09/08/2013

Treatment of trees with tall stem (in vertical) with the mist blower

An important aspect, but little considered, is the correct configuration of the mist blower in accordance with the application to be performed; anything but complicated, and by reading this article maybe you will find out something of your mist blower that you didn’t know before.

The mist blower Cifarelli (both the models M3A, L3A and the M1200) is endowed on the throwing pipe, with a spreader with the shape of a truncated cone.
This spreader, that serves for widening the air flow, can be assembled and removed in relation to the cultivation to be treated.


For applications to ground crops (potatoes, vegetables), in espaliers (vineyard, tomatoes etc..) or on trees up to a height of 7/8 meters, it is recommended to use the mist blower with the spreader installed because by enlarging the jet will amplify the treated area, speeding up the work.

In case of treatment of tall trees (higher than 9/10 meters) you have to remove the spreader: of course by doing so the outflow narrows, but picks up speed, increasing the range of about 2 meters, so the presence of the spreader affect the possibility of treating about 2 meters more.

Up to which height I can treat?

On the informative leaflets of the mist blowers, the manufacturers declare the value of the maximum range, both in horizontal and in vertical (not always).

It is important to know that such value is the distance where some nebulized drops arrive; their number, however, is not enough to protect the crop from the disease or insect attack.

The important value is the optimal range reached, that is the distance where the flow arrives in sufficient quantity to adequately cover the leaves, so-called effective coverage.

It is defined effective coverage when in a cm2 on the surface of the leaf are present a definite minimum number of drops, also in relation to their average size; this data is called coverage percentage.

To measure the distance to where our machines guarantee an effective coverage, we made some tests in cooperation with the Department of Agricultural Economics and Engineering of two prestigious Italian universities: some supports were positioned one meter from each other, until a distance of 13 meters from the mist blower (the test protocol establishes the sampling at a maximum distance of 13 meters from the point of dispensing) and over each one of them was placed a hydro-sensitive paper (this paper has the property of changing color when in contact with water, showing the distribution obtained).

After the test, thanks to a special computer application, was measured the amount of drops per cm2 in order to calculate the optimum distance.

Here as follow the values obtained:

These values have been obtained with the engine of the mist blower at full throttle (max RPM) and using pure water; using liquids with a different density the values could change.

Obviously the distances reported have been obtained by removing the spreader with the shape of a truncated cone.