Quantifying success share and plant density of direct seeding of Douglas fir using a hurdle negative binomial regression model

Abstract In recent years, direct seeding as a means of stand establishment has experienced revival. Among other things it allows for an undisturbed root development and is assumed to be cost-efficient. While success factors have been worked out through numerous experiments, sound overviews failure in practice are scarce. With the goals (i) quantifying proportion (ii) extracting associated influencing factors, we conducted inventory seedings Douglas fir Northern Germany fitted hurdle negative binomial regression model data. The results reveal high variability plant density within, well between stands. We could attribute these differences, thus success, stocking degree shelter, seed amount age. shows both, precision accuracy, respects previous physical biological knowledge data-generating mechanisms.