Weed Management in Beets 
Three cultural types of beets (Beta vulgaris) are commonly grown in the UK including sugar beet grown as a field crop, fodder beet grown as a field crop for its roots and foliage for animal consumption, and beetroot, red or table beet grown as a vegetable crop outdoors or under protected conditions for the edible roots. Weed management practice will depend on which beets are being grown.
Beetroot:the optimum time for weed removal is around 3-4 weeks after crop emergence. Once the weeds have been removed the crop has some capacity for recovery from a check to growth due to the weeds Land should be free of perennial weeds. Conventional primary and secondary cultivations are used to establish the crop. False or stale seedbeds will reduce weed numbers in the growing crop. As with sugar beet (see below), once the crop has emerged, regular inter-row cultivations with brush weeders, ridgers, steerage hoes, finger-tines etc will deal with weeds between the rows. There will be some effect on intra-row weeds but hand weeding may be required.
Fodder beet: may be drilled or broadcast. Punch planting makes use of the stale seedbed technique but minimises soil disturbance even further by dropping the seed into holes made by a dibber. This technique has been shown to reduce weed density by 30% compared with a normal drilled crop. Pre-emergence flaming has been shown to reduce weed numbers by 34 to 44 %. However, in relatively low value arable crops such as fodder beet that are grown on a large scale the cost of flame weeding may not be justified.
Sugar beet:Sugar beet usually follows a grass/legume leys or a cereal in the rotation and precedes a cereal or some other crop that will benefit from the residues of any manure application. Sufficient nitrogen from manure or compost application is important to ensure rapid the leaf development that will provide a dense leaf canopy and shade out the weeds. The primary and secondary cultivations required for seedbed preparation will have a considerable influence on the weeds. However, the nature and timing of these cultivations will vary with the previous crop, with soil type and with soil condition at the time of any operation. In general a level crumbly seedbed will give the crop the best start but growers may want to keep cultivations to a minimum. Weeds tend to emerge better and in greater numbers from a fine seedbed than a coarse one, but control measures are often more effective on a fine level seedbed.
It is important to achieve a good crop stand, as it is the dense leaf canopy that shades out emerged weeds and inhibits later flushes of seedling weeds. As the crop canopy does not close fully until mid-summer and tall growing weeds such as fat-hen and certain mayweeds may grow above the canopy before it closes. In the UK, the optimum weeding period is between 4 and 6 weeks after 50% crop emergence. In practice, weeding operations should commence at the 4-6 leaf stage and may cease at around the 10-12 leaf stage. Once the optimum weeding time has been reached yield may be depressed by 1.5% for each day the crop is left unweeded, although sugar beet has some ability to recover from an early check.
Sugar beet cultivars vary in their growth habit, some have an erect leaf rosette (cv. Carla) others have a more horizontal leaf arrangement (cv. Lucy). Weed seedling survival can be much less with the latter, demonstrating the importance of early ground cover establishment. A stale seedbed may be prepared 10 days in advance of the drilling date and the weeds killed by shallow cultivation before drilling. There is a risk of the seedbed drying out resulting in erratic germination when the crop is sown. Light harrows may be used after drilling either on the flat or to level the ridges due to drilling, but this may reduce plant stand. Mechanical inter-row cultivation is important in early control of weeds. However, cultivation stimulates further weed seedlings to emerge. Spring-tine weeders can be effective in sugar beet at low weed densities when the soil is drying and weeds are unlikely to re-root. The crop must have at least 6-leaves to withstand the tine weeder but must not be so large that the leaves catch on the tines and pull the crop out. Intra-row weeds are more difficult to deal with. The torsion weeder at low intensity has proved to be relatively gentle on the sugar beet crop from the 4
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