I have to voice strong agreement with and support for the content (not the tone or manners) of Sequoia-named-guy in this thread. There is a choice to be made between conserving and adapting. Unfortunately both approaches involve risks that are hard to quantify. At this point it is more difficult to argue the dangers of inadvertent introduction of pests because the damage seems to be pretty much done. One sees too many non-profit organizations panhandling for the cause without advancing it. Example, American Chestnut Foundation. Its corporate existence ends the day it succeeds in breeding resistant timber-worthy trees, a goal that should be in easy reach but somehow takes centuries. Our "scientific leadership" in this area includes people who are happy to shrug off the elimination from eastern USA forests of hemlock and ash without really worrying about it: Ellison himself is dealing with the hemlock woolly adelgid, which is killing all the hemlock trees on his own 100 acres in western Massachusetts. But Ellison plans on just letting his trees all die and seeing what comes next. “I’m leaving it alone,” he said. “I suspect it will become a black birch forest and after that I have no idea.” Ellison holds an adjunct appointment at Harvard and so gives credibility to Pennsylvania's laissez-faire forestry. One really has a hard time swallowing the ban on Fitzroya seeds. Chile and Argentina want to keep their tree a national monument that cannot be observed anywhere else in the world. Conservation groups buy into it and put out glossy brochures and support the (doomed) status quo.

I also think it would be almost impossible for DEFRA to compile a list, they cant even get a website to work correctly. I may have received a partial list which i obtained from an email reply from The Scottish Government regarding this issue, it is no longer DEFRA who deals with the banned and permitted list it has been taken over by FERA (Food and Environment Research Agency) who have a link to http://www.kew.org/conservation/cites-slidepack.html where it advises on some plants and seeds which are banned or restricted and who can import them. It also gives information that states seeds from EU countries can be freely brought in to the UK by travellers but in limited amounts as long as they are for personal use and not for commercial use. There was 2 reasons i was looking for a list, 1 = I saw wild cucumber plants with pods in Poland and liked the plant and pods but never collected any as i thought it was illegal to bring any wild picked seeds/plants into the UK and on another forum i was advised by an american man who had them growing near to him, as i live in the UK he could not send any and i assumed it was on a banned list. 2 = Some species of plants are classed as endangered in the wild therefore it is illegal to remove them from their natural habitat but wondered if someone who had one of the plants growing in their home from before the said plant was added to the CITES list and had collected seeds could they trade or gift seeds to someone in the UK or indeed any country legally. ( This is also refered to in the list above). I am going to research the information and see if i could compile a list of definate no-no`s and possibles. Thanks for your reply Steve

First of all, whether it is important to any specific gardener depends on at least (and not limited to) 3 factors... 1 - The climate of the garden... 2 - The tolerance factor of the gardener... 3 - Expectations of taste, yield, and seed saving... If you live in an area that has summer time temperatures and humidity/moisture levels enjoyed by fungi and bacteria... then it will automatically be of a higher concern. Even in areas with good average climates there will be years where the weather will just work against your efforts. In such cases, does a specific gardener have a 'zero tolerance' factor for diseases? That tolerance factor will also be affected by how much work and time the gardener can, or wants to, devote to prevention and eradication. Another question along these lines is - to what level of chemical-free the grower aspires? Having zero-tolerance, and not wanting to use chemicals (even organic ones) is pretty much unreasonable. The other question that forms at this point is whether the gardener is willing to sacrifice some taste, yield, or seed saving (along with other favorable characteristics) in their efforts to fight disease, balanced with their need or desire to devote less time and effort, and their wish to not use sprays. Finding the right varieties that fit into *at least* these 3 conditions is a reasonable effort to make for anyone aspiring to be successful at having their own tomato crop. At the bottom of this pdf from our local University Extension (UT) there's a fairly good list of varieties and their disease resistance. Of course it isn't comprehensive, and it is geared to our local growers and climate, but tomatoes are big business here, and these are selected varieties. It is no substitute for time spent leafing through catalogs and the experiences of other gardeners, but it can be a good starting point... especially for commercial growers. https://extension.tennessee.edu/publications/Documents/SP370-C.pdf

"But I wouldn't be surprised if that red mistletoe has some specific climatic needs that is hard to meet in other parts of the world." Oh, definitely. I was of course being facetious to imply it could be hawked by the likes of Wayside Gardens to people in Peoria, KS. Though it would probably grow, on the right substrate, somewhere along the west coast of the US. I think it's harder to import seeds to NZ than export from there. Increasingly countries are moving towards various 'biodiversity protection' laws where the flow of genetic material of native plants outwith the country is tightly regulated, particularly anything considered threatened or vulnerable. I don't know if NZ has such a law yet, but they could. The is related to the Nagoya Protocols, the effect of which I've vaguely alluded to in various posts of mine. Can't be too specific, but suffice it to say million-dollar breeding programs have had to have years of work tossed in an incinerator because of legal wranglings between countries - insanity!