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Bukva predstavlja jednu od najvažnijih vrsta drveća u Bosni i Hercegovini. Stoga, potrebno je praćenje zdravstvenog stanja bukovih sastojina i poduzimanje svih neophodnih preventivnih i represivnih mjera kako bi se zdravstveno stanje ovih sastojina unaprijedilo. U okviru istraživanja analiziran je utjecaj bukove skočipipe na površinu oštećenja listova na stabalcima bukve od imaga i ličinke u ovisnosti od lokacije i položaja stabalaca bukve u sastojini (svjetlo/sjena). Lokacije istraživanja su se nalazile unutar kulture smreke, visokih šuma bukve i mješovitih šuma bukve i jele sa smrekom. Bukova skočipipa predstavlja jednog od glavnih defolijatora koji se javljaju na stablima bukve. Uzorak istraživanja čine 15 stabalaca bukve, po 5 stabalaca na tri lokacije. Na svakoj lokaciji odabrana su 3 stabalca čija krošnja je bila na svjetlu i dva stabalca čija krošnja je bila u sjeni (ukupno 9 stabalaca na svjetlu i 6 stabalaca u zasjeni). Na svakom stablu pregledavana su i mjerena oštećenja od imaga i ličinke bukove skočipipe. Ustanovljeno je da prosječna površina oštećenja lista bukve od imaga je varirala od 2-4%, a ličinke od 4-8%. Statističkim analizama je utvrđeno postojanje statistički značajnih razlika u površini oštećenja lista bukve od ličinke u ovisnosti od položaja stabalaca bukve u sastojini., The impact of beech weevil on the damaged area of beech trees from adult and larvae was analyzed, depending on the location and position of trees of beech in stand (sun/shadow). The research localities were located within the forest plantation of spruce, natural beech forests and mixed beech, fir and spruce forests. Beech weevil represents one of the main defoliators appearing on beech trees. The research sample consists of 15 beech trees, 5 trees per location, on three locations. On each location, were selected 3 trees with the crown in the sun and 2 trees with the crown in the shade (a total of 9 trees in the sun and 6 trees in the shade). On each tree were measured damages from the adult and larvae of beech weevil. It has been found that the average damaged area on beech leaf varied for adult from 2-4%, and larvae 4-8%. Statistical analysis showed a statistically significant differences in damaged areas of beech leaf from larvae, depending on the position of beech trees in the stand.

Investigations on the flight and flight behaviour of curculionids. Detail investigations were made to determine the flight of curculionids using Moericke- and window-traps in an area in middle Hessia. The results show that the main flight period occurs during May and June, although some species fly during late summer and autumn. During the day, most species fly around noon and in the afternoon; flight before 8 a.m. and after 5 p.m. is rare. Night flight was not detected in any species. During the specific flight period, each species has a certain lower temperature threshold. In these investigations the values were 9° C for Rhynchaenus fagi, 10° C for Apion virens and A. flavipes, 15° C for Phyllobius maculicornis and 20° C for Sitona sulcifrons. At temperatures above 27° C a general decrease in flight activity could be stated. The ratio of ♂♂ to ♀♀ was mostly 1:1. In some species, however, greater differences were noticed though in the cultures there were equal numbers of each sex. Catches in yellow Moericke-traps were nearly four times as great as in blue, green and white ones. Catches in traps at different heights suggested that most curculionids (except Ceutor-hynchinae) flew over legume fields at a height of greater than 1 m.

Prikazujemo šest vrst žuželk in eno vrsto pršice, ki se relativno pogosto pojavljajo na listih navadne bukve (Fagus sylvatica). Bukova kobilica (Miramella irena) se periodično pojavlja v gradacijah na določenih lokacijah, prav tako bukov rilčkar skakač (Rhynchaenus fagi), bukova uš (Phyllaphis fagi)je vedno v nizki gostoti populacije prisotna v sestojih bukve, sledi prikaz metulja zavrtača bukovih listov (Phyllonorycter maestingella) ter dveh vrst muh, ki povzročajo nastanek zoocecidijev na zgornji listni ploskvi navadne bukve (Mikiola fagi, Hartigiola annulipes). M. fagi in H. annulipes spremljata areal navadne bukve pri nas. Prikazujemo tudi pršico (Aceria nervisequa nervisequa), ki je povsod, kjer je se pojavlja gostitelj, pogosta je tudi v urbanem okolju. Na kratko je prikazana njihova morfologija, bionomija, opis poškodb, morebitne zamenjave, gostitelji, najpomembnejši naravni sovražniki ter ogroženost sestojev. In the present contribution six insect species and one mite species which are relatively common in our forests are presented. On several locations outbreaksof Miramella irena were noted, likewise of the beech weevil (Rhynchaenus fagi). The woolly beech aphid (Phyllaphis fagi) is always presentin beech stands in low abundance. The next insects presented are the butterfly - leaf miner (Phyllonorycter maestingella) and two species of flies (Mikiola fagi, Hartigiola annulipes) which cause zoocecidias on the upper partof beech leaves. The latter two species frequently accompany our beech stands. The mite species (Aceria nervisequa nervisequa) is also presented, which often appears on European beech, also in urban areas. A short description of the insects' and mites' morphology, bionomy, a description of damage, possible misidentifications, hosts, the insects' and mites' most important natural enemies and the threat to forests are given.

The relationship between supercooling and survival of the beech leaf mining weevil, Rhynchaenus fagi was examined in exposures at constant temperatures between +10 and −15 °C, and in cycling regimes. Similar observations were made on naturally overwintering field populations. No weevil survived cooling to, or below the supercooling point. The mean supercooling point of weevils exposed to temperatures at, or below +2 °C, or sampled from the field, was consistently below −21 °C. When exposed to a constant +2 or −5 °C, mortality was low, at 10 and 12% after 168 and 126 days respectively. Mortality increased rapidly in weevils exposed to temperatures below −10 °C, with 48% survival after 112 days at −10 °C and only 25% after 84 days at −15 °C. None of the dead weevils had frozen. Periods spent at +2 °C in cycling treatments which included exposure at −10 or −15 °C, extended the duration of survival at the lower temperatures compared to constant exposures at these temperatures, but mortality was still more rapid than at a constant +2 °C. Survival of naturally overwintering insects was consistently high over three winters.

The effect of ambient air pollution with increased ozone concentrations on the feeding behaviour of the beech weevil Rhynchaenus fagi L. was studied. In a dual choice feeding test the beech weevil preferred leaf disks from beech saplings exposed to ambient air against those from filtered air in 65.5% of all cases.

The developmental stages of the beech weevil, Rhynchaenus fagi L. are proposed as suitable material on which to base a practical study on some aspects of population dynamics. The life history of the weevil is explained, illustrating the convenience of the immature stages for the study of development and mortality in a population. The factors normally causing mortality during each of the developmental stages are described. Results obtained from the collection of a random sample of infested leaves are included as an example of the simplicity with which data can be obtained to illustrate the concept of the life table. The limitations of such a study as well as the possibilities for changing emphasis are briefly discussed.

1. Overwintered and starved weevils fed on beech within 5 min of contacting the plant in spring, and oviposition occurred in less than 48 h after feeding. 2. Size of unlaid eggs was significantly reduced when feeding weevils were subsequently starved from beech for 3 days. 3. Date of bud burst did not affect the amounts of feeding or oviposition by weevils. 4. Weevils fed and oviposited preferentially among trees, and the same trees were preferred in two successive years. This preference was independent of bud burst date.

1. The annual cycle of reproduction of Rhynchaenus fagi was found to involve a female reproductive diapause of the short day-long day type. 2. Males were sexually mature soon after emergence. 3. The diapause was terminated by 8–12 weeks of a short day followed by 4 weeks of a long day; weevils were not sensitive to the treatment immediately after emergence. 4. Diapause ended in the field in mid-March but was terminated in the laboratory two months earlier. 5. The diapause condition synchronized egg development with the new growth of beech leaves.

1. In laboratory experiments, R.fagi made feeding holes in eighteen tree and shrub species, including beech, from seven plant families but few plants other than beech were eaten to any extent. 2. Overwintered adult weevils preferred beech to all these eighteen plants in spring. 3. Hawthorn and raspberry were the most acceptable plants if beech was not available at this time. 4. Field collected weevils from hawthorn had partly developed oocytes in early April, prior to beech bud burst. 5. New generation weevils sought alternative food sources in late June and July; raspberry was preferred to the youngest available beech leaves at this time.