Many people have been pitching to reduce the thistle infestations around our community, particularly in Round Valley. Thanks go out to the various groups as well as individuals who have put energy into this long-term project. Great progress has been made, yet there is still a ways to go.
If you are one who has been pitching in, it is important to know what is needed for your time to be well spent. Too often I see where well-intentioned people have simply cut off the flower stalk and left the plant untreated. This is wasted effort. The plant will simply put out three or four more flowers in a frighteningly short time.
To be effective, the root needs to be completely removed or killed. There are two ways to go about this.
One option is to pull the plant out of the ground and chop up the root. This can work except when the plant breaks off at ground level. In such cases, the hardy roots just carry on next year. This is a lot of work and it is easy to leave some root in the ground.
An easier and more effective option is to treat the plant with a strong herbicide. Roundup is effective on these hardy invasives. Applying any herbicide precisely with a narrow-beam spray bottle reduces overspray as well as the amount that is required to be effective.
Once the plant’s flowers have bloomed, one can assume fertilization has begun taking place. If the plant is treated at this time, it may eventually die, but it will put its last energies into producing seeds. So the best time around here for eradication efforts is May-early June, before the buds flower.
Once the buds are close to flowering, they need to be clipped off before treating the rest of the plant. And if the flowers have been open, they need to be clipped off, bagged and disposed of off-site. The remaining plant still needs to be treated with herbicide.
Last, make sure you have a sturdy pair of leather gloves and good garden clippers. Light gardening gloves and thin leather types provide no defense against thistle thorns.
Michael Tanksley
Park City