Weed of the Week: Himalayan Blackberry (Rubus armeniacus)
Before we start on this weeks weed; Himalayan Blackberry, let’s discuss what a noxious weed is. A noxious weed is a non-native plant (typically) that can have a determination effect on the environment. Typically that effect starts with pushing out native plants. Removing native plants and replacing them with non-natives will effect other plants, insects, birds, amphibians, and up the food chain to mammals. Noxious weeds have many ways of taking habitat away from native plants, some release chemicals, some produce 1000’s of seeds that survive 10+ years in the soil, some physically overtake native plants and trees. In this week’s case, Blackberry typically crowds out native plant, stealing their light and water.
Today we will discuss Himalayan Blackberry, a delicious but very destructive noxious weed. While I can’t think of a better summer treat then a slice of warm blackberry pie, the vines where they come from are savage and fierce. Anyone who has tried to eradicate them knows they are a pain in the ass, quite literally! But clearing your property can be very beneficial. The vines can climb smoother huge trees, killing large deciduous and conifer trees. They can over take your property in a matter of a few years if not controlled. The delicious fruits are a food source for many birds and mammals, this is the way their seeds are distributed to new areas.
The Himalayan Blackberry can survive in full sun to part shade, in dry to moist soil. They cannot live in full shade or in saturated soil, this is why a common control method in environmental restoration is to increase tree canopy to shade out the plants. If you have plants on your property planting trees to increase canopy is a great longterm control method, but in the short term you may need to rely on chemicals. Spraying with approved herbicide, waiting until the plants die and then mechanical removal (weed whacker, mowing, disking) is typically very successful, but many require follow up treatments for a couple years.
As with any large invasive, removing them and leaving bare ground makes room for either the same plant to return or a new invasive to move in. ALWAYS have a plan on how you will keep them for returning to your new bare soil. Installing new vegetation, reapplication of herbicide, mechanical removal as soon as new sprouts begin or other options will work.
There are many more species of Blackberries beside Himalayan, some are native to parts of the US and some are not.
- Trailing Blackberry (Rubus ursinus): Native to the Pacific Northwest
- Sawtooth blackberry or tall blackberry (Rubus argutus): Native to eastern and south-central United States
- Elmleaf blackberry or Thornless blackberry (Rubus ulmifolius): Native to Europe and North Africa, now found on the westcost of the US
- Evergreen Blackberry (Rubus laciniatus): Native to northern and central Europe, now an invasive plant in the US, primarily the Pacific Northwest
Blackberry is difficult and costly to control, I highly recommend not waiting and start now! If you find even one vine starting in your yard remove it as soon as possible. It can get out of hand in a short amount of time. Contract your local weed board for recommendation on specific ways to control this invasive plant in your area.
Since I’m posting this in August, the month when blackberries are typically ripe and ready to pick, go ahead and pick some berries*. Make something delicious, because if you can’t beat them, eat them! While you enjoy your delicious treat contemplate how you will destroy them.
*Check to be sure the plants you pick from have not been sprayed with herbicide before picking any berries