Cashew tree rejuvenation for increasing the potential yield in aged tree

• General Observation

    What has been observed in many cashew trees in many cashew nut plantations is; slow growth after some point of time.
   Cashew tree with many primary and secondary branches stands upright but there is no or little vigor and so is no potential yield from such cashew tree. This is affecting the whole cashew nut plantation in terms of yield and profitability.

    The view point of concerned is; the tree has attained the maximum age or age of maturity so is slowly declining in regular and profuse growth even during the favorable condition.
   Many of courses, points out that it was due to lack of proper care that is in terms of maintenance of cashew tree with soil and nutrient management.

   Their justification might be correct on the ground that on attainment of certain growth stage, cashew tree and for that matter; may be many tree species would slow their profuse growth.
  Another justification is; water and nutrient management of cashew nut plantation for achieving the desired yield potential which is also justified.

• Owner’s Expectation

    Plantation owner would expect his or her plantation in the productive scale with potential yield and income. Owner would also want to improve the condition of soil nutrient status and irrigation too when he or she affords to do that thereby maintaining the steady income from the plantation.

    Plantation owner would also want that his or her cashew tree grows well and form a desired canopy for maximizing the per tree yield with increased number of productive branches of the cashew tree.

  But, what many plantation owners do not know or little knowledge is; they do not have any idea other than soil and water management for maximizing the yield or inducing the growth of the cashew tree.
    This is the level of knowledge in most of the cases in many traditional or non-traditional cashew growing area.

    However, there is way out for increasing the vigor of the aged cashew tree to a certain extent for increasing the productivity through scientific approach but it is least tried by most of the plantation owners of the area and elsewhere.

• Scope of improvement

     Expert says; enhanced productivity of the aged cashew tree is possible through top working of ten to fifteen years old tree. The technique is selective removing of unproductive cashew tree branches at the height of two and half meters and inducing the new flush.

   Once the selective removing of the old branches is carried out, new flush grows out at that particular portion. When such new branches are coming up, there will be again selective removing of new shoots keeping the stout new branches of ten to fifteen numbers in the given lot.

    This selected new branches are now meant for further works with a view to achieve the desired objectives of the inducing the growth and thereby increasing the potential yield from the aged cashew tree.

    Now, with that selective top work of the aged cashew tree, you can also train the cashew tree to grow with your desired shape and size of the tree canopy.
    This is particularly required due to the fact that many times due to lack of knowledge by the plantation owners, or some natural reasons, often cashew tree is subjected to the uncontrolled growth means without desired numbers of primary and secondary branches and canopy too. In this case, per tree yield / productivity declines because of un-controlled growth of the cashew tree.

• Owner should do

   Selective removing of the new shoots is used to be done after two or three months from the time of top work of aged cashew tree.
    Once the selective removing is done, the next stage is grafting of the new and selected shoot with desired scion collected from the mother plants of desired characteristics.

    Now the work is grafting of the new shoots with desired scion; collect the scion from the desired mother plants, prepare the new branches or shoots for grafting works by making the longitudinal cut of the shoot after removing the top of the new shoot at the desired height.
    In the meantime your, scion should also be ready, make a slanting cut in the both side of the scion keeping two pairs of alternate leaves at the top.

    Now, place the wedge shaped scion in the stock stem in the provision as narrated above. Tighten the joint portion of the scion and stock with polythene so that no gapping exists in between the joint portion of the scion and stock.

     Keep the newly grafted stem covered with the polythene bag and keep it as it is for one to two weeks for ensuring fusion of scion and stock in the grafted portion. Care should also be taken that there should not be break out at the grafted portion due to gusty wind.

• Expectation of new techniques

    By now, you have done the top working on the aged cashew tree and you have also grafted the stock stem of the aged cashew tree with desired scion from the desired mother plants having good bearing character, profuse branching etc.
    But the point is you can not or you should not go for doing the grafting of the whole cashew tree with desired scion. Actually it should be done step by step and stage by stage. This is to ensure that you are not loosing any fruitful year of the cashew tree whatever may be the present yield potentiality of the tree.

   Usually or it is understood that such grafted stem starts flowering after two years from the time of grafting of the new stem with desired scion. When, it happens, there is bound to be differential yield in terms of total quantity of raw nut per cashew tree even in the aged plantation

• Why it is necessary

    It is often troublesome to maintain the aged cashew nut plantation because of decline in yield and maintenance cost is not commensurate with return from the plantation.
    In that case what happen is; owner of the plantation seems deserting his/her plantation without any care and slowly subjected to the decaying of the cashew tree whole plantation.

    As narrated, with the increase of age of the plantation there would bound to be decline of all growth parameters including yield but there is also way out to tackle the problem to a certain extent instead of thinking for the new plantation to be established in the pretext that old plantation has become unproductive and non-profitable.

    Therefore, cashew nut plantation; for that matter any such plantation of perennial crops should be planned ahead and follow scrupulously in every aspect of maintenance right from the planting stage to maintenance of seedling and training and pruning of the seedling and grown up plants.
   Of course, your water and soil nutrient management will also move side by side along with various other operations or as the case may be.

   Cashew nut plantation owners especially those who are struggling with the aged cashew tree and unproductive plantation should examine and explore the top working techniques for bringing/inducing the vigor in the declined growth of the cashew tree for realizing the better yield and returns for many more years.

                                      Agritangkol dated 17.03.2012