Kaitsetara kasutamise efektiivsus ulukikahjustuste vältimiseks männikultuurides

Eestis on puistutest suurim osakaal männikutel (34,4% pindalast) ning nende põhilisteks kahjustajateks on hirvlased. Töö eesmärgiks oli uurida kui palju aitab kaitsetara vähendada ulukikahjustusi männikultuurides ning selle võrdlust teiste kaitsemeetmetega.Töö toimus raiesmikul, mille ühele poole oli kaitsetara ümber ehitatud. Nii tarastatud kui ka tarastamata alal asusid 8 proovitükki.Töös selgus, et aias esines küll kahjustusi kuid need puud olid kahjustatud juba enne kaitsetara ehitamist. Peale aia ehitus polnud puid rohkem kahjustatud. Aias kasvanud puude kahjustusprotsent (15%) oli kõigil liikidel väiksem kui aiata alal (60%). Veel selgus aia mõju keskmisele puudearvule hektaril ja puude keskmisele kõrgusele, seda eriti männi puhul. Puude arvukus oli kaks korda suurem aias kui väljas ning keskmine kõrgus oli samuti peaaegu kaks korda suurem aias.Analoogseid pole Eestis varem teostatud. Kindlasti vääriks uurimist kaitsetarade majanduslik tasuvus erinevates kultuurides, ning kaitseaedade ehituslikud erinevused (kas on traatvõrgust, mis postid oleksid parimad, kas saaks ainult puidust ehitada, vastupidavus).

English. In Estonia, the largest part of forest stands is constituted by pine stands (34.4% of surface area) and the main pests for pine stands are cervines. The objective of the paper was to find out how much does a fence help to reduce damage caused by game in pine cultures, also in comparison to other defensive measures.The damages were studied at a clear cut area, which was surrounded with a fence on the one side. Both the fenced and not fenced area had 8 test plots.Study revealed that there were damages inside the fence, but these trees had been damaged already before the fence was built. The percentage of damages in all species of trees inside the fence (15%) was lower than on the fenceless area (60%). Also the impact of the fence on the average number of trees per hectare and the average height of trees was specified, especially for pines. The count of trees was twice as high and the average height was also nearly twice as high for the pines that grew inside the fence. Similar studies have not been conducted in Estonia before.Certainly it would be worth to study the economical cost-effectiveness of fences for different cultures and the constructional differences of fences (is using wire-net the best option, what kind of posts would be the best, could fences be built only of wood, durability).