Published online by Cambridge University Press: 20 January 2017
Spreading dogbane is an important weed of wild blueberry fields thatdecreases yields and hinders harvest operations. A range of experiments wasconducted to evaluate the impact of abiotic factors on dogbane seedgermination. Freshly harvested seeds were largely nondormant with viabilityranging between 67 and 84%. Prolonged exposure to light neither promoted norinhibited germination. Germination rates and total seed germination variedwith temperature and osmotic potential. Significantly fewer seeds germinatedat 5 C compared with 10, 15, and 20 C. There was a significant quadraticrelationship between dogbane germination and osmotic potential, withsignificant numbers of seeds germinating at levels as low as −0.5 MPa.Emergence rates declined exponentially with depth in the soil and as many as9% of seeds germinated but were unable to reach the soil surface. Resultsindicate that substantial seed germination in blueberry fields is possibleand primary dispersal without wind occurs over a very short distance.