Hi everyone, I only just joined ATP a few days ago and am still figuring out how everthing works but notice a few familiar names here from Tinkers and the AHS Robin. I created the spring sickness website (the one that also includes the image gallery Tink mentioned,
http://web.ncf.ca/ah748/sstf.h... ) on behalf of the informal "spring sickness task force" and may be able to answer some questions. (The web site does need some minor updating but as Tink said it is still mostly up to date largely because we've kind of got stuck on proving the extent, or not, of the involvement of bulb mites in the different aspects of spring sickness).
I'd like to mention that the second site that was mentioned further up the thread isn't entirely accurate and sounds rather alarming! I think perhaps the spring sickness task force site has been misinterpreted because we're the ones who initially suspected bulb mites as being involved (although there was a Polish study that we found afterwards which describes something similar to ss in daylilies and also attributes it to bulb mites). A study at Ohio State U also proposed that the leaf streak fungus could be involved. The reason we started looking for pests is that the leaf streak fungus is believed to need an entry point such as pest damage to get into the plant. The damage of spring sickness on daylilies is very similar to that described as bulb mite injury on other plants and they tend to be associated with fungi.
Currently what we are working on is that bulb mites, the leaf streak fungus (Aureobasidium microstictum) and environmental conditions may combine in some way to cause the disorder, which starts before the fans emerge in spring. It's also possible that there is another missing factor, maybe another pest that starts the bulb mites off. One task force member has had some improvement in spring sickness by experimenting with fungicides and insecticides/miticides but didn't entirely eliminate it. We wrote this up in the Daylily Journal - it's also available in PDF on the AHS web site members only section, Journal archives.
Anyway, back to the "Decadent" article - spring sickness is not "a dangerous plant disease". It is also not an "emerging disease", it's been around since at least the 1950's, maybe even longer than that, and probably isn't solely "a disease". While it can affect a whole clump, it won't spread from one or two fans to affect the whole clump if untreated, as suggested. In fact a clump may have one or two fans or all affected in any given year and not have any spring sickness at all the next. The randomness, inconsistency, and full year between events makes it very difficult to study.
I hope this clarifies a few things. If there are any other questions I'd be happy to try and answer them.
There are a few more pictures of spring sickness in the AHS Daylily Dictionary here:
http://www.daylilies.org/ahs_d...
OK better stop now, this is getting rather long for a first effort!
Sue
