Assessing long-term risks of prairie seed harvest: What is the role of life-history?
Extinction risk, Grasslands, Life history, Matrix models, Seed harvest, Tallgrass prairie
To meet the demand for more and larger tallgrass prairie restorations, seed is frequently collected en-masse from remnant native plant populations. Overharvesting of seed may lead to population extinctions, but these risks are not well studied. Species’ reproductive strategies may provide a basis for risk assessment. We assessed extinction risks associated with seed harvest for grassland plant species with different reproductive strategies (clonal vs. non-clonal). Using stage-based matrix models, we projected the extinction risk for two clonal and four non-clonal prairie species subjected to five harvest scenarios: (i) no harvest, (ii and iii) annual harvest at low/high intensity (50% and 75% seeds removed), and (iv and v) triennial harvest at low/high intensity. We compared the magnitude of growth or decline (λ) and mean extinction risk among populations during a 25-year modeling period. Non-clonal species were robust to triennial and low-intensity harvest, but susceptible to decreases in population growth (λ) up to 0.5 and elevated extinction risks up to 95% with high intensity annual harvest. Clonal species were unaffected by seed harvest, owing to a compensatory effect of vegetative propagation on growth rates. To maintain populations of non-clonal species in remnant grasslands, high intensity annual harvest should be avoided.
Tallgrass Prairie Center
Original Publication Date
DOI of published version
UNI ScholarWorks, Rod Library, University of Northern Iowa
Meissen, Justin C.; Galatowitsch, Susan M.; and Cornett, Meredith W., "Assessing long-term risks of prairie seed harvest: What is the role of life-history?" (2017). Faculty Publications. 962.