Field trials were conducted over the period 1998–2001 at the Voke Branch of the Lithuanian Institute of Agriculture on a sandy loam Haplic Luvisol (LVh). Pea’s precrop was winter rye. Crop residues were returned to the soil; straw was chopped at harvest. The aim of the investigation was to determine the effect of stubble breaking, ploughing at different depths on the weediness of cultivated crop, as well as on the crop yield.

Most couch-grass (Elytrigia repens (L.) Nevski) infested were unbroken-stubble and shallow-ploughed plots. It caused a yield reduction by 11–20%. The lowest numbers of weeds were counted and the highest pea’s yield was obtained on broken stubble, 0.22–0.25 m depth ploughed.