The invasive giant taking over your raspberry patch

With its beautiful bright pink appearance, Himalayan balsam may not seem particularly threatening, but it is an invader that has no place in our natural environment. Originally from the western Himalayas, the plant has taken root and flourished in Sweden and elsewhere, becoming a major threat to biodiversity.

To halt its spread, remove giant balsam before it seeds, says Linda Backlund.

To halt its spread, remove giant balsam before it seeds, says Linda Backlund.

Foto: Abebe Asres

Västerbotten2023-08-16 14:03

Invasive species, such as Himalayan balsam, are animals, plants or fungi that have been introduced to Sweden by humans. Their rapid growth can crowd out native plants, including raspberry bushes. This has led to their inclusion on the EU's list of invasive alien species.

Linda Backlund, invasive species coordinator for the Umeå, has been busy this spring and summer sending out information sheets to property owners who have these alien species on their land. The owners are obliged to remove them, especially if they are EU-listed invasive alien species, and can be fined if they fail to do so.

Even though the plant is beautifully bright light pink and may not look particularly dangerous to the eye, giant balsam does not belong in Norrland nature.

– Most people have no idea they have an invasive plant on their property. Our outreach has had an impact and many are now aware that they must remove Himalayan balsam, for example. We have not fined anyone this year, Backlund told VK.

Linda Backlund emphasizes the importance of reporting findings on the website in order to know where invasive plants need to be controlled.

The plant secretes a toxin (which is not harmful to humans) that hinders other seeds in the ground from thriving, thus preventing native plants from growing. If the Himalayan balsam is not removed, it will gradually take over entirely.

– We have heard from several people that their raspberry patches have disappeared due to invasive species. We are simply losing our raspberry patches, says Backlund.

It's an invasive species that supplants for example, raspberry bushes, says Linda Backlund, coordinator for invasive species at the County Administrative Board (Länsstyrelse), Umeå.

Himalayan balsam is not only a problem for other plants, but also for pollinating insects. A classic Swedish summer meadow blooms from June, while Himalayan balsam blooms from mid-July. According to Backlund, this creates problems for insects, as there is nothing for them to eat from June to mid-July, so they can't survive.

To prevent the plant from spreading further, it needs to be burned rather than composted.

– Not everyone knows that the plant should not be composted, but burned to prevent it from spreading further, says Backlund.

Giant balsam has taken over a large area of a meadow in Umeå and can grow up to three meters high.

With only two weeks left before the plant starts to seed, those who have not yet begun to eradicate Himalayan balsam should do so as a matter of urgency, or it will come back even stronger.

– It's high time to pull them up now before they start to seed. Then it's vital that people report it if they see an invasive plant, says Backlund.

In the background you can see how a giant balsam plant creeps closer to the ripe raspberries.

Invasive plants

Invasive plants in Västerbotten:

Himalayan balsam
Giant hogweed
Persian hogweed
Himalayan knotweed
Large-leaved lupine
Nootka lupine
Rugosa rose
Common blue-sow-thistle
Canadian goldenrod

Source: Länsstyrelsen


Dispose of carefully:

• Take plant waste to your recycling center for incineration.

• Smaller amounts of waste can also be placed in household trash, securely sealed in a plastic bag.

• During transport, the waste must be well-sealed.

• If the waste is taken to a recycling center, ensure that it is burned and not composted. Check with the on-site staff for local regulations.

Source: Länsstyrelsen