misteroman wrote:I have a 10,000 sq ft basement underneth the motel with no windows at all and most don't even know its there. What should be hide Chad?
I'm thinking 50-100 tons of small copper colored discs
68Camaro wrote:Any suggestions on affordable source of supply for metallized mylar bags?
68Camaro wrote:I re-read the blog that I saw that in - and it implies that seeds need access to oxygen. After seeing your note, other searching indicates that the critical parameters are dryness and temperature. There seems to be some consensus that sealing in metalized mylar bags with desiccant, stored in the frig or freezer, is the recommended practice. Suggestion is that they shouldn't see the freezer until they've been dried to a specific level - this prevents the cells from bursting when the water changes to ice. What is less clear is the effect of vaccum.
As to best practice, in summary, in the FAQ at the following, http://www.ars-grin.gov/ncgrp/center_faq.htm#Q15 I found
What is the best way to store seeds? Dry seeds to about 20 % RH and store in vapor-proof containers in a cold place like a home freezer.
Other links
http://www.seedforsecurity.com/article.php?articleid=27
http://www.ars.usda.gov/is/AR/archive/s ... ed0998.htm
http://www.survivalseedbank.com/
http://readynutrition.com/resources/sec ... _30122009/
I had a hard time finding a good resource that seemed to know what it was talking about with regard the oxygen issue. I finally found this one.
http://www.nsl.fs.fed.us/Chapter%204.pdf
Excerpting from it, it turns out that it *depends* on the seed type.
Atmosphere. Reduction of oxygen levels will slow
metabolism and increase longevity of seeds, but it is not
practical to regulate this factor precisely in operational storage
situations. In past years, seeds of Populus L. species
were often stored in vacuum desiccators to extend storage
life; the beneficial effect in this case was reduction of oxygen
for metabolism. (Proper drying and refrigeration have
replaced vacuum storage for Populus now.) Recalcitrant
seeds, with their active metabolisms, require oxygen to such
a degree that it is quickly depleted in airtight storage containers,
and the seeds die. Any recalcitrant seeds must be
stored in containers that afford free access to the surrounding
atmosphere.
You'll need the following to read on...
http://en.wikipedia.org/wiki/Orthodox_seed
http://en.wikipedia.org/wiki/Recalcitrant_seed
http://www.ars-grin.gov/ncgrp/center_faq.htm#Q20
From the above:
What is a recalcitrant seed? A recalcitrant seed, in contrast to most crop seeds, is a seed that cannot survive drying and so cannot survive in the freezer. Preservation of recalcitrant seeds requires a procedure that prevents damage by drying or freezing. This has been accomplished in several species by excising the growing part of the seed, optimizing the water content, and cooling very rapidly. Recalcitrant seeds are frequently produced by temperate-zone forest trees, riparian species, and plants from the tropics. Examples of recalcitrant seeds are oak seeds, wild rice, and citrus.
In summary, it says....
Storage Recommendations
Orthodox Seeds
All orthodox seeds should be stored in moisture-proof,
sealed containers with seed moisture contents of 5 to 10%.
If the period of storage will be 3 years or less for true orthodox
species, or 2 years or less for sub-orthodox species,
temperatures of 0 to 5 °C are sufficient. For longer periods
of storage for both types of orthodox species, freezers (–18
to –20 °C) should be used.
Temperate-Recalcitrant Seeds
Temperate recalcitrant seeds should be stored with moisture
contents at least as high as that present when the mature
seeds were shed from the tree. (Refer to genus chapters in
this manual for information on individual species.) This
moisture level must be maintained throughout storage,
which may require occasional rewetting of the seeds.
Temperatures should range from 0 to 5 °C, although 1 or 2
degrees below freezing will not harm most species.
Containers should be basically impermeable to moisture
loss, but must allow some gas exchange with the atmosphere.
Polyethylene bags with a wall thickness of 0.075 to
1.0 mm (3 to 7 mils) are suitable. Some oak acorns can be
stored for 3 years in this fashion (table 3), but some viability
will be lost. For other recalcitrant species, few data are
available.
Tropical-Recalcitrant Seeds
Storage of tropical recalcitrant seeds is done in the same
manner as storage of temperate species, except that temperatures
must be kept at a high level. There are differences
among species but the lower limits are generally 12 to 20
°C. Successful storage for more than 1 year should not be
expected.
Treetop wrote:You said desiccant was advised.
Treetop wrote:Im not seeing anyone suggesting to use desiccants from your government links. Where is it exactly?
I had a hard time finding a good resource that seemed to know what it was talking about with regard the oxygen issue. I finally found this one.
http://www.nsl.fs.fed.us/Chapter%204.pdf
Excerpting from it, it turns out that it *depends* on the seed type.
Atmosphere. Reduction of oxygen levels will slow
metabolism and increase longevity of seeds, but it is not
practical to regulate this factor precisely in operational storage
situations. In past years, seeds of Populus L. species
were often stored in vacuum desiccators to extend storage
life; the beneficial effect in this case was reduction of oxygen
for metabolism. (Proper drying and refrigeration have
replaced vacuum storage for Populus now.)
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