Strawberry Reservoir, Utah is an 8.000 acre lake at the elevation of 7,550 feet; it has a maximum depth of 52 feet and an average depth of 18 feet. The supply of cutthroat trout eggs used to replenish and distribute this trout throughout the state are taken from two spawning traps located on reservoir tributaries. Because it has not proven economical to raise cutthroat to a larger size than newly hatched fry, it is at this site they are planted. Because of competition, predation, and lack of space the planting back of fry to maintain the fishery and spawning run presents a serious problem. Tributaries are at carrying capacity from being closed to fishing and the reservoir supports a tremendous population of trash fish; mainly the Utah chub, Gila atraria (Girard); yellow perch, Perca flavescens (Mitchell); redside shiner, Richardsonius balteatus (Cope); mountain sucker, Pantosteus delphinus Cope; and dace. Rhinichthys osculus Cope. The rainbow trout, Salmo gairdneri Richardson. and the cutthroat trout dominate the game fish population. It has been the policy of the Utah State Department of Fish and Game to trap and artificially spawn spawn every possible fish, leaving most of the spawning ground unused. This cost, plus the unknown advantage, if any, of artificial over natural reproduction led to the study of the possibilities of natural reproduction for replenishment of the cutthroat trout in the reservoir.

Darbo tikslas: ištirti savaiminio žėlimo ypatumus pamiškės ir miško gilumoje esančiuose medynuose bei šalia esančioje nedirbamoje žemėje. Darbo objektas: Kauno rajono Dubravų kaime esanti 1,55 ha privati žemės valda, kuri 127 m ruožu ribojasi su Dubravos eksperimentinės – mokomosios urėdijos miškais, bei pamiškės ir miško medynais. Darbo metodai: Atrankiniai tyrimai atlikti Vaišvydavos girininkijos miškuose bei privačios žemės valdoje, vadovaujantis Miško atkūrimo ir įveisimo nuostatais (2008). Pamiškės bei miško medynuose ir žemės valdoje 2009 m. buvo išskirtos laikinos stačiakampės aikštelės (2x5 m). Jų skaičius priklausė nuo medyno ar sklypo ploto. Apskaitos aikštelėse nustatyta savaiminukų rūšys, skaičius, aukštis bei gyvybingumas. Darbo rezultatai: Privati nedirbamos žemės valda nuo Dubravos EMMU miškų užsisėjo Š ir ŠR kryptimi – 80 m atstumu nuo pamiškės ir nedirbamoje žemėje per 5 metus susiformavo geri (virš 5000 vnt/ha) miško žėliniai, išsidėstę netolygiai. Jų rūšinę sudėtį nulemia pamiškės medynų struktūra. Žėlinių kokybė priklauso nuo dirvožemio sąlygų. Bendras savaiminukų kiekis Nd augavietėje 24% didesnis nei Nc. Savaiminis žėlimas miške, miško gilumoje ir nedirbamoje žemėje nėra vienodas. Nedirbamoje žemėje vidutinis savaiminukų tankis – 9030 vnt/ha, pamiškės medynų pomiškio tankis – 2610 vnt/ha, miško gilumoje – 1250 vnt/ha. Žėliniuose geriausia plinta beržas, drebulė ir eglė. / The aim of the work – to investigate self-growth forest peculiarities in the forest edge, the forest in the depth stands and nearby in the abondaned land. Object of the work – private land situated in 1,55 hectares of Kaunas district Dubrava village that 127 m boarders by strip adjacent to the Dubravas Scientific Experimental – forest enterprise and forest edge and forest stands. Methods of the work – selected studies were carried in Vaišvydavos forests district and non use land holdings in accordance with the restoration and establishment of Forest regulations (2008). Temporary accounting lots (2x5m) were created in 2009 year in forest edge of the forest stands and in private land holding. Their number depends on whether the stand of the total area.In the temporary accounting lots damage of the number of natural saplings, the spacies,ascertaining their mean heighand vitality. The results of the work – privately owned tracts of land holding planted from Dubravas EMMU forest in N and NE – 80 metres away from the forest edge and in the privately owned tracts of land during 5 years, were formed strong ( more than 5000 thous. trees/ha) forest natural regeneration located unevently. Their species composition is determined by stand structure forest edge. The natural regeneration quality depends on soil conditions.The total amount of Nd saplings by site are 24% higher than in Nc. Naturally regenerattion of forest, in the depth stand and owned tracts of land are not the same... [to full text]