One misleading statement that appears on many internet pages is Ragwort has a germination rate of 70%. It is often paired up with the other misleading statement about the number of seeds that ragwort produces. Together these are framed to produce the effect that somehow this adds to its danger.
The 70% figure is probably reasonably accurate. There is nothing extraordinary about this at all it is a fairly typical figure for many plants under laboratory conditions. However it is absolutely useless in telling us anything about the plants spread or success. Germination rate is not the figure you want to look at. The very obvious fact is that on average, one plant will produce one offspring.
We also know that the seeds do not spread far. Normally only a matter of metres at most. . See ragwort- how far do the seeds disperse.