Technologies for development and plant protection of sloping lands for commercial vineyards

Technology for Developing Slopes and Erosion Control

Developing slopes with a gradient of more than 6–8° is a key reserve for expanding commercial vineyards in warm climate zones. In foothill and mountainous regions, such areas account for about 60% of land suitable for viticulture. When developing them, an agronomist must solve two opposing tasks: to stop soil erosion and to ensure tractor access for vine maintenance. Proper selection of planting patterns and terracing methods allows for reduced operating costs and protection of the fertile layer.

The classification of plots by gradient and recommended methods for their preparation for vineyards are given below.

Slope gradient	Method of land organization and planting	Features of machinery operation and soil tillage
Up to 6° (in some regions up to 8°)	Standard plot layout scheme, similar to flat lands.	No restrictions for standard wheeled and tracked machinery.
From 6–7° to 12°	Contour planting (rows along the contours across the slope). On slopes closer to 12°, wide (20–80 m) embankment terraces are built.	Machines drift downslope. It is necessary to reduce movement speed and shorten the length of the run; it is recommended to avoid using wheeled tractors. Block sizes are reduced.
From 13° to 18–20°	Mandatory construction of terraces 6.5–7 m wide. 2–3 rows of vines are placed on the terrace bed.	Ploughing is carried out with a trench plough across the slope.
Above 18–20°	Construction of bulldozer terraces 4.5 m wide. 1–2 rows of vines are placed on the terrace bed.	Terraces are formed using specialized terracers and bulldozers.

On steep slopes from 13° to 20°, terracing is a prerequisite for establishing a vineyard. The work is performed using a trench plough, strictly observing the technological sequence of passes:

1. Ploughing with a trench plough begins strictly across the slope.
2. The first pass is made at the very bottom of the terrace being marked.
3. The plough is gradually moved up the slope until a bed 6.5–7 m wide is formed.
4. Vines are planted in 2–3 rows on the finished terrace.

To protect the soil from erosion on all types of slopes, row spacings are kept under sod or sown with green manure crops. Earthworks on steep plots are approached in stages. Development begins with gentle slopes as they are the easiest to manage, and only then moving on to more complex terrain.

Traditional Vine Training Systems

The vine training method determines how efficiently the vineyard uses light, air, and soil nutrients. A properly selected support provides canopy ventilation and allows for the mechanization of pruning and tillage. Along with modern trellises, in arid or specific regions, traditional systems are still used — ground spreading and tree training.

• Area of suitable slopes over 6–8° — more than 6.5 million hectares
• Potential for expanding plantings in the south — 120–160 thousand hectares
• Width of the ridge for single-row spreading — up to 3 m
• Width of the ridge for double-row spreading — 6–7 m
• Height of stakes/supports for shoots — 50–70 cm
• Depth of irrigation ditches — up to 50 cm

The spreading system is used in arid regions with a deficit of precipitation during the ripening period. It is suitable for seedless table grape cultivars intended for drying (sultanas), as well as for rootstock nurseries for phylloxera-resistant cultivars. Vines are formed without a trunk or on a low trunk, spreading shoots in a fan shape along the ground or on low supports.

To increase efficiency, an improved spreading method (bogaz or mound system) is used. Vines are raised on Y-shaped stakes or poles 50–70 cm high, and the vines themselves are planted on elevations near irrigation ditches up to 50 cm deep. The method saves money on trellis installation and guarantees high sugar content in berries due to solar exposure. However, it precludes full mechanization, and if it rains, the clusters get soiled by the soil and rot.

Training vines on trees (alberata, magliari, dobiro, chiovan) uses living trees, mainly fruit-bearing ones, as supports. Wire is stretched between them, and vegetable or industrial crops are grown in the row spacings. The method is practiced in home gardens in non-covering zones for hardy cultivars, such as Isabella. The system has serious drawbacks: the plants suppress each other, the canopy becomes dense, the vine ripens poorly, and maintenance and harvesting require manual labor.

Fig. 39. Grapevine training systems:

/ — ground training; 2 — tree-trained; 3 — trunk (bush) training; 4 — stake training; 5 — Uzbek arch; 6 — voish; 7 — single-sided pergola; 8 — double-sided pergola; 9 — alley training (dimensions in centimeters).

The trunk (bush) system is known in Europe, America, and the USSR (Turkmenistan and other regions). The trunk serves as the support for grape plants. It is used in non-covering viticulture zones. This system is economical, as artificial supports are only necessary during the plant formation period and tying is eliminated. Bush productivity is high due to good light exposure. Clusters are protected from sunburn by the canopy of leaves, and annual shoots suffer less from frost. However, mechanization of work is difficult, especially in the second half of the growing season.

Stake system. In the USSR, it has been preserved in old plantations and on household plots in Moldova, Georgia (known as dablari), the North Caucasus, Ukraine, and the Don region in two variants:

• 1 — cordons and shoots are tied to a single stake (Crimea, Georgia), whereby the canopy is dense and light utilization is limited, resulting in low bush yield;
• 2 — cordons and shoots are arranged radially and tied to many (up to 30) stakes (Moldova, Rostov Oblast of the RSFSR).

The use of solar radiant energy, bush productivity, and harvest quality are high, but mechanization of plant maintenance is difficult.

Arbor and trellis systems. The oldest of these, known since Ancient Egypt and preserved in Central Asia, are the gallery types — the Uzbek arch and voish. In this case, cordons and shoots are placed on rods, wire, or inclined trellises made of poles. These systems are used for vigorous cultivars of the Oriental grape group.

In recent years, they have been improved and named improved voish and alley training systems. The R. R. Shreder Research and Production Association for Horticulture and Viticulture has proposed several of their types, used between plots, on main roads, etc. With these systems, the soil is shaded during the growing season, which creates favorable conditions: leaves utilize radiant energy more fully, soil overheating does not occur, berries are not sunburned, and weeds do not develop, which contributes to increased plantation productivity. They also have decorative value.

A system known as pergola (Ital. pergola — canopy, extension) is widely known in South America, the USA, Australia, Germany, France, Italy, and Yugoslavia. It can be single- or double-sided and has various designs.

Vertical trellis. Introduced with the advent of wire, it is still considered perfect for commercial plantations. With this system, vertical supports are installed along the rows and wire is fixed horizontally on them in rows (2–5 or more), which requires certain labor and financial costs for supports, but allows for the mechanization of all processes, including harvesting of the harvest and pruning, as well as disease and pest control. The efficiency of solar radiant energy utilization is high. This improves canopy ventilation and increases plantation productivity and product quality.

The trellis can be single- or double-plane, umbrella-shaped, or a truncated quadrangular pyramid (recommended for the Don). The double-plane trellis is used for vigorous cultivars in regions with good moisture supply or under irrigation conditions, with large feeding areas (3–4 m), on fertile soils in Central Asia, Moldova, Ukraine, and the Don region. Yields increase due to the large mass of leaves and reproductive organs per unit area, but maintenance of the bushes becomes more complicated when the canopy is dense.

Horizontal trellis. Known for a long time. It is widely used in non-covering culture zones in Australia, India, South America, Japan, Algeria, Yugoslavia, Austria, France, Spain, Italy (called tendone), and in the USSR — in commercial vineyards of Central Asia and on household plots in the RSFSR, the Ukrainian SSR, and Georgia in the case of growing vigorous table grape cultivars with a high trunk and a large number of cordons. With this system, also called trellis training, high trunks (1.8–2.6 m or more) are formed, and the canopy is placed in a horizontal plane on a wire grid or a frame of wooden beams fixed to supports. The clusters are located under the leaf canopy, which protects them from sunburn.

Combined trellis system combines vertical and horizontal trellises. It can be L-, T-, or U-shaped in form, and single- or double-sided. The trunk, perennial branches, and part of the fruit-bearing shoots are placed in a vertical plane, while the main number of shoots with leaves and clusters are on an inclined (at an angle of 15–30° or more) or horizontal surface on crossbars with parallel rows of wire (2–3 or more). Sometimes the crossbars are hinged, which makes the system more mobile.

This type includes the trellis with a canopy, common in Central Asia, featuring wide row spacing (3–5 m). In this case, plant productivity increases by 25–40% compared to a vertical trellis due to better leaf exposure to light, which protects the clusters from overheating.

Fig. 40. Trellis training systems:
1 — vertical single-plane for low-growing forms; 2 — same for high-trunk culture; 3 — double-plane; 4 — horizontal: a — tendone, b — T-shaped, c — inclined; 5 — combined: a — G-shaped, b — T-shaped, c — U-shaped, d — with a canopy (dimensions in centimeters).

Overhead trellises are being tested. Work continues on improving other bush training systems, and many new modifications are available.

For rootstock cultivar stool beds, the following bush training systems are used:

Criteria for selecting a bush training system

It is important to distinguish between the shape of the bush and its training system. The same shape in different ecological conditions requires its own training system, and vice versa — one system can be suitable for different bush shapes. When choosing a training system, one focuses on the vigor of the cultivar and rootstock, soil type, humidity, and the planned harvesting method. For vigorous cultivars on fertile or irrigated lands, robust combined, horizontal, or 4–5-wire vertical trellises are installed. Low- and medium-vigor vines are sufficiently served by low trellises with 2–3 rows of wire.

The trellis structure directly changes the phytoclimate inside the bush: lighting, temperature, and humidity. A high trunk with free shoot positioning improves leaf lighting, which activates photosynthesis and increases yield. At the same time, near the soil surface, the daily temperature amplitude is higher, which accelerates berry ripening and sugar accumulation. However, in hot regions (Armenia, Azerbaijan, Central Asia), proximity to the soil threatens the clusters with burns from soil thermal radiation, so the canopy is raised higher here on combined or horizontal trellises.

In areas at risk of frost, the canopy is also raised, as cold air collects near the soil surface at night. This reduces frost damage to buds compared to low-trunk formations. In humid climates (Sochi, Transcarpathia, Western Georgia), surface air retains moisture, triggering outbreaks of fungal diseases. In such conditions, bushes are placed high, and the canopy is regularly thinned for better aeration.

For technical cultivars intended for drying in arid regions, supports may not be used at all. Here, the vine is trained in a sprawling manner, on a mound, using the bogaz system, or on a low vertical trellis with 1–2 rows of wire. Table cultivars require larger and more powerful training systems than technical ones. For combine harvesting using the vibration method, a vertical trellis with a clearly defined cluster zone is installed.

• Humidity difference near the soil surface — 6–10% higher
• Canopy raising height against frost — by 20–50 cm or more
• Cluster zone for combine harvesting — 60–150 cm from the ground
• Low trellis parameters — height and width up to 50 cm

Vineyard supports and risks of working without trellises

Growing grapes without supports complicates all technological processes in the vineyard. Shoots lying unsystematically on the ground interfere with pruning, tillage, and protection against weeds, diseases, and pests. Clusters come into contact with the soil, become dirty, and have poor air circulation, which causes them to rot quickly. Furthermore, during mechanized operations, tractors and implements damage the vine, reducing total yield.

Support material is selected based on the economic capabilities of the farm and the adopted technology. Wooden, metal, reinforced concrete, synthetic, or combined posts are installed in vineyards. Specialized types of bush training are applied to rootstock cultivar stool beds.

• Sprawling training system.
• Low horizontal T- and U-shaped trellises with crossbars and 2–4 rows of wire.
• Vertical 4-wire trellis with vertical or inclined shoot tying.
• Pyramidal system with four wires attached to a vertical support.
• Vertical 3-wire trellis.

Material selection and preparation of supports for installation

The service life of a trellis depends directly on the quality of the post preparation. If young and moist wood is used without prior treatment, it will quickly rot under the influence of soil moisture and microorganisms. Various wood species are suitable for vineyards, but each requires an individual approach to preparation.

Wood species	Service life without replacement (years)
Yew, larch, oak, eucalyptus, chestnut, acacia, mulberry, plum (without sapwood)	15–30
Linden, pine	10
Fir, spruce	10
Poplar, alder, maple, birch, willow	up to 4

To protect wood, coal and shale oils, petrochemical waste, softwood tar, creosote, carbolineum, or petrolatum (with an application rate of up to 90 l/m³) are used. Water-soluble heavy metal salts are also utilized: chromated-fluorated-arsenates (ACA preparation) and chromated-copper-arsenates (CCA preparation). The post preservation technology consists of three sequential stages.

1. Drying before treatment. Before impregnation with oil and salt compounds, the wood is dried to a moisture content of 20–25%. Pine posts are dried more thoroughly — until cracks appear, into which the antiseptic penetrates deeply.
2. Impregnation. Compounds are applied so that they penetrate deep into the wood structure by at least 3 cm. The lower pointed part of the post is treated to a height of at least 70–80 cm from the edge.
3. Fixation of the protective layer. After the bath, the posts are dried outdoors or in dryers for 2–3 weeks or more. The preparations will be securely fixed in the wood when its surface moisture content drops to 8–10%.

Besides wood, alternative materials are used in vineyards. Metal supports are made from pipes, angle iron, T-bars, or I-beams. They are durable but require protection against corrosion by galvanizing, calorizing, or applying several layers of drying oil. Hollow metal posts are filled with concrete from the inside for stability and mounted on a concrete plinth. The metal consumption for one such support is 3–8 kg.

In recent years, synthetic supports made of polyvinyl chloride-polystyrene and plastics have become an alternative to traditional materials. They are 200–210 cm long and 6–8 cm in diameter. Currently, such structures are undergoing testing at domestic research institutes.

Design and installation rules for support structures

The parameters and depth of post installation depend on the adopted vine training system. The load from the green mass and harvest is distributed unevenly along the trellis elements, so end and intermediate supports are installed according to different rules.

• Service life of concrete supports — 60–80 years
• Installation depth of stakes — 30–40 cm
• Installation depth of end posts — 40–70 cm
• Mass of stone anchor — 10–12 kg
• Inclination angle of end posts — 60–65°

With the stake system, wooden stakes 4–7 cm in diameter and 1.25–2.5 m long are buried in the soil to a depth of 30–40 cm using post drivers. In regions of cover viticulture, stakes are dug up for the winter and stored in stacks under a shed. In non-covering and arid regions, they are left in the field. With a high-trunk culture, a trunk support post 5–10 cm in diameter and 1.5–2.5 m high is installed next to each plant. It serves as a support for the trunk for 6–11 years.

The trellis system requires the installation of two types of posts:

• End (anchor) posts. They bear the main tension of the wire. Their length is 1.8–3 m, cross-section — from 7.5 to 20 cm, installation depth in the soil — 40–70 cm.
• Intermediate posts. They support the vine within the row. Their cross-section is smaller — 5–12 cm, length — 1.5–2.5 m, and the installation depth is 10–25 cm shallower than that of the end posts. The distance between them is 8 m, and only on plains for low-vigor cultivars can it be increased to 8–12 m.

On arbors, galleries, and avenues, posts 3–5 m high with crossbars are used. They are placed with a spacing of up to 8 m along the row, with wire tensioned every 50–80 cm. The width of the passage between avenues is from 2 to 4 m or more. In a combined trellis, cross-rails 6–8 cm in diameter are mounted on vertical posts at an angle of 15–30° or horizontally. 2–3 rows of wire are attached to them. A horizontal trellis involves assembling a grid with cells up to 50 cm on a frame-structure, fixed to sturdy supports.

Special attention is paid to the stability of the end posts. They are mounted strictly vertically or inclined outward from the row (towards the road) at an angle of 60–65°. For fixation, braces made of thinner posts are used, installed at an angle of up to 60° from inside the row, or screw anchors and rubble stone. Heavy anchors are also used: stones weighing 10–12 kg or concrete blocks up to 30 cm in diameter are buried to a depth of up to 1 m, at a distance of 70–100 cm from the end post towards the road.

It is most reliable to install vineyard supports immediately after planting nursery plants; however, in practice, this work is often postponed until the second year, completing the installation before the start of the growing season. Machines KRK-60 and KYaU-YuOA are used for digging post holes. The installation of supports in the field is carried out by the universal post driver SP-2 or the double-row post press ZSV-2, and on slopes in mountainous conditions — by the specialized unit SVG-1 V.

• Depth of post holes — up to 60 cm
• Installation of supports with post drivers — 90–200 units/h
• Unwinding of wire with the UNP-6 machine — 0.2–0.5 ha/h
• Tensioning with the LRD-85 winch — 0.1 ha/h

To create a long-lasting trellis, choose galvanized or zinc-coated wire. Options in polyvinyl chloride (plastic) coating or strong synthetic threads are also suitable. The thickness is selected according to specific tasks. For the lower tier of the trellis, in high-trunk training systems, for fixing anchors, and when growing vigorous cultivars, wire with a diameter of 3.5–6 mm is used; for the upper tiers, 2.5–3 mm is sufficient.

1. Unwinding. Use a crossbar with a wire drum and reels or a special UNP-6 machine with two mounted platforms and 6 guide pulleys, which lays 3–4 wires on two rows in one pass.
2. Tensioning. Tension the wire using levers, "Grip" devices, blocks with two conical leaf springs, or LRD-85 dynamometric winches.
3. Observing the sequence. Always start tensioning from the top row of wire, then sequentially move to the lower ones.
4. Fixation. Secure the tensioned rows to the intermediate posts.

Placement of wire on the trellis and maintenance of the structure

The layout of the wire depends on the biology of the cultivar, the vigor of the bush, and the adopted cultivation technology. On the posts, the wires can be fixed rigidly or remain movable. Practice shows that double wire is more convenient than single: it allows you to simply insert growing shoots between the wires without additional tying.

In the zone of cover viticulture, on a vertical trellis, the bottom row is tensioned at a height of 30–60 cm from the soil level. The exception is the long-arm fan training system of the bush, where the bottom wire is raised to 140 cm due to the risk of frost and high air humidity. Each subsequent row is placed 30–60 cm above the previous one. In total, two to five rows of wire are mounted, depending on the vigor of the bush.

In the non-cover zone, the first row of wire with a diameter of 3.5–4 mm is tensioned strictly at the height of the trunk — from 80 to 160 cm or more. The second and subsequent rows are placed higher with a spacing of 25–50 cm. The distance between the wire rows and their total quantity are determined by the shoot vigor of a specific cultivar, the bush shape, and the cultivation technology.

For high-trunk wide-row culture with free hanging of the growth, the trellis is assembled from only one or two (rarely three) rows of wire, which eliminates the need for manual shoot tying. The first load-bearing thread with a diameter of 3.5–6 mm is tensioned at the level of the trunk for attaching horizontal cordons. Two parallel wires with a diameter of 2–2.5 mm are stretched 15–30 cm above it, with a distance of 8–25 cm from each other. If these two threads serve as a support for the spurs from which the shoots hang freely downwards, the manual labor costs in the vineyard are reduced by 2–3 times.

Annually, during the dormant period of the bushes, carry out a planned repair of the trellis. During this period, it is necessary to straighten leaning posts, replace broken supports, fix breaks, and tighten sagging wire. Plan all work in advance. To quickly extract damaged posts and install new supports to a depth of 50–70 cm, use the ZSV-2 machine.