Lots of factors, i grew up riding on wet roots so they dont tend to phase me much (but i still fall off on them from time to time).
First things first, doesnt make as much difference as some while tell you on what tyres youve got, nothing is gonna grip so a wet shiny bastid fat bastid root, whats worth remembering though is that the faster your travelling the less time your tyre has to ‘slip’ on said root. Adjusting your line so your heading into them as square on as possible allows you to go much faster too (even if this might not be the fastest line in the dry).
The hardest ones are big massive bundles of off camber roots, (which unfortunatly seems to how the usually are :D) if its a short enough section then if your confident enough then yes, jump the whole section and keep on it, however when this isnt possible, simply ‘unweighting’ the bike as you head over the worst of it often allows you to carry more speed, stay relaxed stay off the brakes and get ready to try again when you fall off practicing 😀