Any unwanted plant that interferes or tends to interfere with the growth of the individuals of favored species’ is called a weed. Weeding is defined as ‘a tending operation done in the seedling stage in nursery or in a forest crop, that involves the removal or cutting back of all weeds.
- To protect the crops from suppression
- To reduce root competition for moisture and nutrients available in the soil
- To reduce transpirational water loss
- To improve light conditions
It is done at seedling stage. A common practice for weeding is that it must be done before weeds start suppressing the seedling crops and when seedlings have stopped growing in the season. Weeding should be carried out when the weeds have tender roots and shoots, otherwise, it will be difficult to uproot. In plantation, weeding is done during and after the monsoon.
Although number of weedings depends upon the intensity of weed growth and the rate of growth of seedlings of the favored species, three weedings are usually done in first year, two in second year and one in the third year, whereas fast growing species require weeding for one or two years.
In areas where weeds are tall and dense, light cannot reach the ground easily, which not only affect the regeneration but also obstructs the growth of species, because weeds grow at faster rate than the crop species. It can be done in nurseries, natural or artificial regeneration.
In Nepal, it is customary to weed in a circle of 60cm in diameter round the plants, but this should be regarded as an absolute minimum. Increasing the diameter of the circle of one metre would be very desirable. In parts of the Terai and Bhabar Terai Zones where there is a dense growth of perennial grasses, weeding 60cm around the plants is certainly inadequate. Weeds should be pulled to come with the roots. While pulling out, seedlings of desired species should be held firmly between two fingers of one hand in order that they may not be disturbed. During the winter, seedlings need protection from frost. Therefore, weeding should be stopped by the end of September until the start of spring. The intensity of weed growth and rate of growth of crop species determine the number of weeding.
Despite weeding removes all plants that compete with the crop species. Some crop species, by nature, love to have shade-partial or complete while some others are shade tolerant.
Original Article Here