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Glyphosate is one of the most widely used herbicides, but is still in the spotlight due to its controversial impact on the environment and human health. The main purpose of this study was to explore the effects of different glyphosate usages on harvested grain/seed contamination. Two field experiments of different glyphosate usage were carried out in Central Lithuania during 2015–2021. The first experiment was a pre-harvest application, with two timings, the first according to the label (14–10 days), and the other applied 4–2 days before harvest (off-label), performed in winter wheat and spring barley in 2015 and 2016. The second experiment consisted of glyphosate applications at label rate (1.44 kg ha−1) and double dose rate (2.88 kg ha−1) at two application timings (pre-emergence of crop and at pre-harvest), conducted in spring wheat and spring oilseed rape in 2019–2021. The results suggest that pre-emergence application at both dose rates did not affect the harvested spring wheat grain or spring oilseed rape seeds—no residues were found. The use of glyphosate at pre-harvest, despite the dosage and application timing, led to glyphosate’s, as well as its metabolite, aminomethosphonic acid’s, occurrence in grain/seeds, but the amounts did not reach the maximum residue levels according to Regulation (EC) No. 293/2013. The grain storage test showed that glyphosate residues remain in grain/seeds at steady concentrations for longer than one year. A one year study of glyphosate distribution within main and secondary products showed that glyphosate residues were mainly concentrated in wheat bran and oilseed rape meal, while no residues found in cold-pressed oil and wheat white flour, when glyphosate used at pre-harvest at the label rate.

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Cover cropping is a successful soil conservation technique, but it has limitations and must be recognised as part of a well-planned integrated farming system. Environmental conditions, soil type, crop, and tillage method are factors that should be taken into consideration before building cover crops into the farming system. The aim of this study was to explore the effect of cover crop management under different tillage practices on the spring barley (Hordeum vulgare L.) root growth and the interaction with soil hydrophysical properties. The experiment was conducted in Central Lithuania in Endocalcari-Epihypogleyic Cambisol, a loam texture soil. The split-plot experiment was conducted: tillage -ploughing, harrowing, and direct drilling, as subplot, and cover crop -with cover crop and without cover crop, as main plot. A significantly higher total porosity and microporosity of topsoil was identified in ploughing, and direct drilling resulted in a significantly higher soil bulk density, lower total porosity and microporosity, but did not change meso-and microporosity. The establishment of cover crop has resulted in a significantly higher soil microporosity and lower mesoporosity as well as tended to decrease the soil bulk density and to increase the root diameter and volume for all tillage treatments in a 5-20 cm layer. The root length and root volume of spring barley positively correlated with the soil total porosity, whereas the correlation of root parameters with the bulk density was negative. The influence of the cover crop and tillage interaction was significant for the soil bulk density and root diameter.