Table of Contents
Operations carried out for the benefits of forest crop at any stage of its life. It essentially covers operation on the crop itself and competing for vegetation and include weeding, cleaning, thinning, felling, pruning, climber cutting, girdling but exclude soil working, drainage, irrigation, and burning, etc.
For the establishment of the regeneration and subsequent development of the forest crop up to harvesting, several operations are carried out. These operations are carried out in the forest crop at different stages of growth in order to provide a healthy environment for their development.
NEED FOR TENDING OPERATIONS:
Two major needs:
2. To provide growing space for trees.
- The act of reducing the chanced of insects and other diseases in sanitation. The trees which are susceptible, injured, broken, weak, diseased, or infected by insects are removed.
- Looking for space in which trees extend their masses, lastly tending operations are essential for providing, the tree with more light water nutrients, etc.
- Tending operations result in the achievement of a form which confirms the human sense of liking.
Any unwanted plant that interferes or tends to interfere with the growth of the individuals of favoured species’ is called a weed. Weeding is defined as ‘a tending operation done in the seedling stage in the nursery or in a forest crop, that involves the removal or cutting back of all weeds.
Objectives of Weeding
- 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
Methods of Weeding
Weeds may be controlled by the following methods:
- a) Mechanical Methods
- b) Biological Methods
- c) Chemical Methods
When Weeding is done?
It is done at the 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 the number of weedings depends upon the intensity of weed growth and the rate of growth of seedlings of the favoured species, three weddings are usually done in the first year, two in the second year and one in the third year, whereas fast-growing species require weeding for one or two years.
Where Weeding is done?
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 a faster rate than the crop species. It can be done in nurseries, natural or artificial regeneration.
How Weeding is done?
In Nepal, it is customary to weed in a circle of 60cm in diameter around 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 the 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.
Weeding Important Points to Note
- The removal or cutting back of any sort of weed growth that is interfering with the growth of the crop is called weeding.
- Removal means uprooting the entire weed even Morus alba if not required.
- Cutting back is meant by cutting the upper portion but this does not control weeding.
- When plants are 3feet high or less, the stage is seedling. In the seedling stage usually, the side branches have yet t come out and light frequently falls upon open interplant spaces and then weeds become active, start competing and start sucking food, hence they are removed.
- Weeds usually come from indigenous spp, some are persistent for example Imperita cylindrical (drub) constantly refuses to leave the land because it is deep-rooted and even plough can hardly do harm to its one feet deep rhizome.
- Weeds mainly appear from seeds, others from coppice and still others form suckers.
- In natural forests, Viburnum spp creates a problem by appearing again and again.
- Weeding should be at early ages because seedlings have to suffer when the weeds surpass them in height.
- For shisham plantation, weeding is done twice in the first year.
- In addition, weeding continues with cleaning as well.
Cleaning is carried out in a crop which has not crossed the sapling stage and is defined as the cutting made in order to face the best individuals from undesirable one of the same age which interfere or are likely to interfere with the growth of the desired individuals.
The greatest advantage offered by cleaning is the proper regulation of the composition of the crop, particularly in mixed crops.
Methods of Cleaning
Methods of cleaning may be mechanical, biological and chemical as described under weeding.
- Tending operations done in sapling crop particularly just before or with the first thinning are involving the removal or cutting back of all inferior growth, climbers, etc” including an excess of coppice shoots and sapling if interfering with better one.
- Sometimes cleaning and the first thing is done simultaneously or sometimes separate.
- Since the sapling branches shade up the ground then weaker type of seedlings may appear, they are undesired and removable.
- Bela plantations of Shisham raised from root suckers and coppices demands cleaning. Here hundreds of coppice shoots are reduced. Here some diseased shisham will also be removed.
- A plant that attaches itself to other plants or objects such as posts and walls as it grows is a Climber.
- This difficulty is faced in nurseries usually seedlings are twined by climbers. Afterwards, the internode increases in length. The climber pulls the head of the seedling. Since this host climber can’t be extended, shoot of the seedling is broken.
- Sometimes it completely girdles the shoots and plants die of suffocation. The climber may ravel itself around the crown, so the victim is devoid of light and food.
- Their removal is necessary.
It is a kind of management of crops at younger and/or older stage in which branches live or dead are removed for further improvement of crops to produce knot-free timber. It is the removal of branches from the trees.
Objectives of Pruning
- To get clear, knot-free high-grade timber
- To meet the demand for fuelwood and fodder
- To get access for inspection and reduce the chance of fire hazard
Kinds of Pruning
On the basis of the kind of branches, pruning is classified into:
- Dry pruning, i.e., pruning of dead branches
- Green pruning, i.e., pruning of living branches
On the basis of the agency of pruning, it is classified into:
Natural pruning: The natural death and fall of branches of standing trees from such causes as deficiency of light, decay, snow and ice. It is also known as self-pruning. Teak, most Eucalyptus species and Kadam are good natural pruners.
Artificial pruning: The pruning done by forester without waiting for nature to do it in dense natural crops or where nature can not do it due to artificially large spacing between stems in man-made plantations to reduce the cost of formation and rotation. It is a costly operation. So, artificial pruning is carried out considering the funds or outcomes.
When Pruning is done?
Trees cease growth during the winter. Therefore, winter is the best season to prune the trees. In other words, prune before the growth starts on trees.
The best time for pruning is when crops are at an early stage of life. Prune when the branches are thin. The time for first pruning should be done between 5-10 years of crop age. Dead branches may be pruned at any time.
How Pruning is done?
In order to get a free timber, cut the branches close to the cambium layer of the stem. Do not leave branch stubs when pruning. Cut on the lower side of the branch before completing the removal with a cut from above. This avoids tearing off the stem. The damage on the stem may help fungus and insects to attack.
Younger trees are pruned at 1/3rd the height of standing tree, while older trees are pruned at ½ of its height. Mature trees can be pruned up to 2/3rd height if fodder and fuelwood scarcity is an acute problem.
Use pruning saw (hand pruning saw or long-handled pruning saw) as far as practicable. Otherwise, local tools- Sickle and Khurpa are equally good but should be very careful while pruning.
The purpose of pruning of fodder and fruit trees
is to increase foliage and fruits, respectively. Pruning of fodder and fruit
trees differ from that of timber objectives. Here, pruning is confined at
secondary and tertiary branches leaving the leading branches untouched.
In a difficult situation, always start cutting from the uppermost branches and work your way down. The lower branches could be used for support.
Pruning is a costly operation. Therefore, it is confined in a pine plantation and fodder trees on farmlands.
For correction and improvements please use the comments section below.
Read Also about Thinning
- OBJECTIVES OF THINNING
- PURPOSE/ AIMS OF THINNING:
- BASIS OF THINNING
- Tree Classification Basis
- CLASSIFICATION ON THE BASIS OF CROWN
- STATISTICAL BASIS
- METHODS OF THINNING
- MECHANICAL THINNING
- LOW OR ORDINARY THINNING
- CROWN THINNING
- FREE THINNING
- ADVANCE THINNING
- NUMERICAL THINNING
- PRECAUTIONS IN FIRST THINNING
- THINNINGS IN IRREGULAR CROPS
- FACTORS AFFECTING THINNING PRACTICE
- LIGHT-DEMANDERS AND SHADE-BEARERS