The research was carried out to determine the effects of soil pH (or liming) and nitrogen (N) fertilization on the common mugwort (Artemisia vulgaris L.) and cup plant (Silphium perfoliatium L.) dry mass (DM) yield, calorific value and mechanical properties. Field experiments were set up in 2008 in Western Lithuania on a naturally acid (pH 4.2-4.4) moraine loam. According to the averaged data of four experimental years, the highest DM yield 4100 kg ha -1 of common mugwort was established in 2009, which significantly decreased in the subsequent years. And, conversely, the highest cup plant DM yield 17980 kg ha -1 was obtained in 2011. An increase in soil pH from 4.2-4.4 up to 5.6-5.7, resulting from 6.0 t ha -1 CaCO 3 application, increased cup plant DM yield by 27.4%. Fertilization with 120 kg ha -1 N significantly increased common mugwort and cup plant DM yield by 34.5% and 26.7% respectively, compared with the treatment without N fertilization. We also studied the chopping quality of common mugwort and cup plant and chaff fractional composition using sieves with different mesh sizes. The chaff of cup plant was finer and more even, and thus more suitable for use for energy purposes. Plant milling quality showed cup plant particles to be smaller and more even too, and thus better suited for pressing and combustion. The highest calorific value of common mugwort (17.97 MJ kg -1 ) was obtained in 2010 and that of cup plant (17.48 MJ kg -1 ) in 2012. The calorific values of common mugwort and cup plant were influenced most by the year of cultivation and 120 kg ha -1 N application.

Wide span tractors/vehicles have good prospects as the mechanisation means for controlled traffic farming. The efficiency of the practical application of wide span tractors (vehicles) depends on the availability of the substantiated scientific basis or the theoretical basis for the research into their key properties, including among other factors the smoothness of movement. The aim of the research is to improve the smoothness of movement of wide span tractors (vehicles) by substantiating their configuration, design-and-process and other parameters as well as the properties of the longitudinal profile of the agricultural background irregularities in the ruts of the laid-down process track. The smoothness of movement of the wide span tractor (vehicle) as a dynamic system travelling in the ruts of the permanent process track substantially depends on the structure of the latter's longitudinal profile, the stiffness of tyres on the supporting wheels, while the dynamics of the vertical oscillations of the process section depends on its operating weight.

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In order to increase the cost-effectiveness of blueberry (Vaccinium) cultivation in blueberry plantations, all of its technological operations should be automatized. It is reasonable to start the automation of blueberry cultivation from the technological operation of fertilising the blueberries as the main purpose of this operation is to dose a prescribed amount of fertiliser under the plant's crown. When a new blueberry plantation is established on depleted peat milling fields, then the plants are set at pre-determined steps into parallel rows. Fertilisation of the plants in the first years of growth must be performed individually, i.e. each plant is fertilised separately. This is called precision fertilisation. In order to design the technological devices for blueberry cultivation, i ncluding the fertiliser robot, it is important to know the location of plants on the field or, more precisely, their position in the row. The goal of this study is to determine the position of blueberry plants in the plantation. In order to meet the goal, measurements were performed in the blueberry plantation and the position of plants in randomly chosen row was measured. It became clear from the study that plants are not positioned regularly at equal intervals in a straight line; therefore, the fertiliser robot to be designed must include t he functions of plant identification and control of fertiliser jet to ensure individual or precision fertilisation of plants.

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