If you own land in Oregon, you have probably fought blackberries. You cut them back in the spring, and by late summer they are taller than you are. Clear a patch completely, and two years later it looks like you never touched it. Blackberries are not just stubborn. They are built to come back, and getting rid of them for good means understanding how they spread.
Why are blackberries so hard to get rid of in Oregon?
Most of the blackberry growing wild across Western Oregon is Himalayan blackberry, a non-native, invasive plant. It thrives in our mild, wet climate and spreads in several ways at once:
- Root crowns. Each plant grows from a woody crown just below the surface. Cut the canes off at ground level and the crown simply sends up new ones.
- Tip rooting. When a long cane arches over and touches the ground, the tip can take root and start a brand new plant. That is how a single bush turns into a thicket.
- Seeds. Birds and other animals eat the berries and spread the seeds across your property and your neighbors’.
- Root fragments. Pieces of root left in the soil can resprout.
Because of all this, mowing or cutting alone almost never removes blackberries. It sets them back for a season, and the established roots come back stronger.
What actually works to remove blackberries for good?
Lasting removal comes from a combination of three steps, not any single one.
- Cut back the canes. Clearing the top growth with a mower, brush cutter or machine opens the area up so you can see and reach the root crowns.
- Remove the root crowns. This is the step most people skip. Digging or pulling out the crowns removes the source of the regrowth. On larger areas, equipment can grub out crowns far faster than hand tools.
- Follow up. Even after a thorough job, seeds and small root pieces will sprout. Pulling or cutting those small shoots over the next one to two growing seasons, before they get established, is what finishes the job.
Some people also use herbicide on regrowth. If you go that route, follow the product label exactly and check any local guidance, especially near streams, wells, gardens or livestock.
What should you do with the cleared canes?
Do not leave cut canes and root crowns lying on the ground. Canes can root where they touch the soil, and crowns left on the surface can resprout. Common options are hauling the material off, chipping or mulching it, or burning it where conditions and local rules allow. If you are in a burn area, check burn day rules and permits first.
How do you keep blackberries from coming back?
- Plant or maintain the cleared ground. Bare soil is an open invitation. Grass, pasture, ground cover or regular mowing makes it much harder for new blackberries to get started.
- Mow or graze regularly. Young shoots are easy to knock down before they get woody. Goats and other grazing animals can help keep regrowth in check.
- Watch fence lines and edges. Blackberries often creep back in from a neighboring property or a ditch line. Catching them early is far easier than clearing a new thicket.
- Check once or twice a year. A quick walk in spring and late summer to pull small shoots keeps a cleared area clear.
When is the best time to clear blackberries?
Blackberries can be cut back any time of year, but each season has tradeoffs:
| Season | Pros | Cons |
|---|---|---|
| Fall and winter | Less leaf growth, easier to see crowns and ground | Wet ground can be soft for equipment |
| Spring | Ground is often workable, regrowth can be caught early | Plants are actively growing |
| Summer | Dry, firm ground for equipment | Thickest growth, more material to handle; fire caution in dry spells |
For root crown removal with equipment, firm ground matters most, so late spring through early fall is usually easiest. Follow-up pulling of small shoots is best done in spring and summer when they are easy to spot.
Is it worth doing yourself?
Small patches can be handled with loppers, heavy gloves, a mattock and patience. Large thickets, steep slopes, overgrown fence lines and acreage are a different story. Equipment such as a tracked skid steer with a brush cutter or grapple, or an excavator, can clear and grub out crowns in hours instead of weeks, and leaves the ground ready for whatever comes next.
Frequently asked questions
No. Mowing cuts the canes but leaves the root crowns in the ground, so the plants grow back. Regular mowing can keep young regrowth from getting established after the crowns have been removed.
Expect to follow up for one to two growing seasons after the main clearing. Seeds and small root pieces will sprout, and removing them while they are small is what keeps the area clear.
In many rural areas you can, but it depends on where you live and the time of year. Check your local fire district for burn day rules and any permits before burning.
Covering small areas with heavy material for a long time can weaken them, but on larger patches it rarely works on its own. Removing the root crowns is the most reliable method.
Learn more about how we approach brush and land clearing on rural property.