An investigative weed flora survey was conducted in parthenium-infested maize fields in West Gojjam Zone in 2019/2020. The objective was to investigate the distribution and impact of parthenium on species diversity. A survey was conducted on 90 fields using 2 m × 2 m (4 m2) quadrats (totally 270). A total of 110 weed species belonging to 27 families were identified out of these families. Asteraceae with 26 species (23.36%) and Poaceae with 18 species (16.36%) were abundant. The highest importance value (IV) was recorded by Ageratum conyzoides, Amaranthus hybridus, and Bidens pilosa, with 28.05, 19.18, and 13.16%, respectively, in no parthenium infestation level. The highest IV of 27.08, 17.71, and 16.44%, respectively, was shown by Ageratum conyzoides, Bidens pilosa, and Galinsoga parviflora with 27.08, 17.71, and 16.44%, respectively, in very low parthenium infestation level. Ageratum conyzoides (29.38%), Bidens pilosa (24.10%), and Parthenium hysterophorus (22.68%) had the highest IV in low parthenium infestation level. Parthenium hysterophorus (91.32%), Ageratum conyzoides (17.19%), and Echinochloa colona (16.34%) had high IV in moderate parthenium infestation level. It is concluded that Ageratum conyzoides, Bidens pilosa, Echinochloa colona, and Galinsoga parviflora were competitive over parthenium based on importance value, and this indicates to suggest parthenium as a biological management option.

A field experiment was conducted to elucidate the effect of integrated management on parthenium and yield components and yield of maize. The experiment was laid in a randomized complete block design with 14 treatments with a factorial arrangement. The highest parthenium density (87.80 m−2) and dry biomass (764.61 g/m2) were recorded by weedy check while the lowest was in weed‐free check (0.00 m−2 and 0.00 g/m2), respectively. Late physiological maturity (140 days) was observed in 2,4‐D+Straw mulching and weed‐free check at Upper Bir and early maturity (133.00 days) were in weedy check at Lower Bir. 2,4‐D+Twice hand hoeing and Butrazine + Straw mulching with 308.23 cm showed higher plant height at Lower Bir and least was in weedy check (265.96 cm) at Upper Bir. The highest numbers of kernels per ear, 1,000 kernels weight and grain yield (714.75, 438.33 g, and 11.40 tha−1) were recorded on weed‐free check at Lower Bir and the lowest was on weedy control (418.00, 438.33 g, and 5.29 tha−1) at Upper Bir, respectively. The maximum dry biomass of maize was recorded for Butrazine + Straw mulching (13.51 tha−1) at Lower Bir and the minimum was recorded for weedy control (7.68 tha−1) at Upper Bir. Weed‐free control (93.42%) and weedy control (68.95%) had the highest and lowest harvest index at Upper Bir, respectively. Therefore, using 2,4‐D with straw mulching could provide good control of parthenium, economical, and ultimately better yielded.

Background: The reserve of viable weed seeds present on the soil surface and scattered throughout the soil profile. Objective: A glasshouse study was conducted to determine the special abundance of soil seed bank flora in parthenium invaded maize fields in West Gojjam Zone. Methods: The soil samples were collected from 90 fields at 0-5 cm, 5-10 cm and 10-15 cm soil depth with 10 cm width. Results: A total of 121 weed species belonging to 27 families were found in the soil seed banks. The most frequent families were Poaceae (31 species), Asteraceae (21 species) and Leguminosae (9 species). The highest importance value was recorded by Parthenium hysterophorus, Ageratum conyzoides and Echinochloa colona with 19.05, 19.02 and 14.37%, respectively at 0-5 cm soil depth. The highest importance values of 20.39, 20.16 and 16.54% were registered by P. hysterophorus, A. conyzoides and Galiansago parviflora, respectively at 5-10 cm soil depth. Likewise, at 10-15 cm soil depth highest importance value was recorded by A. conyzoides, P. hysterophorus and E. colona with 19.12, 17.30 and 116.13%, respectively. The Shannon diversity index at 0-5, 5-10 and 10-15 cm soil depth were 4. 46, 4.41 and 4.17, respectively. High similarity (68.10%) was observed between 0-5 and 5-10 and followed by 5-10 and 10-15 cm (60.19%) and 0-5 and 10-15 cm (55.39%). Conclusions: These results could help to predict infestation potential and could lead to improved weed management strategies in maize growing areas in the study area.