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

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plots was cleared in 2004). This meant that cleared plots were seeded by the surrounding chromolaena.
There was also no overall significant decrease in chromolaena density between the different years
at Hilltop, and the higher rainfall in 2006 also resulted in an abundance of new seedlings (see
Figure 7 below). Further, It was found in 2006 that the sites where stacking was done had more
chromolaena seedlings and a higher cover of chromolaena than sites where no stacking was done. This
might suggest than mulching by spreading cut chromolaena on the ground might be a useful way of
limiting seedling recruitment. The stacked plots also took longer to clear in 2006 because of the higher
number and cover of chromolaena and lantana plants that had emerged. (see Figure 6 below).
Figure 6: Hilltop site. Person days per ha to apply initial clearing treatments in 2004 and follow up treatment
in 2006.
In 2004 the Hilltop sites took an average of 55 person days per ha to clear while in 2005 they took
an average of 9 days per ha, which is about six times less. There was a significant average increase
in grass diversity at the hilltop site between 2004 and 2006 (T-test p=0.005). The average % cover
chromolaena in 2005 (35 %) was significantly less than its average cover in 2004 (74 %) (p=0.001).
Figure 7: Hilltop site: the change in chromolaena density across all plots in 2004, 2005 and 2006.
Appendix 2