Hand weeding

In organic systems the number of hours of hand weeding needs to be reduced, as labour, particularly in the developed countries, is expensive. This can be achieved by competition, the timing of cultivations, adaptation of the rotation nutrient management system and by crop density (Kropff, et al., 2000). Barberi, et al. (2002) experimented with a system of soil disinfection using hot steam to sterilise weed seeds. 

Weed control Sterile substrate 1 x hoeing, 1 X hand weeding... 

II period emphasize hand weeding and immediate reseeding of all areas of weed growth. 

Recycling weeds Hand-weeding may seem like a chore compared to the application of sprays, but when those weeds are composted, all the energy and nutrients they have taken from the soil can be returned to the garden without any taint of chemicals. 

Left) Hand-weeding If you hand-weed regularly, and the soil is moist, you can develop a quick "nipping" action that makes weeding almost pleasurable. Weeds that have only gained a superficial foothold in a loose mulch are particularly satisfying to remove. 

Paths and patios can aiso be hand-weeded. There are toois speciaiiy designed to heip pry weeds from cracks between paving siabs. 

Five weeJcs after sowing, the broccoli was transplanted into the field while wild mustard was planted directly on the date of broccoli transplant. The area was irrigated every wee)c with overhead sprin-)clers throughout the experiment and fertilized 10.1 L/ha fish emulsion ("Grow Force brand) at 30 and 57 days after set-up of the experiment. The plots were hand weeded selectively every 15 days, samples of the volunteer weeds were ta)cen through the plot method (18), and the number of different species, number of individuals of each species, and biomass (dry weight) were recorded for each plot. The dominance, frequency, density, and importance value were calculated for each species in each plot. 

Hand weeding in forest nurseries is an expensive operation, and nurserymen are constantly on the lookout for cheaper methods of controlling weeds. 

Weeding done exclusively by hand often involves from 80 to 120 man-hours per acre. Current labor costs in our northern nurseries are at least 85 cents per hour. At 100 man-hours per acre, costs of hand weeding would be 85 per acre, which is indeed a sharp contrast with the cost of weed elimination with mineral spirits, which can be done at only 21 to 27% or less of the cost of hand weeding. 

As the industrial revolution drew workers from the fields to the cities, it became more difficult to rely on hand weeding to keep weeds at bay. 

It is important that herbicides used for weed control in crops are selective to that crop. Early compounds used the inability of the foliage of upright cereal crops to retain a great deal of spray as the basis of their selectivity and this was successful in many situations although it must be remembered that the alternative to weed control with inadequately selective herbicides was hand weeding or no weed control at all. 

The move into continuous cereal production and away from mixed farming with firm rotations meant that farmers could cultivate high value crops on all available land without the need for fallow. This could not have been achieved without the use of chemical herbicides. The movement of people from the land to the urban environment during the industrial revolution and thereafter reduced the available labour for hand weeding and weed control became a real problem for the farmer. The revolution was the introduction of 2,4-D and MCPA that allowed broad-leaved weeds to be controlled selectively in the previously dirty cereal crops. 

In many agricultural enterprises, organic farmers may use fewer inputs such as fertilisers and pesticides and sometimes more labour, such as for hand-weeding, than on conventional farms. This is not necessarily the case, as materials to manage nutrients and pests on organic farms such as mineral fertilisers, compost and pheromones can also be costly. 

The historical record reveals that herbicides have replaced or reduced the use of hand weeding and cultivation for weed control, with an associated reduction in cost and an increase in yield. Today herbicides are used routinely on more than 90% of the area of most US crops, representing 87 million ha of cropland (Gianessi and Reigner, 2007). 

Historically, tillage and hand weeding were the main methods of weed control. Since the advent of herbicide use in 1950, essentially all sugarcane in Australia now receives one or more herbicide applications. Virtually all of the crop is produced on family-operated, commercial-scale farms and is processed at cooperative or privately owned mills. 

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