The finger weeder cultivator for intra‐row mechanical weed control: Effects of uprooting force on selected weed species.

Mechanical weed control tools are commonly used in the production of many vegetable and field crops. This study aimed to determine the impact of weed species and growth stage on the finger weeder performances and to reveal the relation between root morphology, uprooting force and control efficacy. A one‐month field experiment with two model species, Triticum aestivum L. (grass) and Sinapis alba L. (broadleaf), showed that finger weeder control efficacy was affected by species and growth stage: Finger‐weeder application during the first two growth stages (cotyledon and second leaf) was more effective for S. alba than for T. aestivum (p < 0.0001), but at fourth‐leaf stage values for control efficacy were not significantly different (p = 0.134). In an experiment conducted in pots it was found that, at all three growth stages, the uprooting force required for S. alba was significantly lower than that for T. aestivum (p < 0.0001), indicating a lower anchoring force of the former. Determination of root‐morphology parameters revealed significantly higher root parameters, like length, in T. aestivum than in S. alba at the early developmental stages. Correlation of the control efficacy and uprooting force revealed a 2.5‐N threshold value for effective weed control. Additionally, net‐house and field experiments showed significant differences in the uprooting forces required for 10 different Mediterranean grasses versus broadleaves weed species at all developmental stages. To translate these findings into applicative recommendations, future research should characterize the relationship between the operational factors of this tool and the required uprooting force. [ABSTRACT FROM AUTHOR]