The following blog was written by Linde Hess a digitiser in the Herbarium.

Since 2021 we have increased our digitisation capacity with the goal of getting to 1 million specimens imaged by Autumn 2024. Each digitiser is assigned a family of plants to work through. This series of blogs will spotlight the families that have been completed by a member of the team.

The Hypericaceae family is commonly known as the St. John’s wort family. This family name was first published in 1789. Its distribution is nearly worldwide except very cold or very dry regions. The genus Hypericum has an almost global distributuin, while the genus Cratoxylum only occurs in Southeast Asia, and genus Eliea is endemic to Madagascar. Hypericaceae are herbs, shrubs or trees, rarely climbers.

St. John’s wort (Hypericum perforatum) is the most abundant species in this family in our collection: we have 479 St. John’s wort specimens.

Around 1880, St. John’s Wort was introduced into Australia and New Zealand as a garden plant and is now considered an environmental weed. Besides reducing the carrying capacity of the pasture, livestock may become affected with ‘wort dermatitis’, for the hypericin in the plant acts on the nervous system, rendering the exposed non-pigmented areas of their skin photosensitive. Control measures of various kinds are being tried, including improvement of the pasture by sowing competitive species, chemical treatment and the liberation of insect parasites. Nature 152 (1943).

St John’s wort is a popular herbal remedy promoted for the treatment of depression. While there’s evidence of its effectiveness, many experts advise against its use, because the amount of active ingredient varies among individual brands and batches, making the effects unpredictable. NHS

Our Collections

Before mass digitisation we had cataloged 3,689 specimens, following mass digitisation there were 6,989 specimens, of which 142 are type specimens.

The specimens can be viewed through our herbarium catalogue here.

Top 5 regions

No. of Specimens	Herbarium Filing Region
1,258	West Asia
1,076	Europe excl. Britain and Ireland
978	Britain and Ireland
674	North America
640	Inner Chine, Korea and Taiwan

Top 5 Genera

No. of Specimens	Genus
6,366	Hypericum
260	Cratoxylum
129	Vismia
81	Ascyrum
43	Psorospermum

We have relatively few Hypericaceae specimens from New Zealand, while there are several native Hypericum species present. The genus Eliea is represented by only two specimens in our collection, this is not surprising as the genus is endemic to Madagascar.

Interesting specimens

Although St. John’s Wort was first recorded in New Zealand in 1869 and is now considered an environmental weed, we have no NZ specimens in our collection. Here is our only Australian specimen, collected from the roadside not far from Adelaide.