Once Jacobaea vulgaris has settled in a horse meadow, it is often difficult to fight the plant. Jacobaea vulgaris grows fast and has few natural enemies.
To prevent poisoning of your horse, it is important to fight Jacobaea vulgaris : directly when the plant is present. Instant combat also prevents the seeds from spreading. It is very important that the plant does not bloom because the seeds that arise there are years of germination and blow meters far away.
Chemical (Local to plant level)
Chemical control of Jacobaea vulgaris is possible. For this, 2.4 D or MCPA is often used, but such a device does not match a large plant. Glyphophate, the active ingredient of Round-up, is also effective against Jacobaea vulgaris .
Because Jacobaea vulgaris has strong developed roots, it takes a lot of time for grown plants before the pesticide has reached the core of the roots and can do their work. Chemical fighting will have a better effect if the plants are still very young (in spring). In chemical control, pay attention to the small rosettes that otherwise grow into blooming plants.
Pesticides best fight when the plant grows. Therefore, it is advisable to use pesticides at dry or extremely high or low temperatures. Under these conditions, the plant grows a lot slower and reduces the amount of the agent.
However, dead-sprouts of Jacobaea vulgaris crops must still be removed because they are life-threatening to animals and humans.
Biological pest control
Besides chemical fighting, it is also possible to combat Jacobaea vulgaris in a biological way. More than 120 insects and lower organisms depend on Jacobaea vulgaris as food. Jacobsweed is not toxic to these organisms.
In the 1980s, a combined deployment of moth and beetle in Oregon caused the vegetation to reduce Jacobaea vulgaris by more than 90 percent. Good results have also been achieved in New Zealand. Within a few years there was a reduction of more than 90 percent of the plant locally.
Biological control, however, is a long-term project (longer than 10 years) in connection with the population population of insects.
In the Netherlands there is no experience with biological control of Jacobaea vulgaris.
Biological combatants are:
- Beetles (Longitarsus species)
- Moths (caterpillars) such as the Tyria Jacobaeae, Cochylis atricopitana and Platyptilia isodactylus
- Flies (Botanophila seneciella)
The Saint Jacob’s Butterfly (Tyria Jacobaeae), which originates from the Zebrarups, eats the leaves and Stalks of Jacobaea vulgaris , but the main reserves are in the rootstock, which causes the plant to recover. The caterpillars eat the above-ground, green parts of the plant and can cause proper damage to the plant.
Another natural enemy of Jacobaea vulgaris is the rabbit. Rabbits enjoy rosemary roots and do not experience adverse effects of the toxins. The rabbit population, however, has been decreased, which increased the growth of Jacobaea vulgaris.
Manual removal
The manual removal of Jacobaea vulgaris is a fairly effective method, mainly in areas where Jacobaea vulgaris crops are found in small coverings.
Importantly, the plants are rooted with the whole root, most preferably before Jacobaea vulgaris sprouts blossom in May / June. If you are going to manually remove Jacobaea vulgaris , it is wise to wear gloves.
If Jacobaea vulgaris is not completely pulled out of the soil, new plants can be found from residual root remains. Manual deletion is therefore only effective in seedlings and rosettes. Because the root system is not yet developed, all roots can be removed more easily.
Store drawn plants in tight bags, buckets or burn them. Blooming plants even put seeds when they are rooted and already stretched out. Check the cleaned spots regularly on new rosettes.
Mowing
Mowing is not suitable for fighting Jacobaea vulgaris. The plants react by forming new flower buds in a short period of time and producing additional seeds. Very frequent mowing also leads to vegetative spread and plants with a strong woody root.
Fighting Jacobaea vulgaris is therefore not easy. Often the methods described above will not be sufficient. In such cases, plowing and re-sowing can be a solution.