Weed control in sugar beet by precision guided implements

Abstract

A field experiment was carried out in sugar beet with a wide-span (12.2 m) tractor and laser guided implements. By means of a side-shift facility, implements were mounted on this vehicle for seedbed preparation, drilling, fertilizing, spraying and hoeing. Automatic laser guidance was possible with an accuracy of 0.6 em on a track length of 220m on arable land.No inputs (soil cultivation, fertilizer, herbicide) were made at places where they were not needed, or even would potentially pollute the environment. The aim of the experiment, which was carried out in 2 successive years on fields of the same farm, was to investigate the influence on weed occurrence and efficiency of weed control.Leaving out seedbed preparation between the future crop rows left already germinated weeds alive. In 1 year pre-emergence application of paraquat-diquat was necessary to stop growing of well developed weed plants. A crumbling operation had to be carried out to break the clods, otherwise inter-row hoeing was impossible. From the viewpoint of weed control restricting seedbed preparation to the future sugar beet rows was not of advantage.Precision guidance allowed enlargement of mechanical weed control, i.e. interrow hoeing to 80% (40 em wide at a ·row distance to 50 em). Savings on herbicides were 75%, because little overlap was necessary of chemically and mechanically treated areas. The absence of fertilizers in these inter-row bands did not diminish the number of weeds, and speed of emergence of weeds. The effect of seedbed preparation and drilling the sugar beet crop in complete darkness (at night), made possible by the automatic guidance, on weed infestation was not different from daylight treatments. In these experiments this so called photo-control of weeds was only demonstrable after hoeing.Keywords: weed control, precision guidance, photo control Many agricultural crops are grown in rows with interrow distances that vary between 0.25 and 0. 75 m. Intra-row spacing is often far less, varying from 0.05 to 0.5 m. This means that on both sides of a crop row, there are bands of soil which serve as spacer bands only. Nevertheless, these spacer bands are crumbled, fertilized, sprayed and treated as part of the crop. the rows. Both ways require some form of intelligence and automation, the first to detect the spots where the sugar beet plants are growing, the second to guide the hoe very closely along the sugar beet rows. Bontsema, Grift and Pleyzier (1991) did research on how to distinguish the sugar beet plants from weeds, to make it possible to swing a hoeing knife through the row of sugar beet plants. Laser guidance of the hoeing implement, and prior to that of the sowing machine used in this experiment, make it possible to approach the row of sugar beet plants very closely without risk of damaging them.To lower the dependency of farmers on the use of chemicals, and to decrease the overall use of chemicals by half in the year 2000 (MJP-G, 1992), research has to be done on alternative weed control methods. Band spraying is an opt...

Non‐chemical weed management in organic farming systems

“…A second operator or some form of self‐steering mechanism may be needed to minimize crop damage (Bowman, 1997). Laser transmitters and receivers have been used to guide machinery in a straight line, allowing weed control and other operations to be made day or night (Van Zuydam et al ., 1995). More sophisticated guidance and weed detection systems, which were developed originally for precision pesticide application (Miller et al ., 1997), have now been applied to mechanical weeding implements (Tillett et al ., 1999).…”

Non‐Chemical Weed Management

“…Laser transmitters and receivers have been used to guide tractor mounted machinery in a straight line across a field (Naber et al, 1992;van Zuydam et al, 1995). With this system, seedbed preparation, mechanical or chemical weed control, or fertiliser operations could be carried out day or night.…”

Seed Mapping of Sugar Beet

“…They require presumably different cultivation principles as there are (i) the area between the rows (inter-row area), (ii) the area between the crop seedlings within the rows (intrarow area), and (iii) the area close to and around the crop seedlings (close-to-crop area). Inter-row treatments such as hoeing, harrowing or brushing are mature methods and have reached a high level of automation even with automated guidance systems within recent years (Van Zuydam et al, 1995;Tillet et al, 2002). The challenging tasks are still to spatially control either chemical or physical treatments within the intra-row and close-to-crop areas.…”