London Metropolitian Police publish updated list of anti-personnel plants

Creeping Juniper, Blue Spruce, Common Holly, Giant Rhubarb, Golden Bamboo, Chinese Jujube, Firethorn Pyracantha 'Orange Glow', Shrub Rose, Pencil Christmas Tree, Juniper, Purple Berberis, Mountain Pine, Blue Pine, Oleaster, Blackthorn, Fuschia-flowered Gooseberry, Prickly ash (Zanthoxylum).  In addition, the following thorny plants can also be considered:: Aralia, Chaenomeles, Colletia, Crataegus (including hawthorn/may), Hippophae (sea buckthorn), Maclura, Mahonia, Oplopanax, Osmanthus, Poncirus, Rhamnus, Rosa (climbing & shrub roses), Rubus (bramble), Smilax

http://www.met.police.uk/crimeprevention/garden.htm