Raziskava pomembne entomofavne hrastovih gozdov Slovenije

Insects in 9 research areas in pedunculate oak and sessile oak forests in Slovenia have been studied. We identified 35 insect species as well as two genera from 13 families. The defoliation of oak leaves in studied forests was between 10 and 90 %. More than 80 % of the defoliation was caused by mottled umber and winter moth (Erannis defoliaria Cl., Operophthera brumata L.). Leaf-roll moths are an important group of pests of oak leaves and acorns. The most numerous is the green leaf-roll moth, Tortrix viridana L., followed by Archips crataegana Hb., Laspeyresia splendana Hb. and Laspeyresia amplana Hb. The ratio of appearance of oak sawflies (Apethymus abdominalis Lep. and Apethymus braccatus Gmel.) was 9 : 1. During the past 10 years, oak miner (Tischeria complanella Hb.) has attacked young oak trees heavily. Acorn destroyers (Balaninus glandium Mrsh. and Balaninus nucum L.) were important acorn pests. During the gradation of defoliators in the Prekmurje region of Slovenia there was an increased population density of their predators, such asground beetles and burying beetles (Calosoma sycophanta L., Calosoma inquisitor L., Carabus spp., Xylodrepa quadripunctata L. We can confirm that the health of oak forests in Slovenia is better than in Croatia and southeastern Europe.Na devetih raziskovalnih ploskvah v dobovih in gradnovih gozdovih v Sloveniji smo proučili entomofavno. Določili smo 35 vrst žuželk ter dva rodova iz 13 družin. Defoliacija hrastovega listja je bila 10 do 90 %. Več kot 80 % defoliacij sta povzročila veliki in mali zimski pedic (Erannis defoliaria Cl.,Operophthera brumata L.). Zavijači so pomembna skupina škodljivcev hrastovega listja in želoda: najštevilnejši je bil zeleni hrastov zavijač - Tortrix viridana L., sledili so mu Archips crataegana Hb. ter vrsti Laspeyresia splendana Hb. in Laspeyresia amplana Hb. Razmerje pojavljanja pozne in zgodnje hrastove grizlice (Apethymus abdominalis Lep. in Apethymus braccatus Gmel.) je bilo 9 : 1. Miner hrastovega listja (Tischeria complanellaHb.) je v zadnjih desetih letih močno napadal hrastov pomladek. Hrastov semenar (Balaninus glandium Mrsh.) in leskov semenar (Balaninus nucum L.) sta bila pomembna elodova škodljivca. V Prekmurju je bila v času gradacije defoliatorjev povečana gostota populacij njihovih predatorjev, kot so krešiči in mrharji (Calosoma sycophanta L., Calosoma inquisitor L., Carabus spp., Xylodrepa quadripunctata L.). Prisotnost predatorjev po gradaciji gosenic defoliatorjev je kazala na dober mehanizem regulacije naravnega ravnovesja v sestojih. Na osnovi analize lahko trdimo, da je zdravstveno stanje hrastovih gozdov v Sloveniji boljše kot na Hrvaškem ter v jugovzhodni Evropi