In the Amhara region, Ethiopia, sorghum production took 655,671 hectares of land, of which North Gondar zone accounts for one-third of it, 204, 686 ha. But its productivity is low, around 1.9 tons per hectare.  Sorghum production has so many constraints, insect pest, disease, and weed infestation are the most known among them. Farmers in the Northwestern Ethiopia, Gumara-maksegnit watershed have no weeding habit of their sorghum at the right time and frequency because they believe that weed-free crops at the early stage of the crop will be infested with stalk borer damage and after at the beginning of September they start to weed their land and used the weed as a feed for their animal. Therefore the objective of this study was to determine the weeding frequency of sorghum in Gumara-maksegnit watershed, North Western Ethiopia in order to increase its productivity. The experiment was conducted in the Gumara- maksegnit watershed for two cropping seasons (2014-2015) in the main season at three sites. The experimental design was arranged in a randomized complete block design with three replications. Treatments like weed-free, unweeded, and farmers practice treatments, hand weeding once, two times hand weeding, three times hand weeding, and Shelshalo were studied. According to the combined analysis of variance of the two-year data showed that weed-free treatments gave the highest yield (3314 kg/ha) followed by two times and three times hand weeding. However, there was no significant difference between weed-free and two times hand weeding. Therefore, two times hand weeding is recommended for Gondar Zuria and similar agroecological areas.

Weeds compete with crops grown for resource limits such as water, nutrients, and light. Weed infestation is one of the major factors limiting sesame production, as its seedlings grow slowly during the first few weeks making it a weak competitor at earlier crop growth stages. Weed induced sesame yield reductions of up to 65 percent, and a need for a crucial weed-free duration of up to 50 days following planting. Weed surveys are useful for determining the occurrence and relative importance of weed species in crop production systems. Weed survey on a farm basis is needed to establish efficient weed management and decision making mechanisms and to evaluate weed control measures. Therefore this survey was conducted to assess qualitative and quantitative weed species in sesame growing areas of west Gondar, Ethiopia. Weed survey was conducted in 2012 at Metema and 2013 main cropping season at Metema, Tach Armachiho, and Mirab Armachiho district. data on weed species type and count were taken along the diagonal with 50cm x 50cm quadrate at a 15-meter interval at three points. Visual identification, manuals, photographs, leaflets, and books were used for identifying weed species. They conducted interviews with farmers, development agents, and district experts working in the region. Weed species compositions were analyzed by frequency, abundance, dominance, and similarity index. In the districts, 31common weed species or groups of species from 17 families were recorded. Ipomea cordofana Br., Grass spp’, Commelina benghalensis L. Andropogon abyssinicus (Fresen) R.Br., Boerhaavia erecta L., Corchorus olitorius L.kudra, Corchorus trilocularis L., Leucas martinicensis (Jacq) ait.f. and Ipomea triloba are the most prevalent, abundant, and important weeds in sesame fields in north Gondar. As to this on-farm and practical training on identification and demonstration management options should be given on the low land of north Gondar farmers.