Old And New Damage In Crops

It is important to observe a growing crop closely. Insect and disease damage can occur literally overnight. Farmers must be aware of the condition of the crop at all times. Crop rows may be hundreds of metres long or consist of thousands of individual plants; therefore, one cannot monitor all the plants all the time. It is thus wise that the farmer selects a number of control plants or groups of plants that represent the condition of the plants on a crop field as a whole. These plants should be marked and individually numbered, enabling them to be repeatedly visited and their conditions checked. This process is known as monitoring.

Upon regular inspection, the farmer can visit each of the monitored plants and monitors their condition for the above features. These results of monitoring must be recorded, even if it is only recorded that plants are healthy. If the condition of the plants changes over time, any problem that develops can be managed as soon as it develops.

Regular monitoring of crops is important as it allows the farmer to distinguish between old damage on leaves and fruits that have already been treated and new damage that might need treatment. For example, grapevines may suffer from mildew in late spring when humidity is high. The farmer will treat the crop with a fungicide to destroy the mildew. On revisiting the crop in late summer, damage on the leaves of the grape plant will remain, even though the disease has been treated. Regular monitoring of crops makes it possible to differentiate between old and new damage and infection. Monitoring should also include environmental conditions like wind, rain hail and temperature readings.

There are approximately 200 plant species that make up the world’s most important crop weeds.