What is the problem with Himalayan blackberry?

Himalayan blackberry is an aggressive alien plant that was introduced to the Pacific Northwest a little over a hundred years ago but has moved in and displaced many native species.It grows at a phenominal rate,up to 20 feet in one season. Along stream banks,it crowds out species that would normally set roots and control erosian. It does not set roots that effectively hold the soil together.In logged or burned over forests it stifles the restoration of desired native species by moving in almost immediately after the disturbance.Left to its own it will totally take over pastures,croplands and vacant lots.It climbs over fences, buildings,paths and roads. It is almost impossible to control as the least rootlet will produce a plant if one attemps to dig it out. There are chemical applications that can control it but they must be reapplied again and again.The fruit is delicious but never in short supply,which brings up one of the major ways it is spread far and wide, birds. Think of it as kudzu with viscious thorns and tastey berries.