I may have misunderstood your proposed design, but surely you just need to
blow air horizontally across a thin stream of falling seeds? No laminar flow
issues, and not really any need for calculating - all seeds will fall
through the same breeze. Adjust the wind speed or any baffles until light
ones get blown to the side and heavy ones fall into your collector. If the
proportion of small ones that get through is too highl, put the collection
back in the top and do it again.
This is basically how winnowing works, isn't it?
We were at cross purposes. Your idea is one that could work, but I
have gone for a vertical design, where air is sucked upwards by a fan
at the top, seed is put in half way up the duct, and only the heaviest
falls down, the rest is blown out of the top through the fan.
OK, this is basically the Millikan oil drop experiment to determine the
charge of an electron, which I have done. In that case the electron has a
predictable charge, the weight and air resistance of the oil drops are
essentially constant and the force is provided by electrostatic plates -
easy to get parallel (equivalent to laminar flow of your wind) and easy to
adjust minutely. I think you will struggle with your design and I doubt very
much if you can calculate the speeds required in advance, given all the
variables that apply to wind resistance of real objects, but good luck.
Being unable to join in the genetics debate I'd like to ask a simple
In my experience Alder grow fast and die early. They also have little
structural value, rot quickly and burn so fast as to be useless in an open
fire or log-burner.
About all I can see left is as Biomass fuel and my reading suggests that
Willow and Hazel are better in most respects.
puzzled and hoping for enlightenment....
It is true that some see alder as a competitor to willow, I hadn't
heard of hazel, but it is also a fast-growing "weed tree". Alder burns
well, so that is a GOOD, not a bad point, and kept under water, it
doesn't rot and I think much of Amsterdam is built on pilings made of
But I am interested in taking alder in a DIFFERENT direction. All
organisms can be changed by selection, evolution is natural selection,
and that is what makes alder (and all wild plants and animals) what
they are today. Domesticated plants and animals have been changed by
breeders and that is what I am trying to do. The odds are against my
project, but I may find a Koh-i-Noor seed which changes everything.
I do understand you here, Michael. I was watching the RI Christmas
lecture a few weeks ago, and was struck by the extent to which the early
progenitors of today's cereal crops had been changed out of all
recognition by selective breeding. Many, many generations of selective
breeding, to be sure, but maybe with greater knowledge you can
accelerate that. I certainly wish you well with it, anyway.
Particularly struck by your comments on the wet rot resistance of alder.
Now if you can breed it to produce good-sized strong timber of similar
durability, that would be something.
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