Cosmos and a number of other alien plants to South Africa such as blackjack and khakibos arrived in this country during the Boer War. The British imported fodder for their horses from South America and of course this baled grass was full of the seeds of opportunistic plants. The troops carried this fodder in hay nets hanging from their horses and as they rode about the country the seeds were shaken out and took root where ever they fell! With no natural enemies they flourished.
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