Stinknet, also known as globe chamomile (Oncosiphon pilulifer), is a relatively new weed in Arizona that has quickly spread. The first herbarium collection for Arizona was made in 1997, and by 2019 the plant had risen to public attention due to its conspicuous presence. It is spreading along the I-10 corridor, becoming well established in Maricopa, Pinal and Pima Counties. The movement of people and vehicles through seed-laden stinknet infested areas has potential to dislodge seeds and may be a significant factor in its spread. Stinknet is a nonnative cool-season annual member of the sunflower family (Asteraceae). It may degrade rangeland as it crowds out other desirable cool-season plants. Stinknet is reported to be unpalatable to livestock, and shows little sign of damage by herbivory. It has been implicated in cases of respiratory distress, and there have been reports of contact dermatitis from skin exposure. Stinknet forms thick drifts of plants that are a particular problem for wildfire in Sonoran Desert vegetation. It dries and dies as Arizona enters its hot dry early summer, which is also wildfire season. It can then can catch and spread fire from an initial ignition source and carry flames from shrub to shrub and tree to tree. Combatting stinknet, especially larger infestations, and those in wildland situations, will require a long-term integrated weed management plan. Early detection of spot infestations and rapid response to pull and bag weeds before a seed reserve can build is key to preventing the spread of stinknet into new areas like Gila County. Agent Chamberland authored the following Extension bulletin on the subject: extension.ariz...
16 окт 2024
