In Mediterranean organic vineyards, particularly in Spain, soil tillage is the most common strategy to control weeds (MAPA, 2024). However, some authors point out that fuel consumption in vineyards results in more than twice the carbon footprint of pesticide or fertilizer use (Jradi et al., 2018). Additionally, this approach can be expensive and sometimes complex, especially when weeds proliferate under the vine row, where they compete most intensely with the vines. Furthermore, depending on the architecture, vegetative structure and proliferation of certain weeds, continuous interventions are required for effective control. In contrast, in other wine-growing regions and production systems, weed management is often based on chemical control without soil disturbance, which presents different trade-offs in terms of soil quality, biodiversity, and long-term sustainability (Griesser et al., 2022).

Annual weeds are typically effectively controlled through tillage, although their staggered germination and emergence over several weeks or even months require repeated interventions (Davis et al., 2018). Vineyards host annual weed species with varying germination periods. In the study region, winter species, such as Stellaria media, Galium aparine, Hordeum murinum, Veronica hederifolia, and Polygonum aviculare, germinate between November and January and complete their cycle by May–June (Grundy et al., 2003). In contrast, summer species like Chenopodium album, Amaranthus retroflexus, Setaria verticillata, and Echinochloa crus-galli germinate in April and May, completing their cycle by late summer or autumn (Jursík et al., 2010). Additionally, there are perennial weed species that maintain active underground organs (roots, rhizomes, or stolons) during the winter, allowing regeneration, such as Convolvulus arvensis, Cynodon dactylon, and Cirsium arvense, especially from April onwards (Davis et al., 2018; Valencia-Gredilla et al., 2020). This diversity in weed life forms, seasonality, and high adaptability to vineyard soil management ensures their presence throughout the growing season.

The frequent mechanical interventions mentioned above are the primary weed control strategy in most Mediterranean dryland vineyards, particularly in organic vineyards. In addition to these interventions, plant protection in organic systems relies almost exclusively on preventive phytosanitary treatments (e.g., sulfur and copper) due to the limited availability of curative products. This constraint often requires repeated applications closely linked to weather conditions and disease pressure, increasing the number of machinery passes throughout the season. Collectively, these practices contribute to increase CO₂ emissions and fuel consumption. Furthermore, repeated soil tillage can lead to the loss of soil structure and biodiversity, compromising the sustainability of production (Visconti et al., 2024). Continuous machinery traffic can also cause soil compaction, increasing the risk of root asphyxiation in vineyards, runoff and soil erosion (Batey, 2009; Biddoccu et al., 2016; Keller et al., 2017).

Vineyard weed management distinguishes between two soil management areas: the inter-row space (alleyway) and the area beneath the vine row (or cordon). The implementation of a vegetative cover (cover crop) in the alleyways and an organic mulch under the cordons presents an interesting alternative to reduce the need for mechanical interventions in both areas. A vineyard cover crop is a soil maintenance technique that involves keeping the vineyard soil surface covered with vegetation, either through spontaneous flora or by sowing specific cover crops for this purpose (EVENA, 2012). The implementation of a cover crop offers multiple agronomic and environmental benefits, such as increasing soil organic matter, biomass, and microbial activity, as well as enhancing soil structure, water retention capacity and fertility. Additionally, cover crops reduce runoff and erosion (Gómez et al., 2011; Guzman et al., 2019), facilitate machinery movement even on rainy days (Capello et al., 2019), and exert competitive pressure on weed emergence (Baumgartner et al., 2008). Both, spontaneous and sown cover crops can provide desired soil improvements such as increased fertility, organic carbon, and macroaggregate stability; and in the case of the spontaneous cover, greater biomass can be achieved depending on its composition and establishment (Guzman et al., 2019). Organic mulches, on the other hand, have a weed-suppressing effect due to both their physical properties (light and temperature interception) and potential allelopathic compound release, reducing the emergence of certain weed species by up to 80% (Dhima et al., 2006; Cabrera-Pérez et al., 2022). In vineyards, mulching has also been observed to improve various soil quality indicators, such as moisture and structure (Zribi et al., 2011; DeVetter et al., 2015).

In this context, the implementation of strategies aimed at reducing mechanical interventions in vineyards should be aligned with improved sustainability, thereby supporting decision-making consistent with Spanish CAP subsidies that promote the establishment of cover crops. However, in rainfed Mediterranean vineyards, this decision remains particularly challenging, as trade-off between productivity and sustainability still needs to be carefully weighed and can only be clarified through experimental evidence. To reduce mechanical interventions for weed control in the vineyards of Familia Torres, the implementation of cover crops in the alleyway, as well as organic mulches beneath the vine row, is being considered. Previous studies have shown promising results. Cover crops based on grasses (Bromus diandrus, Hordeum vulgare, Lolium multiflorum) have been effective in vineyards in Rioja, Navarra, and Lleida (Ibáñez, 2015; EVENA, 2012; Valencia-Gredilla et al., 2020; Recasens et al., 2023). Similarly, chopped vine pruning mulches applied beneath the under-vine area have proven effective in vineyards in València (Buesa et al., 2021). The success of cover crop establishment and persistence depends as much on regional rainfall patterns as on irrigation availability. Regarding organic mulching, material consistency and durability are key factors. Previous studies (Cabrera-Pérez et al., 2022) have shown that a 10 cm thick and 40 cm wide pine chip mulch under the vine row is highly effective in suppressing weed emergence while maintaining a high soil cover (>90%) and a persistence of at least three years. The use of organic mulches in the under-vine area could facilitate weed suppression by providing a competitive yet low-impact cover that stabilizes the soil surface and reduces weed emergence. Additionally, the persistence of organic mulches could reduce the need for mechanical interventions. Meanwhile, the establishment of cover crops in the alleyways could compete with existing weeds, particularly winter-spring species, and after mowing or rolling, create a soil cover that could help limit the runoff and erosion and prevent the growth of some summer annual weeds (Cabrera-Pérez et al., 2023).

In addition, Cabrera-Pérez et al. (2022) used the principle of light detection and ranging (LiDAR) to assess the effect of weeds, cover crops and organic mulches on vine development. The authors compared and validated the results of manual traditional canopy development measurements with those obtained with a mobile terrestrial laser scanner (MTLS) based on LiDAR. The measurements based on LiDAR proved consistent and reliable. LiDAR-based technology was used in agriculture for the first time by Walklate (1989) and Wangler et al. (1993). Other articles focus on the methodology to produce and improve the accuracy of point clouds (Rosell Polo et al., 2009; Moreno et al., 2020; Lavaquiol-Colell et al., 2025) and extract parameters from vine canopies (Siebers et al., 2018; Del-Moral-Martínez et al., 2020; Chedid et al., 2023 and Vélez et al., 2023). LiDAR-derived data have been used alone to detect weeds in annual crops (Andújar et al., 2013; Shahbazi et al., 2021) and fused with RGB imagery to quantify weed infestation (Ban et al., 2024; Romero and Heenkenda, 2024);. However, to our knowledge, no studies, beside Cabrera-Pérez et al. (2023), have used LiDAR to assess the effect of weeds, cover crops and organic mulches on vine development.

The objective of the study was to assess the effects of two different soil management strategies, namely cover crops in the alleyways and organic mulch in the under-vine area, with the aim of reducing tillage. In the alleyway, the cover crop installation capacity of H. vulgare and L. multiflorum and their competition against weeds was assessed, as well as their effects on vine vigor compared to traditional alleyway tillage. In the under-vine area, the effect of an organic mulch (chopped pine wood) on vine vegetative growth (through direct and indirect measures), yield, and weed control, was compared to that of tilled control.

Despite the initial reluctance of some winegrowers to introduce vegetation into vineyards, cover crops have increasingly been adopted due to their agronomic and environmental benefits and the economic incentives growers can receive (Garcia et al., 2018). In this study, the use of winter annual grasses (H. vulgare and L. multiflorum) in the alleyways resulted in effective suppression of spontaneous weed flora. Weed coverage remained below 10% in all cases and was particularly low in L. multiflorum plots, where values did not exceed 2.7% during the critical spring period. These results are consistent with previous studies conducted in Mediterranean vineyards reporting a strong weed-suppressive capacity of grass cover crops (Ibáñez, 2015; Baumgartner et al., 2008; Valencia-Gredilla et al., 2020).

However, a clear competitive effect on vine vigor was observed, particularly under the extremely dry conditions prevailing during the experimental period. Vines flanked by tilled alleyways showed consistently higher cross-sectional area, pruning weight, and yield than those flanked by a cover crop. These differences were statistically significant for several parameters, especially in 2022, a year characterized by a severe drought.

Although two different grass species were used as alleyway cover crops (H. vulgare and L. multiflorum), their effects were considered equivalent for the purpose of the statistical analysis due to their morphological and functional similarity. Both species belong to the same functional group of annual winter grasses and exhibit comparable growth cycles. Previous reviews and comparative studies indicate that the agronomic effects of cover crops on vine performance are primarily driven by their functional type (grass vs. legume vs. mixture) rather than by species identity within the same group. Experiments comparing several grass species have reported consistent trends in soil coverage and erosion reduction, weed suppression, water competition, and soil mineral composition changes with differences among species being minor compared with those among functional groups (e.g., Hordeum vulgare, Lolium multiflorum, and Avena sativa showing similar outcomes under Mediterranean conditions) (Abad et al., 2021; Varga et al., 2012; Gontier et al., 2014; Messiga et al., 2015). Therefore, grouping both covers as a single “grass cover crop” category is justified from a functional perspective. Nonetheless, the small differences observed in the LiDAR readings between tillage–Hordeum and tillage–Lolium combinations in 2021 suggest that species × year interactions, driven by rainfall variability, may modulate the intensity of competitive effects. This observation is consistent with previous research showing that the agronomic response to annual cover crops in vineyard alleyways can range from positive to negative depending on climate, soil properties, management intensity, and production system (Dzvene et al., 2023), highlighting the delicate balance between weed control, soil improvement, and competition with the crop in water-limited environments (Ehrenfeld et al., 2005; Abad et al., 2021).

Several authors have reported that while grass cover crops improve water infiltration in winter, grass transpiration in spring leads to water stress values similar to those of the grapevines managed under bare soil (Celette et al., 2005; Celette and Gary, 2013; Cunial et al., 2025). The results presented in this paper confirm that winter cover crops can effectively contribute to weed suppression, but they may also compete with vines for soil water during spring—an effect that is exacerbated under rainfed conditions and particularly relevant in Mediterranean vineyards without supplemental irrigation, as previously demonstrated by Muscas et al. (2017). In addition, based on evidence from the literature, winter cover crops have been reported to potentially improve soil structure, enhance biodiversity, and reduce the carbon footprint of vineyard management systems (Dong et al., 2025), although these aspects were not directly assessed in the present study.

Under average rainfall conditions, however, winter annual cover crops such as those evaluated here would be expected to show faster establishment, higher soil cover and greater biomass production, thereby enhancing their potential benefits in terms of soil protection and weed suppression (Celette et al., 2008; Abad et al., 2021). Previous studies conducted under less restrictive water availability conditions have reported more stable cover crop performance, while the impact on vine water status seemed to depend on cover crop species, percentage of soil covered, and the timing and duration of their development throughout the season, among others (Celette and Gary, 2013; Muscas et al., 2017).

In the context of climate change, characterized by increased rainfall variability and more frequent drought events in Mediterranean regions (IPCC, 2021), the performance of cover crops will likely depend on species selection and adaptive management strategies. Winter annual species with short growing cycles and early senescence may remain suitable options, as they allow soil protection during the rainy period while minimizing water competition during the critical summer months (Abad et al., 2021). Therefore, although cover crop establishment may be increasingly challenged under future climatic scenarios, their strategic use during wetter years or seasons could still contribute positively to the resilience and sustainability of Mediterranean rainfed viticulture.

Regarding organic mulching, pine wood chips proved to be a promising alternative to mechanical under-vine in-row tillage. Weed coverage in mulched plots remained low across both years, with the few escapes mainly consisting of perennial species capable of vegetative propagation. This is consistent with previous studies showing the effectiveness of mulches in creating a physical barrier to light and limiting weed emergence (Teasdale and Mohler, 2000; Cabrera-Pérez et al., 2022). The low weed cover values observed under the tillage treatment were largely attributable to the repeated use of mechanical cultivation (both in the cover crop and mulch trials). While these operations were effective in suppressing weed emergence, they required a high number of interventions throughout the growing season, highlighting the greater management intensity associated with this practice.

Moreover, vine vigor under the pine chip mulch treatment was generally comparable to or slightly greater than that observed under traditional tillage, particularly in terms of exposed leaf area and cluster number. Although not always statistically significant, these consistent trends indicate that organic mulching does not constrain vine growth and may even enhance it under Mediterranean conditions. Similar responses have been reported in vineyards managed with woody mulches, where improved vegetative development and yield were associated with enhanced soil water availability and reduced competition from weeds (DeVetter et al., 2015; Zribi et al., 2011; Fraga and Santos, 2018).

The positive response observed under the pine chip mulch can be explained by several complementary mechanisms. First, organic mulches effectively reduce soil evaporation and buffer extreme soil temperatures, leading to improved vine water status during critical phenological stages (Buesa et al., 2021; Cabrera-Pérez et al., 2023). In addition, the high persistence and thickness of pine-based mulches limit weed emergence and growth, thereby minimizing belowground competition for water and nutrients compared with tilled or vegetated soils (Cabrera-Pérez et al., 2022). Furthermore, organic mulches do not actively transpire, which is particularly advantageous under water-limited conditions. As highlighted by Cabrera-Pérez et al. (2023), pine wood mulches can sustain vine vegetative growth and yield without inducing competition, supporting their suitability as a climate-adaptive soil management strategy.

The use of mobile terrestrial laser scanning based on LiDAR provided a high-resolution and objective assessment of canopy architecture, allowing the detection of subtle differences in vegetative growth among soil management treatments. The consistent gradient in canopy development observed in the cover crop experiment (tillage > mixed > cover crop) supports the sensitivity of LiDAR-derived canopy cross-sectional area (CSA) metrics to vineyard vigor and their strong relationship with physiological parameters such as leaf area, pruning weight, and yield. Recent research confirms the value of LiDAR and UAV-based laser scanning for reconstructing vine rows and estimating canopy traits with high spatial detail (Chedid et al., 2023; Escolà et al., 2023; Vélez et al., 2023). In particular, mobile terrestrial laser scanners provide accurate three-dimensional characterization of trellised canopies, enabling detection of lateral asymmetries between alternating rows, as in the mixed treatments of this study. These results are consistent with previous findings in Mediterranean vineyards, such as those reported by Cabrera-Pérez et al. (2023), where LiDAR-derived measurements of canopy structure and vigor correlate with vine water status and yield. In that study, under-vine mulches maintained vine vigor, whereas alleyway cover crops induced measurable water competition detectable through LiDAR-based canopy metrics. Overall, integrating LiDAR measurements into vineyard soil management trials enhances the capacity to link structural canopy responses with physiological and agronomic performance.

The overall results suggest that partial implementation of a cover crop (e.g. alternating cover and tillage rows) may help mitigate competitive effects while still delivering some of the ecological benefits of cover cropping. Regarding the under-vine management, vines in mulched rows exhibited significantly larger canopy cross-sections than those managed with under-vine tillage. This reinforces the potential of pine chip mulches as both a weed control and vigor-maintaining strategy in dryland, so combining both strategies (cover crops and mulches) may be an interesting management in rainfed vineyards.

The use of winter annual cover crops (Hordeum vulgare and Lolium multiflorum) in vineyard alleyways effectively suppressed weed emergence, maintaining weed cover levels below 10% for most of the season. Under rainfed Mediterranean conditions, these cover crops had a competitive effect on vine vigor, especially in dry years, reducing yield and pruning weight compared to traditional tillage-based management. LiDAR-based canopy analysis confirmed a vigor gradient: vines flanked by tilled alleyways showed the highest canopy development, followed by those rows with mixed flanks, and those flanked by cover crops on both sides. On the other hand, pine wood chips mulch applied under the vine row effectively reduced weed pressure, with results comparable to tillage, and showed high persistence (over two seasons) and no negative impact on vine vigor. Hence, in rainfed organic vineyards, organic mulching represents a reliable and sustainable alternative to mechanical under-vine tillage.