Though artichoke thistle may look attractive with its bright purple flower, there is no questioning this weed’s destructive nature to the Irvine Ranch Natural Landmarks. Its aggressive root system and rapid leaf growth steals light, water and nutrients from native plants. Each plant can also produce tens of thousands of seeds per year that are blown by wind or hitchhike on animals. If left unchecked, artichoke thistle can quickly spread across a landscape, displacing native plant diversity in its path. The artichoke thistle is one of the worst threats to natural habitat within the City of Irvine Open Space Preserve’s Quail Hill.
From 2011-2014, Conservancy staff and volunteers applied an approach known as “multi-cutting” to a designated area near the Quail Hill Loop. Since removing the entire root system of artichoke thistle in one go is an overwhelming task, multi-cutting instead cuts off portions of the plant above ground during repeated monthly visits, eventually resulting in its inability to grow back. After three years of this process, visitors to Quail Hill Loop in the beginning of 2014 witnessed the return of arroyo lupine (Lupinus succulentus) – whose native purple blooms benefit Irvine Open Space Preserve’s natural habitat much more than that of the invasive thistle’s flower. Encouraged by the diminishing amounts of artichoke thistle, Conservancy staff are now applying the same multi-cutting method to a new, comparably-sized habitat restoration area nearby along the loop trail.
While removing artichoke thistle with the multi-cutting method can be labor-intensive – some upper-body strength is required – little hiking is necessary and the reward for your hard work is knowing you’re helping native plants and local wildlife return to the Landmarks. Conveniently located near the 405 freeway and many neighboring communities, Quail Hill and its 733 acres of rolling grasslands provide ample opportunities for people to contribute to the care of this protected open space.
Pulling Together at Quail Hill is free with required registration, which closes at 4 p.m. the day prior to the event. While no special skills are required, all participants must be at least 14 years of age. All training and tools will be provided. For more details or to register, click on the title above or visit www.LetsGoOutside.org/activities.