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In 1995, significant damage caused by Xylosandrus germanus (Blandford) was reported on round timber, both with bark and decorticated, of Norway spruce and fir. The insecticides used against Xyloterus lineatus and Hylecoetus dermestoides (L.), showed an insufficient to no effect againstX. germanus. Between 1996 and 1998, the development of the populations were investigated, the effectiveness of insecticides tested and the influence of felling date, decortication and storage site investigated in correlation with the intensity of damage. The decreasing population density, the activity of the insects as well as recommendations for felling and removal of round timber are illustrated and discussed.

In den Jahren 1992 und 1993 wurden 24 schwarzeTheysohn-Schlitzfallen mit Kombinationen von synthetischen Borkenkaferlockstoffen, Pheroprax, Chalcoprax, Linoprax und Cembrax, auf ihre Fangigkeit getestet. Zum Vergleich wurden Fallen mit Einzelbestuckung und Zweifachkombinationen von Pheroprax+Cembrax und Linoprax+Cembrax sowie zwei Fallen ohne Lockstoff in einem 24 ha grosen Forstgebiet aufgestellt. Mit den Fallen wurde die Flugaktivitat der angelockten Scolytiden ermittelt. Die erhaltenen Fangzahlen vonIps typographus, Pityogenes chalcographys, Xyloterus lineatus undX. domesticus wurden wochentlich registriert und in Verbindung mit der unterschiedlichen Pheromonbestuckung der Fallen diskutiert. Von den drei letztgenannten Arten wurde der Fang von Mannchen und Weibchen getrennt bewertet.

Research was carried out in High Tatra and Low Tatra Mountains in 2009. It was aimed to compare the efficiency of two types of pheromone traps (Lindgren funnel trap and Theysohn trap), two types of lures (Ipslure and Pheroprax A) to control the spruce bark beetle (Ips typographus), characterize flight activity pattern of I. typographus and identify bark beetle species caught in traps. Altogether 40 traps were set up for bark beetles (16 traps in Low Tatra Mountains and 24 traps in High Tatra Mountains). Lindgren funnel traps yielded higher catches of I. typographus (by 18.2% on average) than Theysohn traps, although this was not statistically significant (p > 0.05). The traps baited with Pheroprax A caught a total of 3,833 individuals of I. typographus per trap, those baited with Ipslure 1,587 individuals per trap. In this particular case, the difference in the bark beetle catches between the two lures was statistically significant (p < 0.05). The flight pattern of I. typographus in both mountain areas was similar. It showed great decrease in abundance of flying individuals of I. typographus as a result of low temperatures in the middle of June. Flight patterns of the bark beetle in the two mountain areas were similar to those documented from other sites monitored in Slovakia over the growing season 2009. Altogether 25 bark beetle species (22 species in High Tatra Mts., 18 species in Low Tatra Mts.) and 1,066,494 individuals were caught. I. typographus was the dominant scolytid species in traps (over one million adults caught). Other important (abundant) bark beetles included Pityogenes chalcographus (15,914 adults), Xyloterus lineatus (2,008 adults), Dryocoetes autographus (308 adults), Hylastes cunicularius (421 adults), Hylurgops palliatus (227 adults), Orthotomicus laricis (77 adults), Crypturgus cinereus (76 adults), Polygraphus poligraphus (45 adults), followed by other less abundant and less important bark beetle species.

The incidence of subcorticolous and xylophagous beetles (Coleoptera) on 11 conifers (including introduced species) was tested in a model area in southern Bohemia by means of tree and window traps. The most infested conifers were spruces and pines. The highest dominance among the bark beetles was found in Pityogenes chalcographus (L.) averaging 48% on all the conifers, and Xyloterus lineatus (Ol.) averaging 18%. Ips typographus (L.) was dominant on the spruces (Picea spp.) (average dominance 41%), Pityokteines spinidens Reitt. on firs (Abies spp.) (average dominance 47%) and Myelophilus piniperda (L.) on pines (Pinus spp.) (average dominance 36%). Zusammenfassung Untersuchungen zur Attraktivitat und Eignung nicht-heimischer Koniferenarten fur holzbewohnende Kafer Das Vorkommen rinden- und holzbrutender Kafer an 11 Koniferenarten, darunter auch nicht-heimische Arten, wurde in einem Versuchsgebiet im sudlichen Bohmen mittels Fangbaumen und Fensterfallen untersucht. Am haufigsten wurden Fichten- und Kiefernarten befallen. Die groste Dominanz unter den Borkenkafern wies Pityogenes chalcographus (L.) auf, mit durchschnittlich 48 % an allen Koniferen. An zweiter Stelle, mit 18 %, stand Xyloterus lineatus (Ol.). Ips typographus (L.) war an den Fichtenarten (Picea spp.) dominant (durchschnittlich 41 %), Pityokteines spinidens Reitt. an Tannen (Abies spp.) (durchschnittliche Dominanz von 47%) und Myelophilus piniperda (L.) an Kiefern (Pinus spp.) (durchschnittliche Dominanz von 36%).

Na širem području Risnjaka, na 11 lovnih lokacija u tipičnim šumskim zajednicama Gorskog kotara obavljeno je tijekom 2001. godine motrenje pojave i oscilacije populacija potkornjaka. Sabiranje rojećih potkornjaka obavljeno je naletnim barijernim klopkama tipa THEYSOHN® opremljenim poznatim feromonskim pripravcima za lov smrekinog pisara (Ips typographus L.) i crnogoričnog ljestvičara (Xyloterus lineatus Oliv.). Dodatno, u ulovima je posebno izdvajan i bukov ljestvičar (X. signatus L.). Rezultat pregleda 184 pojedinačnih ulova (prosječno 18 lovnih uzoraka po svakoj lovnoj lokaciji) je 114927 jedinki potkornjaka izdvojenih pojedinačno i ručno prebrojanih. Do razine vrste determinirane su slijedeće vrste potkornjaka: crnogorični ljestvičar – 97196 jedinki, bukov ljestvičar – 12450 jedinki i smrekin pisar – 5281 jedinki. Među gotovo 100000 ulovljenih i determiniranih primjeraka potkornjaka nije potvrđen niti jedan nalaz Xyloterus laeve Eggers vrste relativno nedavno otkrivene u sličnim feromonskim ulovima na području središnje Europe. Temeljem rezultata provedenog istraživanja pretpostavlja se da južnije od područja Risnjaka i istraživanog dijela gorske Hrvatske ova vrsta ne pridolazi. U radu se komentira sezonska dinamika motrenih populacija potkornjaka, njihovi relativni kvantitativni odnosi prema visinskoj i prostornoj razdiobi lokacija ulova. Razlike se objašnjavaju osobitostima samih lokacija, njihovim ambijentalnim obilježjima kao i blizinom ili udaljenosšću od sastojina u kojima se provode gospodarske mjere. Također, ukupni godišnji ulovi smrekinog pisara uspoređuju se sa ulovima ove vrste dobivenim kroz redovni posao motrenja koje provode djelatnici UŠP Delnice iz čega se zaključuje da su ulovi na ovim lovnim pozicijama višestruko veći od onih dobivenih unutar granica NP „ Risnjak“ . Zbunjuje međutim činjenica da su najmanji ulovi u gospodarskim sastojinama čak četverostruko niži od najvećih ulova u gotovo prašumskim sastojinama u središnjem masivu Velikog Risnjaka. Zaključuje se da samo na temelju ovako prikupljenih podataka nije moguće utvrditi koje su populacijske razine kritične, odnosno kada predstavljaju opasnost za sastojinu u kojoj se pojave. Provedena metoda je svakako dobra osnova za nastavak motrenja i može poslužiti kao odličan praktični oslonac za uvođenje jedinstvene metode motrenja na razini države.