Accretion cross-section diameter d_σ dependent on the pebble radius R_pebble for an Earth-sized planet at 1 AU with wind erosion (red) and without wind erosion (black). For large pebble radii, both cases converge to an accretion cross-sectiondiameter of about 0.5r_Hill, which is slightly below the theoretical value (blue line) for gravitational focusing (Safronov 1972). We assume that the underestimation is caused by the close encounters that can spiral on highly eccentric orbits onto the planet, but are registered as non-accreting events when they reach a large distance from the planet.