Gardener must be keen observer

The deficiencies of plants are expressed in the form of symptoms such as insect attacks, injuries and diseases. The most successful gardener is the one who takes extra care of his plants and uses fertiliser regularly, says Satish Narula

THE deficiencies of plants are expressed in the form of symptoms such as insect attacks, injuries and diseases. Spots or gumming, and drying also portray the state of your garden. The most successful gardener is the one who takes extra care of his plants and is a keen observer. Remember, the best fertiliser for your garden is the dust of your feet.

Insects are an integral part of your garden. Most of then are seasonal visitors. To control them, medicines and chemicals should be used. These are so designed that there is a break in their life cycle at one or the other stage of development. There are certain insects which are almost permanent residents of your garden. They do not attack fruits directly but cause tremendous loss to the crops by severely affecting the normal lifecycle of the tree.

The stem borer or Inderbela species is one such insect. This insect can attack almost all the trees. However, the ones that are the most susceptible are litchi, guava, pear, plants of the citrus species, figs and many ornamental trees such as the pink cassia.

The injury caused to the tree by this insect is multiple. It eats away at the outer bark and skin, thus interrupting the conduction of food. As the habitat of the insect is the main trunk or stems, it also eats into the middle portion of the tree. Certain secretions kill the tissues in the middle portion of the tree, thus disrupting the food channels.

The main contributing cause of appearance of this insect is the irregular pruning of trees by using crude tools or simply breaking unwanted twigs by pulling, leaving irregular cuts or stubs. Neglecting trees is another cause.

How does one identity this insect?

If you see the accompanying picture, you will find a web covering which in fact is the excreta of the insect woven as a web. Under this covering, the insect feeds on the bark. If you start removing the web at the farthest end, it will lead you to a hole in the trunk that mostly ends up in the joints.

After you have located the hole, inject kerosene into it and plug the hole with wet soil. Apply some disinfectant like blitox slurry on the injured and just exposed bark. Carry out the operation in all the trees growing in the vicinity. In case kerosene is not available, use some insecticide like sevin.

Since this is the flowering season for mango, take measures to protect the plants at once or else you will further strengthen the misplaced belief that mango is a failure in this region. This is not the case. Powdery mildew and mango hopper are the major contributors towards these diseases. If allowed to appear unchecked, they can play havoc and cause almost total loss of crop.

As hopper is very active during March, at the time of flowering the nymphs and adults suck the sap from young emerging leaves. How does one identity its attack? Just shake one of the flowering buds on your palm and you will have young nymphs crawling on it. Another symptom of their appearance is that tree leaves and buds become sticky and sooty as if they have been sprayed with gum. Immediately spray one-and-a-half mm of Thiodan 35 EC (endosulfan). Repeat after a fortnight.

Powdery mildew also appears on inflorescence and the axis of the flowering buds. The affected flowers and small fruits along with the flowering branches show die-back symptoms and drop. Karathane can effectively control this disease. It has to be sprayed thrice.

This feature was published on March 28, 1999