Abstract 

In this study which constructed in Artvin in 2010-2011, the distribution status, biology and damage of Horizontal Gear bark beetle (Pityokteines spinidens) which damaged in Abies (Abies nordmandiana) Forests in Artvin was tried to bring out . Besides  it  prefers to be host trees Picea, Pinus and Abies in Artvin, ıts harm in Abies forests is higher than other forests. This harmful damages Abies in high elevations,too much. In making research from the point of view of biological, it was detemined that being two generasyon in per year ; moreover the first flying time is at the  end of April and at the beginning of May, and that the second flying time is in July. The flying of insect usually depends on air heat. The flights starts with rising upon 16 centigrant of air heat but the insect doesn’t fly on closed and rainfalled air. The number of eggs left by female insect were counted as 32 per in 3-8 pieces of stellar roads in trees where it damaged. In investigations conducted in the region, It was determined that 50-70 age group of the trees were much more exposed to deterimend of Pityokteines spinidens . It was determined that Adults usually settled in upper and hill parts of trees, thin parts of branches and trunks, and they caused by desiccations in these places. Mecanical and biyotecnical struggle are maked opposite P.spinidens. 1-3 unit trap trees in secand-third age group are prepared in hectare as to insect density. Adults insects that came in trap trees are destroyed in larvae phase with bark peeled machine or with peeling barks of trees in depots outside of forest.

 It was determined that adults of Pityokteines spinidens  intensivily came in prepared trap trees in places where this pest caused by desiccations. In order to determine the intensity of P.spinidens, 30 pieces of pheromone traps were hung in three different heights. 1200 pieces of adult insects were collected from these traps. It was determined that adults of Thanasimus formicarius, Rhizophagus depressus and Rhizophagus dispar also fell besides P.spinidens.While Pityokteines spinidens doesn’t die trees on its own, ıt causes to get thin them. Thus it rises harm of other bark insects.