Results/Conclusions

We found no significant differences in seed fate between the habitats.  There was a wide range of germination in the first year, from 13% to 98%.  Fewer than 0.01% of the seeds were lost to decomposition.  Thus, the percentage of seeds remaining viable entering the second winter of the study ranged from 2 to 87.  We used this data, along with results from other experiments and published literature, to parameterize a subperiodic matrix population model of M. vimineum. Preliminary analysis shows that variations in seed bank parameters do not play a very large role in population persistence under normal conditions.  The model was most sensitive to fecundity and to the probability of new seeds germinating and surviving to reproductive age.  These were also the most important population parameters in a simulation of population growth including varying frequency of control events with almost complete suppression of seed production.  However, the model with control was much more sensitive to frequency and timing of control events than to any population parameter.  These results suggest that reducing fecundity is the most effective management strategy.