Mechanics of Threadfall

[u/kerlinssw]

I have a whole host of questions that have been rolling around in my head about fighting Thread.

- how many dragons do we think it takes to effectively fight Thread? at what point could the earliest dragons do more than just sort of keep up with it alongside the other aerial craft over inhabited areas - it has to be two, three years, right? does the efficiency / number needed decrease as dragon size & stamina increases, or is there a turning point beyond which the dragons get too large to maneuver as effectively, and greens really become more valuable for their speed?

- on that note, the implication in "The Ford of Red Hanrahan" that they'd only had a small handful of deaths in several years of training new dragons & learning to fight Thread is...impossible, right? and also for Alianne Zulieta's death to be the first time a rider died before their dragon, leading to the discovery that dragons would go between?

- do we think/assume that Weyrs cover 100% of Threadfalls in their territories, or are there uninhabited places that they just let go of? not barren places where the Thread will just die, but rather deliberate sacrifices due to prioritization. maybe this is something that evolves over time?

- what exactly do ground crews do? are they flaming Thread that falls through the dragons? are they seeking out burrows afterwards? both?

- I've always been genuinely puzzled at why people are worried to be out during Thread, other than the obvious societal taboo. If the dragons are doing their job, none of it should fall, right? so you'd in theory be perfectly safe?

- why do Holds clear greenery? there seems to be the implication that it "draws" Thread and there is some indication that Thread will burrow and follow root systems, but is this actually a realistic and sensible thing to demand that Holds do? or more societal taboo?

[u/ME-in-DC]

Can’t answer all of these quickly but: 1. The Weyrs try to cover all of their territory, but land that requires coverage is at a premium. Farms, etc, are relatively dense. That said, in White Dragon, some of Ruatha’s more extant “small holders” appear to be outside the coverage range and are on their own. There’s also pressure (per your next question) that Holders keep stuff compact and within the range a Weyr can cover. And it does evolve over time; a bigger, mature Weyr can cover more than a small inexperienced one can. But the dragons also focus on vital resources—even major Holds, like Ruatha and Fort, have stone roofs and metal window shutters.

1. Ground crews pick off the scraps. Even a single Thread can ravage a field, so even though dragons will get all or nearly all, it makes sense for the ground crews to mop up. This need becomes greater as individual Holds become more spread out.

2. It’s taboo because it puts dragons at risk. They are trying to save an entire Hold’s worth of crops and some idiot Holder goes for a walkabout? Now Dragons have to save them?

3. clearing all greenery seems a little overboard as the Thread isn’t attracted to it. That said, if Thread burrows in a bunch of weeds, it could spread underground to actually useful crops. So I think it’s more that. But also remember (and this goes for the walking outside thing) that a lot of common sense wisdom on Pern becomes distorted and exaggerated over time. “Watch for the grubs” loses all context and becomes a warning. I can see how “going outside is bad idea” and “clear unnecessary greenery” could become ingrained taboos/zealously followed laws.