Smoke Pre-treatment of seed

Geoffrey Barnier CoffeeCamp@optusnet.com.au
Wed, 24 Aug 2005 14:18:19 PDT
Hi,

I've recently joined this forum because of my interest in warm climate geophytes, esp. Australian natives & crinum. I live in The Northern Rivers of the north coast of sub-tropical New South Wales, Australia, in the hinterlands of Byron Bay where I have a warm climate bulb nursery on my 5 acre property which is also a registered Wildlife Sanctuary & B&B/eco-retreat.

I learnt early & at my cost when I first settled here 4 years ago from London, UK to forget about daffs & tulips & other traditional & cool climate bulbs.  I then found a passion in the little known & rarely available warm climate bulbs, especially the Amaryllids & the Australian native Amaryllids in particular: proiphys, crinum & calostemma.

Some seed of native Australian geophytes I cultivate requires pre-smoke treatment, esp. the Thysanotus species (Fringe Lily).

One of our universities published an informative article on smoke pre-treatment of seed. The page is not currently available directly from the university's server for some reason but may be viewed from Google's cache at: 

http://64.233.187.104/search/…

where you will find, sadly, that it was the South Africans & not the Australians (as Gary in Hilo kindly attributed it to) who discovered that smoke or smoke-derived products had an amazing effect on seed germination & dormancy. Prior to de Lange's & Boucher's discovery, it was not known which aspect of the fire was responsible, whether it be heat, ash, the consequent lack of competition etc.

I wouldn't use culinary smoke flavours that Diane Whitehead asks about although I did come across that suggestion on an American nursery website. I believe that the chemicals used for flavouring would be quite different from those found in a forest fire.

In Australia, we have available a coloured slip of 'smoke-paper' which is impregnated with the chemicals found it bush fire smoke. This paper is put in 50ml of water & the seeds are soaked for 24 hours in this solution before sowing normally. This recreates the conditions similar to the start of the rainy season after a fire & triggers germination.

Greening Australia also suggests spraying a fine mist of water through smoke or buying a commercial preparation. However, they do warn that Smoke Water is still in the developmental stage. See: http://www.greeningaustralia.org.au/NR/rdonlyres/ 0D16FD21-60EF-470D-8227-1FB8D364C172/1380/5SeedTreatments.pdf 

I even saw a British site suggesting you sow the seed as normal, then light a little fire of twigs & leaves on top of it. Original but I wouldn't recommend it.

A water pipe or hookah would do an excellent job of dispersing the necessary smoke chemicals into water but getting the required chemicals in the compound to be burnt would be a problem. I doubt that tobacco or any one plant smoking mix would have the spectrum of chemicals for the cocktail produced from a bush or forest fire. A damp gauze placed over the chimney of a woodfire may work.

I seem to recall that Australian researchers have recently identified the main chemical responsible but I believe this is still under investigation & not available commercially for some time.

I use the Smoke Primer paper myself then place the seed on top of the seed-raising medium, then cover with a thin layer of fine ash/charcoal I've saved from my winter woodfires before placing a fine layer of propagation sand on top of that & then misting.  If anyone wants to try these Smoke Primer papers, please let me know.

Geoffrey Barnier
Coffee Camp, NSW, Australia

PS  I don't have Humming birds here but rather my nectar eaters are Noisy Minors & Rainbow Lorikeets mainly. They generally leave my Hippies & Naked Ladies & such like alone & prefer their native flowers of gravillea, etc. Something has been taking the flowers of my Fringe Lily all away though on the day its bloom opens. Had to put it out of harm's way as I want its seeds.


 


More information about the pbs mailing list