Effect Of Leaf Removal Research Articles

Effects of Leaf Removal on Free and Glycoconjugate Aromas of Skins and Pulps of Two Italian Red Grapevine Varieties.

Leaf removal is a cultural practice mainly aimed at improving cluster zone microclimates and impacting primary and secondary metabolites, such as volatiles. This research aimed to assess the impact of defoliation on free and glycosylated aromas of a neutral ('Nebbiolo') and a semi-aromatic ('Aleatico') red variety. Defoliation was performed at fruit set (BBCH 71) and, for 'Nebbiolo', also at berries touch (BBCH 81) phenological stages. Skins and pulps were separately analyzed by Solid Phase Extraction-Gas Chromatography/Mass Spectrometry. Results showed that the response to defoliation was variety-dependent. For 'Nebbiolo', especially when performed at the berries' touch stage, defoliation had a significant effect on the accumulation of free volatiles and glycosidic precursors. Differently, free and bound 'Aleatico' volatiles were less impacted by defoliation. Interestingly, in both grapevine varieties, defoliation significantly enhanced the accumulation of aroma precursors in grapes' skins, which is of particular relevance for red wine production and their aging potential. Moreover, results could be helpful for the management of grape quality, as defoliation is currently considered as a strategy to address climate change issues.

Effect of Leaf Removal and Insecticide Applications on Population Densities of Leafhoppers and Mites Associated with Grapevines.

In this study, we tested the effects of mechanical leaf removal, insecticide application, and their interaction on leafhoppers and phytophagous and predatory mites occurring in two vineyards over three growing seasons. Leaf removal was performed in the fruit zone using a two-head pulsed air leaf remover, while insecticides were applied with a tunnel air-assisted sprayer at the maximum dose/ha recommended on the product label. Results demonstrated the efficacy of insecticide application in reducing the population densities of leafhoppers but also their detrimental effects on predatory mites. In a number of case studies, leaf removal reduced leafhopper and predatory mite densities. In one vineyard, phytophagous mite populations increased some weeks after leaf removal and insecticide application, highlighting the need to carefully consider the potential impact of vineyard management practices on non-target arthropods in the IPM framework.

Impact of meteorological conditions, canopy shading and leaf removal on yield, must quality, and norisoprenoid compounds content in Franciacorta sparkling wine.

Climate change is a major concern in agriculture; in grapevine production, climate change can affect yield and wine quality as they depend on the complex interactions between weather, plant material, and viticultural techniques. Wine characteristics are strongly influenced by microclimate of the canopy affecting primary and secondary metabolites of the grapevine. Air temperature and water availability can influence sugar and acid concentration in grapes and relative wines, and their content of volatile compounds such as norisoprenoids. This becomes relevant in sparkling wine production where grapes are generally harvested at a relatively low pH, high acidity, and low sugar content and where the norisoprenoids significantly contributes to the final aroma of the wine. The effect of climate change on grapevine and wine, therefore, calls for the implementation of on-field adaptation strategies. Among them canopy management through leaf removal and shading have been largely investigated in the wine growing sector. The present study, conducted over 4 years (2010-2013) aims at investigating how leaf removal and artificial shading strategies affect grape maturation, must quality and the production of norisoprenoids, analyzed using an untargeted approach, in sparkling wine. Specifically, this paper investigates the effect of meteorological conditions (i.e., water availability and temperatures) and the effect of leaf removal and shading on Vitis vinifera L. cv. Chardonnay and Pinot noir, which are suitable to produce sparkling wine in the DOCG Franciacorta wine growing area (Lombardy, Italy). The effect of leaf removal and shading practices on norisoprenoids has been the focus of the study. No defoliation and artificial shading treatments play an important role in the preservation of the acidity in warm seasons and this suggests calibrating defoliation activities in relation to the meteorological trend without standardized procedures. This is particularly relevant in the case of sparkling wine, where the acidity is essential to determine wine quality. The enhanced norisoprenoid aromas obtained with a total defoliation represent a further element to direct defoliation and shading strategies. The obtained results increase knowledge about the effect of different defoliation and artificial shading applications in relation to meteorological condition supporting the management decision-making in the Franciacorta wine growing area.

Effect of leaf removal and ripening stage on the content of quercetin glycosides in Sangiovese grapes

Quercetin haze has been observed over the last few years in some aged Sangiovese wines. This problem could be due to an excess of the quercetin in the wine. Leaf removal increases the exposition of clusters to sunlight, which may enhance flavonol synthesis in the grapes. In this study, we evaluated the dynamics related to extractable flavonols in grapes grown in three usually defoliated Vitis vinifera (L.) cv. Sangiovese vineyards, whose wines showed quercetin precipitates. The particular structure of the vineyards in which the leaf removal experiments were carried out allowed the influence of vineyard, biotype and rootstock on grape flavonol contents at mid-maturation and technological maturity to be evaluated. The leaves were removed at pre-flowering (early) and at veraison (late). Leaf removal increased the content of extractable glycosidic flavonols in grapes at the two tested ripening stages. In addition, vineyard, biotype and rootstock affected the content of glycosidic flavonols and the interaction between the studied variables was significant. Even though leaf removal induced an increase in extractable quercetin glycosides which can increase the risk of quercetin haze in wine, an examination of the scientific literature on this topic showed that this risk does not depend on the absolute content of these compounds alone.

Effects of leaf removal on hexose accumulation and the expression of sugar unloading-related genes in syrah grapes

Leaf removal (LR) around the cluster zone is a common practice for regulating grape quality. The purpose of this study was to assess the effects of cluster-zone leaf removal, applied at the pea-size stage of berry development, on berry soluble sugar, organic acid and phenolic compound, sugar unloading-related gene expression of Vitis. vinifera L. Syrah. Four different severities of leaf removal were applied: no leaf removal (Control), removing 2 leaves above the cluster (LR1), removing 4 leaves above the cluster (LR2), and removing 6 leaves above the cluster (LR3). The three leaf removal treatments (LR), especially removing 4 leaves (LR2), resulted in significantly higher reducing sugar, soluble sugar (glucose, fructose and sucrose), total anthocyanin and citric acid contents as compared to the control group during ripening for both vintages. At harvest, the LR treatments increased the transcript abundance of most sugar unloading-related genes. In addition, VvHT3, VvHT5, VvSUC11, VvSUC12, VvSS and VvcwINV were positively correlated with both reducing sugar contents and soluble sugar contents. Our results suggest that removing 4 leaves above the cluster is useful for improving the quality of Syrah (Vitis vinifera L.) grapes in cool climate regions with excessive leaves. These findings provide insights into the molecular basis of the relationship between leaf removing and hexose (glucose and fructose) accumulation in the grape berries.

The Effect of Cutting and Waterlogging on Plant-Related CO2 and N2O Fluxes Associated with the Invasive N-Fixing Species Gunnera tinctoria

The overall impact that plant invasions have on greenhouse gas emissions (GHG) by plant-mediated effects and how these interact with environmental and management factors is largely unknown. To address this, we report on the effects of leaf removal and waterlogging, either singularly or in combination, on the fluxes of CO2 and N2O associated with the invasive species Gunnera tinctoria. Both the removal of leaves with and without flooding resulted in higher CO2 emissions due to reductions in photosynthesis. Whilst waterlogging alone was also associated with a reduction in photosynthesis, this was slower than the effect of leaf removal. Significant N2O emissions were associated with intact plants, which increased immediately after leaf removal, or seven days after waterlogging with or without leaf removal. We found positive correlations between CO2 and N2O emissions and petiole and rhizome areas, indicating a size-dependent effect. Our results demonstrate that intact plants of G. tinctoria are a source of N2O emissions, which is enhanced, albeit transiently, by the removal of leaves. Consequently, management interventions on invasive plant populations that involve the removal of above-ground material, or waterlogging, would not only reduce CO2 uptake, but would further compromise the ecosystem GHG balance through enhanced N2O emissions.

Effect of Leaf Removal on Quantitative and Qualitative Characteristics of Autumn Sugar Beet Cultivars in Golestan Province

در گیاهان، برگ‌ها، اصلی‌ترین محل دریافت تابش خورشیدی و تولید مواد فتوسنتزی هستند، به همین دلیل برآورد میزان کاهش عملکرد ناشی از بین رفتن برگ‌ها، نقش مهمی در مدیریت مزرعه دارد. به منظور بررسی اثر حذف اندام هوایی (برگ و دمبرگ) در مراحل مختلف رشد رویشی بر عملکرد و کیفیت ریشه چغندرقند، آزمایشی به صورت فاکتوریل در قالب طرح بلوک‌های کامل تصادفی با سه تکرار در ایستگاه تحقیقات کشاورزی و منابع طبیعی ورسن گرگان در سال زراعی 99-1398 اجرا گردید. عامل اول شامل 6 رقم تجاری چغندرقند پاییزه (5 رقم خارجی و رقم داخلی شریف) و عامل دوم شامل سرزنی در اردیبهشت‌ماه (مرحله میانی رشد)، سرزنی در خردادماه (مرحله نهایی رشد) و تیمار شاهد (عدم سرزنی) انجام شد. در پایان فصل رشد صفات کمی و کیفی ریشه اندازه‌گیری شدند. نتایج نشان داد ارقام چغندرقند در صفات درصد قند ناخالص (عیار)، قند خالص، سدیم، پتاسیم، ضریب استحصال شکر و قند ملاس اختلاف معنی‌داری از خود نشان دادند؛ ولیکن از نظر صفات نیتروژن مضره و الکالیته بین ارقام اختلاف معنی‌داری مشاهده نشد. سرزنی چغندرقند باعث کاهش درصد قند، نیتروژن و عملکرد ریشه و افزایش میزان الکالیته و پتاسیم ریشه گردید. بیشترین ضایعات عملکرد ریشه زمانی که برگ چغندرقند در مراحل میانی رشد (اردیبهشت ماه) حذف شدند به‌دست آمد، به‌طوری‌که کاهش عملکرد ریشه در سرزنی اردیبهشت‌ماه نسبت به سرزنی خردادماه بیشتر تحت تأثیر قرار گرفت. در مجموع، مرحله‌ای از رشد گیاه که حذف برگ صورت می‌گیرد و فاصله آن تا زمان برداشت بر عملکرد و خواص کیفی چغندرقند موثر می‌باشد.

Effects of Defoliation at Fruit Set on Vine Physiology and Berry Composition in Cabernet Sauvignon Grapevines.

Grapevine canopy defoliation is a fundamentally important technique for the productivity and quality of grapes. Leaf removal is a pivotal operation on high-density vines which aims to improve air circulation, light exposure, and leaf gas exchange. The effects of leaf removal (LR) on vine physiology and berry composition in Cabernet Sauvignon grapevines were studied during the 2018–2019 growing season in the Bolgheri area, Tuscany, Italy. The basal leaves were removed at fruit set at two severity levels (removal of four basal leaves of each shoot (LR4) and removal of eight basal leaves (LR8)). The two treatments were compared with the not defoliated control (CTRL). The following physiological parameters of vines were measured: leaf gas exchange, leaf water potential, chlorophyll fluorescence and indirect chlorophyll content. The results showed that defoliation increased single leaf photosynthesis. In addition, qualitative grape parameters (phenolic and technological analyses) and daytime and night-time berry temperature were studied. The results showed that leaf removal had an impact on total soluble solids (°Brix), titratable acidity, and pH. The LR8-treated grapes had higher titratable acidity, while those in the LR4 treatment had higher °Brix and extractable anthocyanin and polyphenol content. Berry weight was not significantly influenced by the timing and severity of basal defoliation. Therefore, this research aims to investigate the effects of defoliation at the fruit set on vines performance.

The effect of leaf removal on canopy microclimate, vine performance and grape phenolic composition of Merlot (Vitis vinifera L.) grapes in the continental part of Croatia

Leaf removal in the cluster zone is one of the commonly applied viticultural practices used to increase light penetration and to decrease humidity in dense foliage. A two- year study (2018/2019) was carried out on the Merlot variety grown in the vineyard on the Croatian hillside with continental climatic conditions, to study the effects of basal leaf removal on canopy microclimate, grape chemical composition and vine production. Leaf and lateral shoot removal was performed at berry set. Meteorological data were recorded together with microclimatic measurements: air temperature, UV radiation and relative humidity in the fruiting zone. Leaf removal altered microclimate by increasing the UV radiation within the cluster zone. Sugar concentration, bud fruitfulness and yield performance was not affect by the treatment, while leaf removal significantly reduced the concentration of titratable acidity in berry samples and increased the concentration of phenols, anthocyanins, flavonols and flavan-3-ols in berry skin. Leaf removal had a higher influence on the grape anthocyanin and flavonol composition in a season with the cooler berry ripening conditions. These results revealed important difference in leaf removal efficiency on phenolic composition of the grapes in different seasonal climatic conditions during ripening.

Effects of leaf removal on grape cluster architecture and control of Botrytis bunch rot in Sauvignon Blanc grapevines in Southern Brazil

Management practices, such as leaf removal, can affect grape cluster architecture and the microclimate around the cluster, which influences the development of Botrytis bunch rot disease. The timing of leaf removal among five different phenological stages was investigated as a tool for managing grape cluster architecture-related variables and for managing Botrytis bunch rot of Sauvignon Blanc grapevines. A commercial vineyard located in São Joaquim municipality, in the highland region of Santa Catarina State, Southern Brazil, was assessed in a randomized complete block design during the 2015 and 2016 growing seasons. The treatments consisted of leaf removal of four basal leaves around clusters at the phenological stages of full bloom, buckshot berries, pea-sized berries, veraison, and 15 days after veraison. At harvest, cluster architecture variables (cluster length, cluster mass, rachis mass, number of berries, berry mass, and cluster compactness index) and Botrytis bunch rot incidence and severity were assessed weekly from the first appearance of symptoms to harvest. Disease progress curves were constructed and compared to several epidemiological parameters. There was no significant effect of the removal of four basal leaves on the cluster architecture-related variables (cluster and berry masses, number of berries, and cluster compactness index); however, reduced the intensity of Botrytis bunch rot. Leaf removal carried out before veraison significantly reduced (P < 0.05) the incidence, severity, AUDIPC, and AUDSPC of Botrytis cinerea in Sauvignon Blanc when compared with those of vines without leaf removal. Early leaf removal at the phenological stages of full bloom, buckshot berries, and pea-sized berries reduced the severity of B. cinerea infection and showed in the phenological stage of full bloom the lowest values for AUDSPC of 199.26 and 171.30 in the 2015 and 2016 growing seasons, respectively. The results of this study suggest that leaf removal carried out before veraison during the phenological stages of full bloom, buckshot berries, or pea-sized berries should be recommended for Sauvignon Blanc cultivar production to reduce Botrytis bunch rot in the highland regions of Santa Catarina State, Southern Brazil.

Effect of Leaf Removal on Composition of Wine Grape Varieties Grown in Semiarid Tropical Climate of India

Removing leaves from cluster zone is one of the management practices followed to improve fruit composition in temperate wine grape growing countries. However, knowledge on canopy management practices to improve fruit and juice composition for quality wine making is still lacking in semiarid tropical regions of India. Due to ample sunlight availability during fruit growth in semiarid tropics, it is unclear whether the leaves have to be removed from cluster zone. In case the leaves have to be removed, the direction from which it has to be done is also important. Hence, this study was conducted to see the effect of leaf removal from two sides of canopy on fruit composition in two wine grape varieties. In Cabernet Sauvignon vines leaf removal from both east and west side of the canopyimproved fruit quality in terms of reduced pH, potassium, malic acid and increased phenolics. Nevertheless, removing leaves from eastern side was found to be better than western side, because clusters are exposed toexcess sunlight. However, in Sauvignon Blanc, leaf removal from east side improved most of the desirable fruit composition parameters, while leaf removal from west side reduced the fruit quality in terms of sugars, acids, pH, total phenols etc.

Effect of Leaf Removal on Composition of Wine Grape Varieties Grown in Semiarid Tropical Climate of India

Removing leaves from cluster zone is one of the management practices followed to improve fruit composition in temperate wine grape growing countries. However, knowledge on canopy management practices to improve fruit and juice composition for quality wine making is still lacking in semiarid tropical regions of India. Due to ample sunlight availability during fruit growth in semiarid tropics, it is unclear whether the leaves have to be removed from cluster zone. In case the leaves have to be removed, the direction from which it has to be done is also important. Hence, this study was conducted to see the effect of leaf removal from two sides of canopy on fruit composition in two wine grape varieties. In Cabernet Sauvignon vines leaf removal from both east and west side of the canopyimproved fruit quality in terms of reduced pH, potassium, malic acid and increased phenolics. Nevertheless, removing leaves from eastern side was found to be better than western side, because clusters are exposed toexcess sunlight. However, in Sauvignon Blanc, leaf removal from east side improved most of the desirable fruit composition parameters, while leaf removal from west side reduced the fruit quality in terms of sugars, acids, pH, total phenols etc.

Effects of leaf removal on aromatic precursor dynamics during maturation of Ribolla Gialla grapes (Vitis viniferaL.)

Leaf removal is a viticultural practice applied in order to improve fruit-zone microclimate and berry quality. The aim of this trial was to evaluate the effect of post-flowering leaf removal on maturation and biosynthesis of terpenes and and C13-norisoprenoids in Ribolla Gialla grapes. In the seasons 2015 and 2016, basic maturation parameters were nearly unaffected by leaf removal. Contrarily, in the second season, 2016, one week before harvest, the concentration of several aroma compounds was significantly improved by leaf removal. In conclusion, the trial here showed that leaf removal improves the concentration of aroma compounds in the grapes, but the selection of the date of harvest is more crucial in order to maintain them during vinification.

Leaf removal at veraison stage differentially affects qualitative attributes and bioactive composition of fresh and dehydrated grapes of two indigenous Cypriot cultivars

The effect of leaf removal on postharvest performance of dehydrated grapes has been poorly analyzed. The aim of this study was to evaluate the effect of leaf removal at veraison stage on the metabolites of fresh and dehydrated grapes of two indigenous Cypriot cultivars ('Mavro' and 'Xynisteri'), which are destined for the production of 'Commandaria', a protected designation of origin (PDO) premium sweet wine. Leaf removal led to a reduction of soluble solids, titratable acidity, aroma potential and most of the phenolic groups in the musts of both cultivars. Dehydration led to a significant increase in all of these parameters in both cultivars, being more pronounced in cv. 'Mavro'. Interestingly, leaf removal indicated differential response in the dehydrated product of the cultivars examined; liquid chromatography (LC-DAD-qTOF-MS) data showed a significant decrease in phenolic compounds in 'Xynisteri' must (from 66.73 to 44.15 mg L-1 ), while 'Mavro' must registered similar values of phenolic compounds (from 94.78 to 96.72 mg L-1 ), but with a different distribution among phenolic groups. Intriguingly, flavonols and flavan-3-ols that present significant health-promoting properties showed higher concentrations in the must from dehydrated 'Mavro' grapes that were subjected to preharvest leaf removal. Leaf removal at veraison stage followed by sun drying differentially affected the chemical composition of the examined cultivars. This preharvest application followed by postharvest dehydration was beneficial for cv. 'Mavro', while this was not the case for cv. 'Xynisteri'. The effects of leaf removal in other developmental stages (i.e. pre/post bloom stage) need to be dissected with the ultimate goal of providing an end product with high bioactive content. © 2018 Society of Chemical Industry.

Effects of leaf removal and cluster thinning on berry quality of Vitis vinifera cultivars in the region of Weibei Dryland in China

Leaf removal and cluster thinning were carried out prior to veraison to evaluate the effects on berry quality of two Vitis vinifera cultivars (Cabernet Sauvignon and Ugni Blanc) in the Weibei Dryland of China in 2013 and 2014, and comprehensive analysis of the chemical and volatile composition in berries was performed. The results showed that content of reducing sugar in both varieties was not affected while total acid was generally decreased by leaf removal and cluster thinning. The pH of berry juice was correspondingly higher in most treatment groups. Meanwhile, promoting effects on accumulation of total phenols, tannin in both varieties and total anthocyanins in Cabernet Sauvignon were found. As for monomeric anthocyanins, percentage of malvidin and its derivatives was decreased by leaf removal and cluster thinning. Besides, cinnamylated anthocyanins decreased with the intensity of cluster thinning. The accumulation of non-anthocyanin phenolics was similarly affected in the two varieties. Notably, cluster thinning was more effective on enhancing the phenolics content than leaf removal. The combination of middle level of leaf removal and cluster thinning was the most favor to the accumulation of phenolic acids. Furthermore, cluster thinning could also significantly enhance the synthesis of flavanols and stilbenes. Lastly, content and variety of aroma compounds in both grape varieties were also significantly affected by the treatments. The results provided a theoretical basis for a combination of leaf removal and cluster thinning to improve quality of grapes and wines.

Effect of leaf removal on grape and wine composition in ‘Merlot’

The adaptation to climate change requires the adjustments of viticultural practices, particularly changing the fruit to leaf area ratio which could be an effective option to maintain and enhance fruit and wine quality. Fruiting capacity and berry composition of grapevine are dependent on canopy area, with grapevine carbohydrate reserves affected by the crop load. 'Merlot' grapevines grown in the experimental vineyard of the NWGIC (South Eastern Australia) received treatments that altered the leaf area/fruit ratio. These received severe summer pruning (SSP), upper (ULR) and lower leaf removal (LLR) implemented at pea size during two growing seasons. Generally, all treatments lowered total soluble sugars, but the total sugar yield was not altered, also the total anthocyanins and phenolics of the berries did not differ at harvest. The titratable acidity and alcohol concentration of the wine was influenced by the change of the canopy size as were sensory attributes. Particularly, wines made from grapes of the SSP treatment were different in most attributes compared to wines that were made from grapes of untreated vines. The overall response of partial defoliation and severe summer pruning conducted prior to veraison suggests that it can be used as a management practise to alter berry ripening speed and grape composition, consequentially influencing wine attributes. However, depending on position, intensity and time the impact of such treatments on carbohydrate reserves in the perennial structure may have long-term implications.

Effects of leaf removal and topping on ‘Syrah’ grapevine in the tropical semi-arid region of Brazil

Effects of leaf removal and topping on ‘Syrah’ grapevine in the tropical semi-arid region of Brazil

Effect of leaf removal on photosynthetically active radiation distribution in maize canopy and stalk strength

The objectives of this study were to determine how the distribution of photosynthetically active radiation (PAR) in a maize canopy affected basal internode strength and stalk lodging. The distributions of PAR within the canopies of two maize cultivars (Zhongdan 909 and Xinyu 41) were altered by removing whole leaves or half leaves in different canopy layers. The results showed that removing whole leaves or half leaves above the three-ear-leaves (RAE and RAE/2) at flowering significantly increased PAR at the ear and interception of PAR (IPAR) from the ear to middle of the ear and soil surface. These changes increased the structural carbohydrate content and rind penetration strength (RPS) of the third basal internode by 5.4–11.6% and reduced lodging by 4.2–7.8%. Removal of the first three leaves below the three-ear-leaves (RBE) before flowering significantly reduced IPAR from the ear to half way below the ear. This reduced the structural carbohydrate content and the RPS of the third basal internode by 9.1–17.4% and increased lodging by 7.0–11.2%. Removal of the three lowest green leaves (RB) in the canopy before flowering increased PAR at the bottom of the canopy, but had no effect on the structural carbohydrate content of the basal internode, the RPS, and the lodging rate. Overall, the results indicated that the key factors affecting the basal internode strength formation and lodging were PAR at the ear and IPAR from the ear to halfway below the ear. Increasing PAR at the ear and IPAR from the ear to halfway below the ear could enhance lodging resistance by increasing the structural carbohydrate content and mechanical strength of the basal internode.

Effect of Leaf Removal on Coloration Improvement of Red variety ‘Hongisul’ Grape

Effect of Leaf Removal on Coloration Improvement of Red variety ‘Hongisul’ Grape

Blackberry Regrowth and Persistence Responses to Defoliation in Mixed Rhizoma Peanut‐Grass Swards

Sand blackberry (Rubus cuneifolius Pursh) is a troublesome perennial weed in Florida rhizoma peanut (Arachis glabrata Benth.)–grass pastures. The degree to which it can be controlled by defoliation is not well understood. In 2011 and 2012, blackberry regrowth and persistence responses were assessed by clipping every 35 d to three stubble heights (8, 16, and 24 cm), with or without simultaneous removal of all leaf from remaining stubble. Blackberry dry matter harvested decreased linearly (12.8 to 8.5 g m−2) as clipping stubble height increased when remaining stubble leaf was removed, but there was a linear increase in blackberry harvested with increasing clipping stubble height (12.1 to 26.0 g m−2) if remaining stubble leaf was not removed. Across stubble heights, cumulative change in blackberry cover across the 2 yr was −15% units if stubble leaf was removed compared with +1% unit when leaf remained intact. As stubble height increased from 8 to 24 cm, blackberry cover increased linearly, both when stubble leaf was removed (−18 to 0% units, respectively) and when leaf remained intact (−12 to +17% units, respectively). In Year 1, blackberry stem density decreased 10 stems m−2 when stubble leaf was removed and 4 stems m−2 when leaf remained intact, but there was no effect of leaf removal in Year 2. Both clipping stubble height and removal of leaf mass affected blackberry regrowth and cover responses, suggesting that combining leaf removal by browsing animals with periodic close mowing will reduce blackberry cover, mass, and stem density.