Officials at the Casa Grande Ruins National Monument recently declared the picnic area closed due to the density of the offensive and noxious winter weed.

Although Stinknet (also known as Globe Chamomile) has pretty, yellow ball-shaped blossoms and grows to more than 2ft tall, it has an extremely potent smell not dissimilar to burnt rubber or nail polish remover.

According to the University of Arizona, this toxic plant can cause serious breathing problems as well as severe skin rashes and is highly flammable.

Officials at the Coolidge attraction are asking visitors not to walk near or step on the flowering weed to avoid spreading it and staff are working on a solution to get the area reopened as soon as possible.

Perhaps one of the best-known attractions in Coolidge, the monument showcases the ruins of an Ancestral Sonoran Desert farming community which includes the preserved Casa Grande (Great House). The structures were built more than 700 years ago by the Hohokam tribe.

Stinknet spread widely in Maricopa County during the wet autumn and winter seasons of 2016, 2018 and 2019 according to the Arizona Native Plant Society, which caused heavy infestations.