Scotland Unleashes Hungry Sheep to End Invasive Toxic Giant Hogweed

According to the findings of four-year research in Aberdeenshire, Scotland, hungry sheep can aid in the fight against the growth of the giant hogweed, an invasive and highly toxic plant.

Hungry Sheep Vs. Invasive Species

Giant hogweed can reach a height of 16 feet, and its sap can severely burn skin.

Pesticides can be sprayed on the invasive plant to control it, or flower heads can be cut off to stop seed production. Repeated grazing by sheep has been found to destroy the plant.

Since 2019, the Scottish Invasive Species Initiative (SISI) has kept an eye on sheep in a region where hogweed is common along the River Deveron. According to the study, the taproot of the plant died off as a result of the sheep grazing it, untouched by the sap's toxicity.

According to SISI, this experiment may pave the way for the grazing of sheep in other locations. Project officer Karen Muller emphasizes the value of monitoring to establish the proper grazing balance and safeguard native flora. Over time, Muller's team lowered grazing pressure and set up a hogweed control system with little harm to the local flora.

Dan Gordon, the landowner, is pleased with the development at the location.

Gordon claims that employing pesticides to combat the dominating hogweed would have been difficult and expensive, making the SISI alternative technique quite welcome and effective.

Invasive and Toxic Giant Hogweed

The 19th century saw the introduction of giant hogweed as a beautiful plant in British gardens. Giant hogweed is a native of the Caucasus Mountains in Europe and Central Asia.

Each flowering head can yield up to 50,000 seeds, and it spreads swiftly, BBC News reports.

Giant hogweed (Heracleum mantegazzianum), a near relative of cow parsley, is a native of Southern Russia and Georgia. It has a height of more than 10 feet. Although this remarkable plant has the potential to be appealing in some circumstances, its sap may severely burn the flesh and most gardeners will want to get rid of it because it is possibly invasive. It is commonly found in the wild and presents a significant risk to those who are ignorant of its potential for harm.

Even though it has an amazing appearance when fully grown, giant hogweed is invasive and might be harmful. Chemicals in the sap can lead to photodermatitis or photosensitivity, conditions in which the skin becomes extremely sensitive to sunlight and may develop blisters, pigmentation, and permanent scars, according to the Royal Horticultural Society.

Managing Invasives with Sheep

The study found that sheep have been very successful at controlling giant hogweed, taking up most of the seedlings, young plants, and huge adult plants.

Initial overgrazing resulted in a rise in unpleasant species, such as nettles, bracken, and thistles, ground theft, the extinction of herb species, and the grazing of shrub and tree seedlings.

Initially, sheep should graze at a low intensity. By taking into account observations of the amount of gigantic hogweed as well as changes in the vegetation and bare ground, grazing pressure can be regulated.

Before feeding on giant hogweed, the sheep might need some acclimatization time. However, they quickly come to prefer it, and this preference lasts through all grazing seasons.

Most of the animals utilized in these tests have been Blackface and Greyface sheep. Blackface sheep's dark skin pigmentation may assist them fend off the effects of gigantic hogweed sap's photosensitivity. No negative effects on the sheep from eating gigantic hogweed were observed during the studies, according to the study recently conducted and published by SISI.