Testing the Efficacy of Pelargonic Acid and Acetic Acid for Weed Control in an Apple Orchard

Alexandra Maria Bardoș Marțiș, Mihaela Olaru, Ailin Moloșag, Mihaela-Cecilia Dogaru,
Maria-Marinela Dragnea, Vlăduț Loredan Holt 

Research and Development Station for Fruit Tree Growing Băneasa

Keywords: pelargonic acid, acetic acid, apple orchards, natural herbicides.

Abstract: This project evaluates the effectiveness of two natural herbicides, one containing pelargonic acid and the other acetic acid, on apple yield and weed infestation under field conditions at the Moara Domnească Experimental Base of the Research and Development Station for Fruit Growth Băneasa during the 2025 growing season.
The experimental setup included five treatments: mechanical control, natural herbicides with pelargonic acid and acetic acid, a conventional herbicide, and an untreated control. These treatments were arranged in a randomised complete block design with three replicates. Each plot measured 29 m², with treatments applied between plants along the row. The dynamics were monitored through assessments carried out before treatment, at 7 days, and at 30 days after application. 66% of the weeds found in plots were dicotyledons from six botanical families. In the case of pelargonic acid, after treatment and the final assessment, the mean reduction for dicotyledons was 63%. Acetic acid herbicide, under the same conditions, reduced dicotyledon growth by 33%. Compared with the conventional herbicide, which had 100% reduction for both dicotyledons and monocotyledons.
Yield was measured at the plot level (kg/ha), and the crop's phytosanitary status and ground cover were evaluated. These results are expected to reveal the impact of implementing agroecological practices and natural herbicides as sustainable alternatives to traditional weed-control methods in apple orchards.