Remove giant hogweed, Hercules shrub – report and fight

The control of the Hercules perennial must be carried out consistently and consistently over several years. Just a few forgotten seed heads are enough for the plant to expand explosively. It is best to fight from the outside in. So you start with the smaller stands outside the center and work your way to the core of the plants. It takes about three to four years before the population is wiped out.

Damage from the Herkulesstaude

One often reads sensational articles about the Hercules shrub in the press. Scare tactics are not really necessary. It is important to know that it is better not to touch the plant. It can actually cause considerable damage to health. Mere touch can have bad effects. However, there are other problems of a very different nature that I would like to briefly address.

• Health damage
• Visibility restrictions in traffic, solely due to the height of the plants at the roadside
• Increased risk of erosion at the edge of rivers
• Risk of erosion also on slopes of ravines
• If the plant spreads on agricultural land, it is absolutely serious competition for crops
• Small range of species due to the shading of the large plants
• Threatened rare plants

Health risks

A simple contact with the leaves of the giant hogweed is enough for the skin to show reddening, skin inflammation, irritation and, in severe cases, meadow grass dermatitis (inflammatory, painful blistering). This goes up to extensive first and second degree burns. Weeping wounds that last for weeks can develop, sometimes with persistent pigment changes. Fever, sweats and circulatory shock are also common.

Often this does not happen at first, but only days later, when the skin has come into contact with sunlight. But then it can get really bad, up to and including acute bronchitis.

In some cases it has also happened that people who did not touch the plant directly, but only stayed near it, exhibited the above-mentioned symptoms and shortness of breath. That was mostly the case on particularly hot days.

If you have had contact with the hogweed plant, the affected skin areas should be cleaned with soap and water. It is essential to avoid sunlight. To be on the safe side, a doctor should be consulted, even if there are no symptoms.

Recognize the hogweed

The giant hogweed is a biennial or perennial herbaceous plant that can grow three to four meters high. It reaches this level within a few weeks. The stem can reach a diameter of up to 10 cm at the base. Numerous large dark or wine-red spots on its surface are typical. The leaves can also take on considerable proportions. Leaves about one meter long are normal, but under favorable conditions they can grow up to three meters long (including the petiole). The leaves are divided into three, five or nine pinnate sections.
The inflorescences are also remarkable. They reach a diameter of 30 to 50 cm. A single umbel can contain up to 80,000 individual flowers and produce up to 30,000 seeds. The flower color is white. The flowering period extends from June to July.
After flowering, the plant dies. Only bear claw plants that do not flower can survive. If the plants perish after the season, it is not a tragedy, because they have provided enough replenishment. The seeds survive in the soil for years.

They always germinate early in the year, often as early as mid-February. Since the young plants grow rapidly and vigorously, they deprive competing plants of the basis of nutrition and light. At the beginning of May they can be three feet high. Native plants often no longer stand a chance. The large leaves provide shade on the ground and block the growth of other plants.

Report hogweed populations?

If you discover a bear’s claw plant in the garden, you as the owner are responsible for removing it. Nothing needs to be reported. There are also garden owners who cultivate individual plants, as a bee pasture or something similar. It is not mandatory to report naturally occurring stocks to any authority, but it is certainly useful so that no one can injure themselves on the plants. You turn to the responsible regulatory office, the environmental office, the municipality or city administration or the lower nature conservation authority, always in the hope of finding a competent contact person.

Fighting the giant hogweed

Anyone who thinks they can control hogweed by mowing is wrong. Unfortunately it’s not that easy. The hogweed stores its strength in a beet-like thickening at the base of the shoot and in the upper parts of the root. This allows the plant to sprout early in the year and several times. The hogweed usually does flower and can reproduce. Even if the root of the plant dies after flowering, there are plenty of new ones.

A distinction is made between the control methods according to the infected areas. In the home garden, the action is different than in the case of a large population of hogweed. It is important to start as early as possible in the year when the plants are still low and “tender”. You should start in April at the latest. In the following year there must be follow-up checks or repetitions of the actions.

No matter where and how you fight hogweed, protective clothing is important. This also includes protective goggles and, if necessary, respiratory protection. In the case of high stocks, the use of a pruning saw with a handle is recommended. In this way, injuries from the nettle hairs can be avoided. In addition, you should not work in sunshine, but only when the sky is overcast.

Combat in the home garden

Unfortunately, cutting off the plants is not enough. Even repeated mowing does not lead to death. It is more likely to form small inflorescences, a so-called emergency flower. Mowing or cutting off slows down the spread of the plant, but does not prevent it.

• The whole plant must be dug up.
• The best time for this is early spring and spring.
• Alternatively, cut off the root 15 cm below the surface of the earth. The plant can no longer sprout from the remaining roots. The lower part of the root will rot in the ground. This measure makes sense during the entire growing season. However, the smaller the plants, the easier this method is. The possibility of skin contact is then also less.
• Caution: when chopping, sap can splash away!
• Regular follow-up checks and, if necessary, remove any drifting plants, including the roots
• Since the hogweed needs sun to thrive, you will harm it if you withdraw it. The easiest way to do this is to cover the surfaces with black, opaque fleece or tarpaulin.
• The plants also do not like acidic soil. If the soil is acidified, seeds and seedlings have no chance of developing into normal plants.
• If the hogweed has not been controlled in the spring, it is necessary to remove the inflorescences or seed heads. This fight is associated with health risks
• The seeds must be prevented from falling out. This can also be done by packing the entire inflorescence of individual plants, for example in a sealed plastic bag. The plant dies and can be disposed of with the bag and seeds.
• Pesticides are not permitted for the control of hogweed in the home garden.

Combat large areas

• Multiple mowing and mulching, milling and grazing with cows, sheep and goats
• Plant protection products may only be used if proof of competence has been provided and a special permit issued by the nature conservation authority.
• Herbicides are used that have a systemic effect. The active ingredient is absorbed through the leaves and transported to the roots. The whole plant dies.
• Medium with the active ingredient triclopyr are particularly suitable. The advantage of the remedy is that it only works on dicotyledonous plants, not on grasses. An intact sward is important to suppress the germination of the hogweed seeds.
• Repeated milling and plowing at least 15 cm deep, destroys newly emerging seedlings.
• Then grasses that grow quickly should be sown. They take the seeds of the Hercules plant light for germination.

Conclusion
The Hercules shrub is dangerous. Especially those who have children should not accept compromises. The perennial must disappear from the garden. Only continuous control will help to permanently eradicate the plant. It is important to protect yourself, your whole body and preferably your airways. It is safest to tear the whole plant out of the ground or to cut the root at an angle of 10 to 15 cm. You have to check once a month whether new shoots have taken place or whether seedlings have sprouted. If so, they must also be removed. This check must be carried out every month. You have to stay on the ball in the years to come. The seeds can survive in the soil for a long time. Everything has to be removed. Irregular mowing, chopping off and cutting off flowers are unsuitable control measures. The hogweed can also be encountered on a walk through nature. Then it is important to keep children and dogs away. The best thing is that nobody comes into contact with the plant in any way.