At Arbor-care we are constantly assessing how we can introduce smarter, more effective working methods to make our clients’ lives easier. The introduction of a tractor-drawn flail to clear plantations of weeds is a prime example.

In forestry the area between rows of trees, commonly referred to as the interrow, should be kept relatively free of weeds to allow for easy access into the plantation, reduce incendiary material for fires and reduce competition between the weeds and the trees for water, nutrients and light. This clearing is traditionally done either by manually slashing down the weeds or treating the weeds with herbicides applied with knapsack sprayers. Both methods are labour intensive and time-consuming and in a move to modernise and reduce costs we decided to investigate more mechanical alternatives.

We first tried clearing the interrow with a tractor-drawn disc harrow and in some areas this proved to be reasonably successful. However, where there are old tree stumps in the interrow, the discs are easily damaged which results in downtime and additional costs. Another concern is that the surface capillary roots of the young trees are cut by the discs while clearing and the effect of this on tree growth is still to be determined.

Before and after: the flail clears quickly and effectively

without causing damage to the roots of the young trees.

We then came up with an innovative mechanical alternative: a tractor-drawn flail. The flail comprises a hydraulically driven horizontal shaft to which heavy duty chains are fitted, encased in a housing that prevents flailed debris from flying out and causing damage. The spinning chains are set to just brush the surface of the soil and remove the weeds with very limited disturbance of the surface. The flail can pass over stumps up to 300mm in height and also doesn’t harm the capillary roots. In addition, the flail mulches any dry branches and other organic material on the interrow, returning nutrients to the soil.  

This clearing method has proved to be so successful that Thuthugani Contractors currently has three flails working in Northern KZN.

The flail at work