link

It took awhile to clear a space to work and find my seed-cleaning screens I made back in 2020 but have not used since then. They worked! I also used the tilted, folded paper method David taught me. Each seed has its own character, its own way of cleaning. Some are trivial and some are laborious. But after awhile I got into the rhythm of the process. I wish I'd started sooner. Here are some process pics.

[gastil]

... and here are the bulbs on their USPS journey to Bridget. I know she does not need them til the 21st. Bridget: open the Boophone plastic container asap and let them breathe. I should have punched holes. 

Boophone notes:
Grown from seed from Ken Blackford sown fall 2020. These are the summer-dormant leaf ones but their roots are not dormant. DO NOT cut off the roots. There are only seven deemed viable enough to make the trek to the BX and their new homes. And one of those is borderline. 
wiki link: https://www.pacificbulbsociety.org/pbswiki/index.php/Boophone#haemanthoides

Dichelostemma notes: 
The name is now Dipterostemon capitatus
wiki link: https://www.pacificbulbsociety.org/pbswiki/index.php/Dipterostemon
Variety of sizes from first-year seedling to blooming size but none of the maximum size bulbs are in this donation. Those grow deeper than I dug. The two kinds grow adjacent so have likely mixed a lot of pollen but I still separate by where I dig them. Sorry I wrote the old name, miss-spelled, on the bags. I'm reminded by my own wiki photo that I did get some from Jim Duggan even earlier than those from Telos. 

Freesia laxa subsp. azurea aka 'cruenta' notes:
We call them "blue" but they are a pale lavendar with darker purple splotches. I am careful not to allow any cross-pollenation with the orange or white. These do come true to color and are easy to grow from their abundant seed if you sow it fresh. 
wiki link: https://www.pacificbulbsociety.org/pbswiki/index.php/freesia#laxa

Moraea polyanthos notes:
The corms are super lightweight, not dense like other genera. Do not be thinking these are empty just because they are not dense. Variety of sizes from maximum to 1-yr-olds. Open pollinated with lots of other Moraea but I have not seen evidence of mixing. There is abundant evidence of self-sowing so if you live in my climate, you will have a little lawn of seedlings all around the parents.  
wiki link: https://www.pacificbulbsociety.org/pbswiki/index.php/MoraeaSpeciesSeven#polyanthos

Scilla vincentii notes:
I received these from two sources, a BX years ago and more recently iLahee. Variety of sizes including blooming-size but not the maximum size. Again, those grow deeper than I dug. Another name change. At least one of the two sets I got did come with the "mauritanica" word and my notes do have "spelling?" so I believe these are actually Hyacinthoides mauritanica ssp. vincentina
or, received as such. But mine are definitely NOT dwarf. 
wiki link: https://www.pacificbulbsociety.org/pbswiki/index.php/Hyacinthoides#mauritanica
So I guess we have to call these Hyacinthoides something. I may seek Mystery Bulb advice on the forum before the BX starts so you can more properly list these. I have abundant photos, as these are beautiful in bloom. 
They are definitely NOT ordinary "bluebells". I have those too.

[David Pilling]

All those laborious wiki links can be automated by marking the species name and then clicking on the 'mark latin species name to wiki link' button above, it is the right hand in the first group of three buttons from the left in the reply button bar.

An amazingly wonderful feature that Martin added.

Yeah shaking seed to separate it - I should have made a video, I should have made a machine.

[Uli]

Hello David!
Please make this video about cleaning seed. I have to do a lot of cleaning and would very much appreciate any improvement on my technique which is far from perfect.

[gastil]

There is a wiki page on how to clean seeds where David demonstrates: CleaningSeeds

And viola', the species link gadget works great. 

[David Pilling]

Please make this video about cleaning seed.

Alas I have no seeds to clean. The wiki page that Gastil has cleverly got a link to above explains a bit. I had forgotten how I used to process seeds - benefits of writing things down on the wiki.

"David Pilling wrote that shaking sets up a particle size gradient" - good grief.

I never thought why this works. For a particular size of shake, small enough items become detached from the surface whilst bigger ones cling on. The skill is adjusting the amplitude to match what you're trying to separate.

'small' might mean size or weight, or a combination (density).

Nice additions to that page this hour by Gastil. The "Nested sieves of various aperture" look very desirable.

[gastil]

A whole lot of shaking has been going on here. 

While repotting, I discovered if I gently-but-firmly bump the side of a pot a few times the larger and lighter pumice "floats" to the top while the dense coarse sand settles. While a uniform mix is best for drainage, having the pumice on top eases watering. And I have an unverified hunch the shade fraction and higher albedo cool the soil. 

Shaking screens sideways sorts differently than vertical shaking or random agitation. And the sequence matters. If possible, remove the dust first, not last, or you get that fine dust all over the sieves. If you put the collected pods or stems of pods into a paper bag for drying, try to reach out the pods, not just dump out the whole bag along with dust. 

The shaking David recalls from his tilted folded paper method of seed cleaning is a much more subtle tapping. The type of paper also has significant effect: slick printer paper versus rough-surface paper towels. Paper towels are good for trapping fine dust. The used towels can then be used to dust off the chaff blown all over the room by winnowing attempts. 

Seed cleaning requires curious experimentation and patience, much like growing bulbs from seed. 

The shaking for seed cleaning I would describe as an arcane skill or craft. I'm curious how others clean their seeds. The skill which eludes me most is finding the time and patience for the task.

[David Pilling]

Shaking screens sideways sorts differently than vertical shaking or random agitation.

For a virtuoso of the screen maybe.

Gravity is on your side for all this shakin, chance to get a grant to investigate cleaning seeds in a zero-g environment.