Operations: the importance of hoeing machines
For achieving excellent cultivation, especially for widespread crops, the careful aeration of the soil surface is required. There are differing technological solutions for this operation for various soil types and the specific requirements for each crop. The Italian industry markets a wide range of models which combine efficiency and flexibility
The definition hoeing crops refers to such species as corn, sugar beets, soya, tobacco and numerous vegetables which draw special benefit from this crop practice. In substance, this consists of refining and remixing top soil between rows to gain these advantages which include: breaking the surface crust to stop the vertical capillary action created in specific soil types as the result of prolonged periods of drought which aggravate water deficit conditions; otherwise, in opposite conditions of precipitation, hoeing allows the uniform incorporation of rainfall for better absorption of the water by the upper part of the root apparatus and reducing superficial drain off, one of the causes of erosion; effective mechanical hoeing is a valid alternative to the application of chemical products. This is an opportunity which sometimes becomes obligatory in conditions when weeds are resistant and difficult to control adequately, especially in long-term single-crop conditions. The mechanical alternative, of great value for the organic treatment of cultivations, appears to be the real reason for rediscovering mechanical weeding for a substantial reduction of impact on the environment caused by traditional weeding with synthetic products.
Hoeing machines
These machines pulverize the top 4-8 cm layers of soil between rows which has been somewhat compacted by the passage of agricultural machinery and rainfall and alternating dry periods which dry out the superficial layers.
Top crust is broken up by a series of tines or forks which differ according to the soil type. The working components are solidly mounted on the ends of the toolbars with a curled configuration to take advantage of floating for working the soil to pulverize, which becomes more evident depending on the forward speed. The work speed has a wide range, from about 5 up to 12 km/h.
Each hoeing machine component can carry more than one working tool whereas these are from 3 to 12 depending on the work width of the machine. For ensuring the ability to operate on small irregularities of the soil profile, each component is mounted on a parallelogram frame floating frame for vertical oscillation and the principal toolbars are mounted on the structure of the hoeing machine on Teflon or hardened steel sockets with a low wear coefficient, often sealed and lubricated with dedicated greasers. The depth of work is set by the use of metal wheels, or those with rubber coatings, which rest on the ground. They can be vertically micro-regulated in relation to the machine’s main frame by a handle.
Sometimes the machine is equipped with a support chain to hitch to the third point of the lift to ensure stability in operations.
To allow the hoeing machine models with the greatest work width to be transported on roads there are methods for reducing size either manually or with hydraulics. In some cases, with widest components can be partially or totally folded over the fixed components and rotated by 90° or 180°, for some models, can be elevated without folding.
Complementary operations
Hoeing calls for one or more transits in the field towed by a tractor sometimes in combination with other work, typically for spreading fertilizer (often nitrogen) and/or earthing up, or ridging, the soil, especially when superficial rootstock must be strengthened, when potato tubers must be covered or to blanch some vegetable plants such as thistle, fennel, celery, radishes. Ridging also enhances weeding because the soil brought up suffocates the weeds which have grown close to stems and stalks. Moreover, the furrow created between rows are usually not large enough to interfere in successive operations, basically harvesting, and can be used for lateral irrigation if necessary.
Special accessories
As would be expected, hoeing machines can be equipped with a wide range of accessories for the purposes of some complementary operations and/or making work more efficient in difficult conditions. The tasks most coupled with hoeing machines are distributing mineral fertilizers and ridging. For these operations, the machine is equipped with a central hopper and centralized regulation of dosages or dedicated distributors on each of the machine’s components activated by a toothed wheel running on the ground. The granules of fertilizer are distributed through a flexible conveyor tube and sent into the soil with the work of the machine’s anchors. For work on heavy ground, some models can be equipped with weighted springs to facilitating breaking up the soil.
On the other hand, ridging is performed by the hoes, more or less divergent pairs of free-wheel plain or serrated discs or small ditchers with mouldboard. With the proper regulation of the position of frame of the machine the hoes can be used to increase the depth of work. In this connection, Spapperi in San Secondo near Perugia markets the multi-functional machine built for tobacco crops combining weeding, fertilization and earthing soil. This latter operation is performed by pairs of rotating steel cones which work the soil energetically and possibly completes the operation with hoes working in the center of the rows.
Protection of shoots
Hoeing is often done when plants are in early growth of the crop and very sensitive so it is important to protect them. Generally available for this purpose are three types of devices, guards, serrated discs and plain discs.
In any case, the purpose is to create a barrier between the plants and the earth ridged by the working tools to avoid any possible mechanical shock due to impact of clods against the shoots or the spread of soil on the stems or tiny leas.
Organic weeding
A solution somewhat distanced from traditional methods has been taken up by Badalini in Rivarolo Mantovano near Mantua which markets models with the usual components of anchors with free rotating discs equipped with radial projections rather than divergent curves to optimize moving the soil. The axis of the rotation of the discs becomes inclined off the vertical to combine weeding and a degree of ridging, especially if the discs are mount to converging pairs on the sides of the crop rows being worked. The forward speed advised is 3-5 km/h and the best cleaning action comes in the first phase of plant growth.
Metal-Co in Cigliano in the Vercelli Province, turns out weeder-ridger machines for working terrain with a high value of large particles. The main tool components are a combination of pairs of free rotors working at converging angles equipped on their circumferences with pairs sturdy radial rings which works the soil. Cleaning and protecting the shoots, if necessary, is done with other pairs of free serrated discs which work the soil perpendicular along with convex discs.
The Remoweed
by Ferrari Costruzioni Meccaniche
Excellent weeding means not only breaking up the inter-row soil surface but also pulverizing the soil between the plants and a next row. The greatest importance of this work is when the plants are in their earliest stages of growth, especially for efficiently combating the competition of the weeds. Above all, these operations are advised for certain vegetable crops which are damaged by the aggression of fast growing alien species not only taking up nutrients but also blocking the light. Ferrari Costruzioni Meccaniche in Guidizzolo, near Mantua, has come up with the Remoweed, an automatic inter-row and inter-plant weeder with a floating frame which can shift right and left with the use of hydraulic pistons. The machine is equipped with units which correspond to the number of rows and each unit carries a pair of hydraulic arms holding the two cutting blades which work at a height regulated by the operator. The opening and closing cutting speed is automatically set according to the forward speed of the machine and soil type and each unit is equipped with an infrared optical bar which detects weeds and plants.
