The easiest thing to do would be to remove everything above ground now. You'll lose this year's berries, but will get a full crop next year.

If you want to get some berries this year, you could just do that to half of the briar and then do the other half next year.

Once you've done that, in later years you should, in the fall, remove any cane that has fruited but leave all canes that have just emerged. It may be difficult to separate the two in an unsupported wild thorny bramble.

An alternative again would be to manage the bramble by dividing it in 2 halves and get a crop every other year from each. Simply mow one half every 2 years.

The first year after mowing you'll get green canes from the crown. They won't produce that year but if they overwinter they will make berries the following year. Once they fruit you mow the whole thing.

If you haven't already deduced this, blackberries grow in a 2 year cycle. The first year the canes are called primocanes and only produce vegetation. The second year they are called floricanes and they fruit and then die.

If you leave the whole thing unmanaged you will get more and more dead, thorny tangled bramble with a few primocanes winding their way to the light at the top and making fruit.

Murky's suggestions will certainly work and are easiest if you do not wish to tangle too much with thorny canes. Otherwise, if you can tell which canes are the new growth produced last year, and which are dead (having produced berries last year), you can cut out the dead ones and leave the others and they will all produce fruit this year. You'd probably want to use some long-handled loppers to do this. You could then cut back the tops of the remaining canes -- say, to about 5' -- to encourage side branching and thus more berries.

I really like murky's idea of completely removing half of the "patch" one year and the other half the second year...that way you'll always have fruit. It would be pretty hard to get in and just remove the dead floricanes every year, as it's not trellised and is a pretty big, broad patch.

This system is actually quite common (completely removing half of the patch each year) in the machine harvested processing blackberry fields in the PNW. Studies have shown that growers actually get just a tad lower yield over the two year cycle by doing this, but save a ton in labor costs.

Don, I have to disagree a bit here. If they like them, I see no reason to completely remove the patch. If they continue to mow around it, they shouldn't have a problem with it spreading. I do agree that there are blackberries with better flavor (Black Diamond is a fantastic thornless trailing type), but if they're happy with what they've got, then why spend the time and money to rip them out, plant new plants, and construct a trellis?

DH and I removed the Himalayans from a big area of our yard last winter/spring. They had grown down the hill that's behind our house (we don't own the hill itself) and had taken over about half of the backyard, which the previous owners of the house had allowed because they wanted less yard to mow.

Anyway, after we cut them all out and dug up the large roots and crowns, a friend brought his small tractor over and tilled up and smoothed out the area. We then planted grass seed. We still have small blackberries emerging, but with regular mowing it's not a problem, and they won't be able to re-establish and take over the area.

Fruitgirl:

Obviously, I can't tell people what to do in their own yards, but I can tell them what I would do. I wanted to point out that there are better alternatives, and that you do not have to accept a situation like this just because the plants grew in "wild". Not everyone knows there are better blackberry varieties readily available, both in flavor and productivity, without dealing with those very nasty thorns.

My brother lives in the Seattle area, and I have been out with him and his family several times picking Himalayans here and there. A lot of scratches were endured for a scant bucket of berries, while watching out for snakes. By comparison, picking my Triple Crowns and Doyles is a walk in the park.

Don Yellman, Great Falls, VA

When we lived in the PNW we found that the best way to control wild blackberry patches was with a hedge trimmer. Most of the cutting implements we tried (brush cutter, chain saw, machete ) would cut half of the canes diameter and then skid off, leaving the canes falling over but still attached. The hedge trimmer was effective. Suggest you wear rose gloves so that you don't get your hands scratched.
I also like the flavor of the wild blackberries and I also know that getting rid of a patch of them is almost impossible. Perhaps it is possible with chemicals, if you are willing to use them.

OK,

In the interest of disclosure, I have 5 types of blackberries. All are thornless, none are Himalayan, and if I saw those thorny weeds in my yard I'd attack them with a vengeance. The berries can be good though.

I think a lot of the appeal of the "wild" blackberries is that they are free and seem to be from nature. We in the NW get to brag that we have all of this bounty.

I assumed that sinfonian either wanted to stay in harmony with them, or didn't want to endure the effort or perhaps chemicals involved with removing them.

But on second thought, judging from all of the love and work that went into building those beautiful raised beds, I've got to think that she(?) doesn't mind a little effort and is going for the best garden. In that case I think Don's advice is probably pretty good.

Those blackberries are a scourge on a controlled garden. It would be different if it were an open field or the corner of a huge lot.

I just looked at the link...those are in the wetland buffer, right? If they are, I really doubt a trellis or any sort of intensive managment would be allowed, so mowing is probably your only option.

If you want some in your yard, though, to trellis, I'm sure you'd get a lot of advice on varieties and such.

OK, now I actually read some of the blog too. Sorry for the gender mix-up sinfonian.

I'm back to my first recommendation of "mowing" in halves.

I'd also recommend removing the grass for at least a few feet diameter around the apple tree and mulching it.

No surprise that your $150 or so worth of split firewood went quickly if you offered it up for free on Craig's list.

I'm mulling the idea of trying some of those potato bins. I'd thought of making them out of cedar, but that would be about $80 apiece. I guess I'll see if they have cheap pine at Home Depot or Lowes.

Wow, what an amazing response. I REALLY appreciate everyone's comments. I don't think anyone was trying to force me one way or another. I appreciate all advice from experts such as yourselves.

First off, sorry I didn't respond sooner. My work interent connection blocks gardenweb, so I was stuck reading my email and wishing I could respond. Now I'm glad I waited since many of the things I was going to clarify came out in later posts after reading my blog. Thanks again for doing so, I am proud of my first blog as well as my first attempt at gardening. I'm glad it cleared up my situation.

Frankly as little invasion I can do the better off I'll be. It's not really a wetland per-se, but it isn't my land either (so no chemicals even if I'm not above them if they're the best alternative). The blackberries just THINK my yard is an extension of their territory. That and the only person that can possibly get to that spot is my neighbor and we both kinda share the harvest. So anything I do will need to be decided with him, but he's a great neighbor. Expecially if I do the work since he's going on 80.

After reading all the posts on email. I am partial to the partial pruning one year and harvesting the remainder, then repeating the next. However, I think I'll likely devistate (rather than prune) the middle swath so I can harvest the middle easier by walking down the path. Kinda like trellising without the supports.

So I assume pruning will be just hacking them to the ground level, and the crown will sprout from under the ground?

Secondly, when is the best time to prune these? Would it by chance be right after the growing season's over (fallish) so we can still harvest what we can? Or is it spring or summer or winter?
Eventually I'd like to have it so it's as managable as nature will allow. I know just how invasive they are, but as I've never tasted any other blackberries (that I recall), they taste great to me, and make great jams and baked goods. If I had room I'd plant some nice thornless ones but I'm all tapped out.

Lastly, no problem on my gender, my avatar or whatever's gender neutral even if a Sinfonian's a member of a professional "men's" music fraternity. hehe. And I appreciate the information about my Himalayan weeds and all the amazing hybrids out there without thorns. I wish I could replant out there. Not going to happen. Others will get tons of great info from this post. Thank you all very much!

Sinfonian

Here is a link that might be useful: Sinfonian's blog

I'd also get rid of the ivy, another bane here that has gobbled up acres of urban land. Garden centers and mailorder houses have other varieties of blackberries with more desirable characteristics. The big weedy one started out as a cultivar 'Himalayan Giant' (and which is still grown under that name in UK) that went wild. The seeds were obtained by Luther Burbank from the Himalayan region but the parent species is actually Rubus armeniacus.

No poisonous snakes in Seattle area, if that was the reason for watching for snakes while picking berries.

Bboy, you know, I actually noticed the ivy when we took the picture. I had never noticed it before. I don't have ivy in my yard, though I did clear out about 50 pounds of morning glories from my raised bed garden area before I built my beds over landscape fabric and gravel. I will definitely pull the ivy out. I won't worry about the morning glories, there's no way I'd rid myself of them in that overgrown area. I just have to fight the good fight every year to keep the woods out of my back yard. And you're right about the snakes, all we have is gardner snakes, which are very cute.

Here is a link that might be useful: Sinfonian's garden adventure

Knowledgeable folks:

When is the best time to prune these back? After harvesting (hopefully), or winter?

Thanks!

Sinfonian

Here is a link that might be useful: Sinfonian's garden adventure

Cut root suckers as they appear. Remove fruiting canes after harvest. Weave new canes around top wire in fall or leave on ground until spring to reduce winter injury

Here is a link that might be useful: Blackberries

You can prune blackberries back anytime after harvesting (September is usually the end of this) until March in the Seattle area. Waiting much longer than this risks destroying the new protocanes sprouting up.

On a wild patch like this, height control will make harvesting easier. Cut the new protocanes when they get around head-height. This usually happens by Fourth of July. That will encourage side-branching. If there is no time for this, break out the stepladders.

The flavor of these wild blackberries is variable, but if you are lucky, certain patches bear fruit to die for.

If all this reduction, pruning, and topping reduces your harvest too much, toss some manure/compost around the remaining clumps in the winter. This only needs to be done every few years.

Watering can help the fruit if June and July are unusually hot and dry.

"Gardener" snakes are more commonly referred to as garter snakes. They have to be pretty harmless to be used as garters.

Anyone (jellyman) recommending putting poisons on your landscape should be ignored or sentenced to a thorny grave. Roundup or 2-4-D are toxic not only to plants but all living things. The soil is an ecosystem of microbiota and fungi which release and transmit nutrient to plants. Roundup kills the beneficial bacteria in the soil and lasts for years, enters the food of Roundup Ready crops and as can kill the beneficial human gut bacteria, and cause leaky gut syndrome, Why poison your own land? If you want eradicate invasive plants and thorny plants, you can mow them down, dig them up and cover the soil with cardboard and mulch, or old carpets for a year. I suggest planting the thornless blackberry which is so much easier to harvest and manage.