Euston-Brown, D., Rathogwa, N & Richardson ... - DWA Home Page

disturbance of the soil will probably also stimulate the indigenous seed pool to germinate. If follow
up with control burn is planned, then an initial clearing that enhances germination and establishment
of alien seeds in the soil should be done beforehand. This approach should reduce the load of
germinable seed in the soil, especially for weeds with longer-lived seed. It may also help to reverse bush
encroachment.
A major advantage of hand pulling is that it negates the need for herbicides. It is thus most appropriate
in sensitive areas with high conservation importance or on the edge of wetlands or rivers, where
herbicide could affect invertebrates and fish. It is an ideal method for low-density infestations in the
second or third follow up situations after the bulk of the clearing has already been done. It is also
useful to integrate herbicidal control with hand pulling. With both these weeds, and others, one often
finds a core infestation with lighter infestations around it. It is most effective for one or two people to
hand pull the scattered individuals while herbicidal treatments are applied to the denser areas where
hand pulling is too labour intensive.
Treatment Advantages (Benefits) Disadvantages (Limitations)
Hand pulling • Selective
• Minimises risk to native plants
• Easily integrated with other methods
• Effective in light infestations
• Develops plant identification skills and understanding of
plant biology
• disturbance may enhance establishment of native plants,
especially grasses
• minimal equipment or protective clothing required – saves time.
• no herbicide cost
4.3.1.2b) Slashing
Handpulling
• Disturbance of soil can enhance weed
establishment
• Limited to wet periods when soil is moist
• Limited to light (low to medium density) infestations
< 1m tall
• Risk: stems that break above the roots grow back
• Labour intensive
• Risk: need to ensure that roots not in contact with
soil or they can sprout under favourable conditions
• Worker fatigue and back pain – reduced work rate
Slashing is generally done with a panga or sharp blade at the end of an arm-length stick or short
handle. This method may be appropriate when integrated with an appropriately timed follow up to
deal with coppice. The aim here is to stress weeds or to prevent them from flowering and producing
seed, and giving the native plants a competitive edge. With both chromolaena and lantana, slashing
only also stimulates vigorous fresh growth (after enough rain). This new growth may be more
responsive to herbicide treatments, and the site is also easier to access and is more quickly covered
after being slashed. For chromolaena the most appropriate time to use this method is just before or as
Development of a clearing protocol based on ecological criteria for Mesic Savannas and Sweet Grassveld for the Working for Water Programme
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