In the lungs bronchial aeries supply the bronchopulmonary tree:

Lower lobe of both lungs has 5 segments - superior, anterior/ posterior/ medial/ lateral - basalQ. Middle lobe of right lung has lateral & medial segmentsQ. Bronchopulmonary segment is drained by intersegmental pa of pulmonary veinQ that lie in intersegmental space and drain adjacent segmentsQ. Bronchial aeries supply the bronchial wall as for as the respiratory bronchiolesQ, beyond which it is supplied by branches of pulmonary vessels. Bronchopulmonary segment Bronchopulmonary segment is respiratory unit. Each B.P. segment has - Pulmonary aeriole, Broncheal aery & Bronchiole Pulmonary vein lies in inter segmental spaceQ; so during segmental resection surgeon work along pulmonary vein. Bronchopulmonary segment is not a broncho-vascular segmentQ, because it does not have its own vein. Each segment has more than one vein & each vein drains more than one segment.