According to one of those suplementary notes that the series creators release occasionally, Juraian trees have roots that extend into other dimensions, which is where they get their nigh-infinite power. In GXP, we are told that the fancy wooden structures around the central modues are power limiters and without them these ships would destroy (or at least devatate) planets with even a low-power shot. Power requirements aren't really an issue for these ships.
As Juraian trees supposedly lose their power when they sink their roots into a planet, I'm guessing there is something unusual about the soil in the ships. It may be pulled from some of those other dimensions accessed by the roots, or (as you speculated) created with the nigh-infinite power I covered above and possible lighthawk-wings-make-physics-cry dickery.
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No, I don't believe the world has gone mad. In order for it to go mad it would need to have been sane at some point.
As Juraian trees supposedly lose their power when they sink their roots into a planet, I'm guessing there is something unusual about the soil in the ships. It may be pulled from some of those other dimensions accessed by the roots, or (as you speculated) created with the nigh-infinite power I covered above and possible lighthawk-wings-make-physics-cry dickery.
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No, I don't believe the world has gone mad. In order for it to go mad it would need to have been sane at some point.