evaluation of pinus eldarica hazardous criterias in the babol city (mazandaran province, northern state of iran)

Any defects in street trees may cause injuries to human, vehicles and buildings. this research was investigated in the babol city, mazandaran province, in the northern state of iran.used the perfect inventory methods and measured the diameter at breathe height (dbh), height and hazardous criteria (dead woods, cracks or seams, decay, wound or cankers, root problems, weak branch unions and skew from vertical line). in each hazardous criterion classes compered the slenderness (h/d); height (m) and diameter at breathe height (cm). the means of different between slenderness (h/d), height (m) and diameter at breathe height (cm) in the hazardous criteria classes were estimated by anova test. data analyzing was done by spss16 software. results showed that the mean of dbh and h/d in the hazardous class (class one) was higher the other classes in the seven hazard criteria, but mean height of tree in the class 3 (non-hazard classes) was higher quantity. results showed that the different between three classes of hazard in the seven hazard criteria was significant. overall results showed that the hazardous class (class one) has a higher h/d quantity and more hazardous potential.