How To Get Rid of Bull Thistle

By Subodh / January 13, 2014

So what is bull thistle after all? Bull thistle is a large flowering plant that comes in the sunflower family and is biennial. It is widely found in Europe, Western Asia, Australia and now even North America. Its scientific name is Cirsuim vulgare. In fact, bull thistle is one type of Cirsuim vulgare. Bull thistle can grow up to 5 feet long and they typically have a pink or purple crown shaped flower on the top. It can be typically identified by its spiny, lobed leaves with a crown shaped flower on top of each stem. While honeybees and butterflies love them, it can be quite annoying to have them in your garden as they take away the nutrients and compete with other vegetation and plants that you might have grown.

Bull thistle mostly grows in vacant lands and vacant gardens, as they do not require much nutrients and water to survive. Since they are highly competitive plants, they can become a nuisance to you as they take away the nutrients from the soil making it ineffective for any other plant or herbs. They usually grow in hay fields and pasture. There are many ways to get rid off them but the tricky part about these plants is the seeds. The seeds of these biennial plants can survive up to one year and if they go beneath the soil then they can remain dormant for up to three years before growing again. Therefore, you might have to use more than one of the solutions in combination to get rid off them completely. Here are five ways to get rid of these weeds.

Bull Thistle

Manual

If the plan has grown up to three feet tall then it may require that much more effort. Firstly, cut the leaves of plant on one side so that you can judge the position of the root of the plant. However, make sure that you pack the stems you have cut in a disposable bag or a plastic bag. If you leave the stems on the ground, they can germinate again after a few months by transferring the seeds to the soil. Now, once you can judge the root of the plant, use a shovel to dig about 1.5 to 2 inches below the soil surface. Cutting roots about 1.5 inches below the soil surface can do the job for you. However, you should do this before the plant has started flowering. Once you have cleared the area by uprooting the plant, make sure that you pack all the stems carefully and dispose them in an offsite location or burn them. Lastly, do not forget to mow the soil after a month again to prevent any spread further. You can also grow a plant like perennial grass, which is known to compete well with the bull thistle. If this does not work, you must contact local soil or agricultural department for their intervention.

Herbicide

This technique is best effective when combined with the manual technique of removing this plant. However, make sure that you use chemicals and herbicides that are animal friendly especially if you have a grazing land. 2,4-D is known to be a very effective herbicide and it is supposed to be animal friendly. However, you should contact the weed board in your state or country to get the best product suited for your soil and its inhabitants.

Biological

This could be a unique but effective way of controlling bull thistle in your area especially if the area is huge. Lady butterfly is known to control the production of bull thistle and it can survive well on the plant. Lady butterflies love the nectar of the bull thistle flower. The larvae of the seed head gallfly prevent the production of new seed in the plant.

Grazing

Goats, sheep and horses have been used to graze the land infected by bull thistle. Horses are known to eat the flower of the plant containing the seed.

Prevention

Lastly, prevention is the best cure in case of bull thistle. Firstly, all your efforts will go down the drain if the land next to you still has bull thistle. Therefore, if you are going for a weed cleaning program on your land make sure that your neighbor does it too. If you are cutting a bull thistle plant with a ripe seed head, make sure that you are extra cautious. Do not spill the seeds on the ground as even one seed can live beneath the soil for up to three years before becoming a plant. Secondly, keep mowing and tilling the soil even when you have no bull thistle in your area but have been infected before. This is because, bull thistles have the ability to resurface again a good one or two years after they have been removed.