Probability model of sessile oak (Quercus petraea (Matt.) Liebl.) stump sprouting in the Czech Republic

We modeled the probability of sessile oak (Quercus petraea (Matt.) Liebl.) stump sprouting 1 year after harvest. We established seven research plots in forest stands with ages from 31 to 97 years, differing site indexes and elevations ranging from 290 to 410 m above sea level. A total of 862 stumps of sessile oak were analyzed. In each plot, the position (respective to the plot centre), stump surface diameter, age at the time of harvest and regeneration status (successful or unsuccessful) were determined for every stump. The probability of stump sprouting 1 year after harvest was modeled using logistic regression. Stump diameter and parent tree age were both negatively correlated with sprouting probability. No impact of site index on sprouting probability was found. Out of several analyzed models, three models were statistically significant. The model with stump diameter was found to be the most suitable. For stump diameters ≥35 cm, the sprouting probability fell below 50 %. For stump diameters up to 20 cm, the probability of at least one living sprout occurrence was ≥70 %. When compared with similar models used for three North American oak species (Quercus velutina Lamb., Quercus montana W. and Quercus alba L.), the sprouting probability in sessile oak stumps declines more sharply as stump diameter increases.