Do a web search for "Rubus ursinus". The native are quite different, ropey and creeping on the ground except where supported by a shrub, boulder or fence. All blackberries with tall, self-supporting, thick and stiff canes are exotic weed species. The Himalayan blackberry (R. armeniacus) and evergreen blackberry (R. lacinatus) are the locally prevalent ones.

The native blackberries have thin floppy stems, about a quarter inch in diameter; the non-natives have very thick strong stems, easily at least half an inch in diameter. The native thorns are hairy splintery things, whereas the non-natives have ones more like rose thorns. The natives are done flowering and are nearly ripe now; while the non-natives are blooming with a few green berries.

Hope that helps!

Wear leather gloves, sturdy jeans and long sleeves to deal with these plants. When you get caught on the thorns move toward it's roots to get off of them.

I like to use a fork to dig the roots, it lets me loosen all around them rather than trying to go through them.

Himalayan and native also cross to produce Cascade berry. Himalayan actually European in origin, L. Burbank got seeds from cultivated(?) plants in Himalayan region and named one seedling 'Himalayan Giant'. Thousands of unwanted progeny later we call it Himalayan blackberry. ('Himalayan Giant' still listed and sold in UK).

I have also heard that you want to let the vines dry out thoroughly before you put them in the compost, or any vine with any life left in it will re-sprout. They are pretty tenacious beasts. I drape the vines over my woodpile so no part touches the ground, and let them dry out for several months before they go through the chipper-shredder and into the compost heap.

I used to have a Samoyed (white husky) dog that loved to eat blackberries. I had to rescue him many times with loppers as he was totally imobilied with the thorns. Funny though..

This thread is so timely for me since we too just moved to the area. Our entire backyard was covered with blackberries. We had a small excavator rip out about an acre of them. I have been going out every few days to dig where they have sprouted up again. A landscape designer neighbor told me to fence the yard and get a couple of pigs to take care of the rerooting problem:) I am hesitant to use herbicides since we do host a lot of wildlife.

Goats are most effective for vegetation control. Do not root around and muddy the soil, either, nor do they emit pig manure with its distinctive bouquet.

We never seem to get rid of them. It is a perpetual battle, but we are getting philosophical about them and look at them as a free source of mulch after all the cutting, chipping, and digging tiny thorns out of my fingers. Mowing seems to be the easiest control for us, but they pop up in our borders and woods. I don't want to spray but have painted the cut surface with weed killer and it sets them back for a while at least. Digging out the roots is good if you can get them all.

My personal favorite for berries is the evergreen blackberry. It has better flavor than the Himalayan, is easier to control since the canes are not so long, and the native R. ursinus is not very productive, the berries are very small, and mold quickly. I once got sick after eating some slightly moldy ones.

I'm growing some thornless blackberries and will actually get a good crop this year so will report on how I like them.

You can rent goats temporarily to clear your property of blackberries. They are that effective that people actually keep herds and rent them. A friend of mine just did this in Mollala.

Just remember that goats will eat most everything they have access to, including native plants or ornamentals you may be trying to retain. They act as browse-down mowers, and invasives often will resprout nicely after being eaten back, outcompeting slower growing desirable species.