Rubus armeniacus (Himalayan blackberry)

R. armeniacus tends to invade disturbed sites such that protecting native species and the dense planting of shade producing shrubs or trees can provide control (Soll, 2004; Bugwood wiki, 2015).

A range of physical control methods focused on mechanical removal of both the vegetation and roots are available. These include hand pulling, hand hoeing, cutting, burning, goat grazing, digging and removal with machines such as disking or ploughing. Each method has reported advantages and disadvantages and several methods are often used in combination. For example, hand pulling is most suitable when the plants are in seedling stage. Cutting and burning both effectively remove the above ground part of the plant but must be repeated multiple times over a number of years because the root crown will continue to re-sprout. Burning does not prevent re-sprouting from the root crowns either and has been reported to provide good conditions for seedling germination (Ensley, 2015). However, in wetlands, cutting to ground level has proven effective as without the supporting canes, roots are reportedly unable to survive in anaerobic conditions (Soll, 2004). Similarly disking or ploughing should be repeated and care taken that the rhizomes are not spread further. Digging is labour intensive, but when thoroughly undertaken, i.e. removing all large root fragments, is an effective method for removal and is a suitable follow up to cutting (Soll, 2004; Stannard, 2014). A recent study from the Pacific Northwest of the USA, compared the effectiveness of high intensity, short duration goat grazing with mowing and goat grazing followed by mowing. Each treatment caused the species to decline but there was not a significant difference between the three treatments (Ingham, 2014).

The rust fungus, Phragmidium violaceum, recently discovered on R. armeniacus in North America has triggered research into its potential as a biological control agent. Specific strains of the rust have been used to control other invasive Rubus species in Chile, Australia and New Zealand (Peters, 2012).

Due to the variable regulations around (de-)registration of pesticides, we are for the moment not including any specific chemical control recommendations. For further information, we recommend you visit the following resources: