Hazardous Plant Surveys

Plants which are potentially hazardous/toxic to humans were identified and mapped within the grounds of schools and care homes, a total of 18 sites. Management recommendations informed the client’s hazardous plant management plan.

EMEC Ecology were commissioned by the client to undertake hazardous plant surveys at several sites managed by the client. The sites comprised schools for children with disabilities and care homes for adults. When touched or consumed some plants pose a health risk to humans. As such, the client has a responsibility to remove or appropriately manage potentially hazardous plants on site, to minimise the risks to pupils/residents.

The surveys involved a walkover of the grounds of each school/care home to identify potentially hazardous plants. The locations of hazardous plants were mapped using QGIS software.

The hazardous properties of plants were researched using a range of resources, including handbooks such as Frohne (1984) and a variety of online resources. Plants were allocated a toxicity risk rating, based on the severity of effects:

Red: Highly toxic in small quantities, likely resulting in serious illness/potential fatality.

Amber: Toxic in small to medium quantities, resulting in potential moderate illness.

Green: Generally non-toxic but not for human consumption and could induce mild illness if consumed in large quantities.

Management recommendations were based on the toxicity rating and location of plants within the sites. Many of the hazardous plants identified throughout the sites occur widely across the UK and are often relatively common on residential sites. Whilst the removal of certain red-rated species was desirable to limit risks, eradication of all toxic plants would not be practicable or ecologically sound. For example, an individual hemlock plant was identified on one of the sites. In this case, eradication was appropriate due to the highly toxic properties of hemlock and ease of removal. However, ivy is a common, red-rated hazardous plant, and was widespread throughout many of the sites where eradication would have been impractical.

Where eradication was not appropriate, alternative management methods were recommended. These included pruning plants back out of the reach of pupils/residents, removing toxic berries, and regularly mowing lawns to suppress growth of toxic plants, such as buttercup and ragwort.