Description
Foxglove digitalis purpurea. L is an erect biennial or perennial herb planted extensively as an ornamental in flower beds, particularly in the "cottage garden" style and is a common garden escape. The life span of the plant is two seasons, with a rossette of leaves 150 to 300mm in length, they are soft, densely hairy, toothed, ovate and lance-shaped leaves in a basal rosette. Second year growth produces flowering stems, up to 150 cm in height, and on their terminal 250 to 500mm they carry tubular bell-shaped flowers that are stalked, white, yellow, purple or pink with mottled patterns, with all the flowers hanging on one side of the spike. It is propagated from seeds which are minute and numerous, dispersed by wind and water. It is frost resistant, drought sensitive and prefers moist soils in open positions.
First year growth has been misaken for comfrey (Symphitum officinale) with fatal results. Although, ingestion of this plant can be fatal at any time during the life of the plant, it is most toxic just before the seeds ripen. The upper leaves of the stem are also more toxic than the lower leaves.
Range
Native to Britian and Europe, this plant is widley cultivated and has been listed as a weed in Spain, Brazil, Chile, New Zealand, Turkey and the United States. It thrives in siliceous or loam soil, but needs very little soil to survive. It is often found in the crevices of granite walls, dry hilly pastures, roadsides, logged-off areas, and rocky places.
It has naturalised from the central coast of New South Wales to southern and eastern Victoria and throughout many regions of Tasmania. In Victoria, it has invaded moist and wet sclerophyll forest, riparian areas and rain forest. Infestations also exist in alpine areas.
Current Distribution
In the Meander Valley Region, it considered a weed of concern as it has the potential to develop into a significant problem in plantation areas and roadsides in State Forests in the Upper Liffey River catchment and areas of private and Crown Land in the Jackeys Marsh, near Meander. Nurseries still continue to sell seedlings and seeds. Dumping of garden plants is a cause of new infestations in the Municipality.
Toxic Agent
Many of the common names of this plant pertain to its toxic nature (Witches' glove, Dead Man's Bells, Bloody Fingers). Foxgove belongs to the Figwort Family (Scrophulariaceae) and the whole plant is toxic, it contains various cardiac glycosides. Symptoms include dizziness, vomiting, irregular heart beat, and delerium or halucinations.
Upon ingestion, this plant can cause toxic reactions that lead to severe sickness and death in animals and in humans. Several important pharmaceutical drugs such as digitalis and digozin are derived from this plant. The chemicals increase the force of contraction of the heart muscle and are therfore used in cases of heart congestion. However, the theraputic dose is dangerously close to the lethal dose. Historically, Foxgove was employed by herbalists for a variety of purposes, from an ointment used for cleansing wounds and reducing swelling to boiling it and using it as an expectorant.
All classes of livestock are susceptible to poisoning by foxglove. However, because of the unpalatable nature of the plant, poisoning is infrequent, although when it does occur it is often severe and dramatic, frequently resulting in death. Human poisoning occurs rarely. However, poisoning was reported in the children who ate the flowers or drank water from vases. Accidentally including foxglove leaves in tea has led to poisoning and death. Cardiac glycosides are commonly described drugs that have a low margin of safety. Slight over doses of prescribed medicine can cause sympoms of toxicity.
CONTROL
Hand Pulling
Pull, cut or hoe the plants before Christmas, paying most attention to the best land, and doing that thoroughly. Collect flowers and fruit for proper disposal.
Chemical
Foxglove can be controlled by spraying with M.C.P.A. or 2.4.D in the young stage. In the mature plant stage wick wipe rosettes with 33% glyphosate in water. Spot spray with glyphosate (eg Roundup 360 or Weedmaster 360) or triclopyr (eg Garlon 600).
 
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