Ghazanfar and Raul, Thank you for your replies. What you advocate, is exactly what I do, yet I am in the process of losing my second shipment of Ludwigia sp. pantanal. I am floating them in a variety of conditions, including very bright light, plenty of nutrients, other plants thriving floating that ought to be rooted, and all my pantanal stems are rotting, rapidly. It seems that this stem rot, once it is started, is unstoppable. I had the same experience with Eusteralis stellata. The only way I was able to get that species established was to get some that was grown emerse.
Your advice on preparing plants for shipping is also exactly what I do, and still I have occasionally received reports that plants I have shipped via Priority Mail have died. Fortunately, at least 80% of the time I have received reports that they arrived in good shape.
If submerse-shipped E. stellata and its look-alikes lose their leaves, in my experience, there is no chance of recovery. The speed at which they go downhill indicates to me that their disintegration is not due to something like their starving from lack of light or nutrients. It is more like a rapidly-spreading infection to which submerse stems are susceptible and emerse stems are not.
I would like to propose an experiment for somebody who has some submersed E. stellata or look-alike to spare:
A. Cut some stems as you would do if you are going to ship them.
B. Wrap some in wet paper towel or newspaper and put in a plastic bag
exactly as though you were going to ship them. Place them in the
dark and check them daily for signs of deterioration.
C. Let the remaining stems float in the tank for a week. Do they
deteriorate? Do they recover and start to grow some roots?
D. If they do recover and start to grow some roots, wrap for shipping
and place in the dark as you did the previous stems. Monitor daily
for deterioration and see if they last any longer than the freshly cut
stems did.
My hypothesis is that the recovered stems will last longer in the dark because they have healed the cut ends or have set up a barrier to infection at the next node from the cut end.
If the experiment comes out as I expect, it would indicate that stem plants should be allowed to recover for a while in their tank before being shipped. If the experiment does not work out as expected, i.e. the cut stems all rot floating in the tank in which they were cut, (not too likely) or the recovered stems die as fast in the dark as the freshly cut ones, then sending emerse stems is the only way to improve shipping survival.
I hope someone who has submersed E. stellata or look-alike (I don't) will do this experiment and report back to all of us. I an convinced that some simple research can find ways to improve survival during and after shipping.
