52 Plant Protection Quarterly Vol.12(2) 1997
body of previous research results. Only
with such integration and increased cooperation will more effective control of St.
John’s wort populations in both natural
ecosystems and perennial pastures beachieved. Whilst much has been learned
and applied in the last 60 years, much remains to be done. It is the task of thisworkshop to achieve by consensus a priority list of tasks for the next six years that
may be achievable by the CRC and its cooperating research agencies.

History of the introduction and spread of St. John’swort (Hypericum perforatum L.) in Australia
J.A. HarrisA and A.M. GillB
Faculty of Applied Science, University of Canberra, PO Box 1, Belconnen, ACT
2616, Australia.
B
CSIRO Division of Plant Industry, GPO Box 1600, Canberra, ACT 2601,
Australia.

A

References

Abstract

Briese, D.T. (1997). Biological control of St.
John’s wort: past, present and future.
Plant Protection Quarterly 12, 73-80.
Campbell, M.H., Briese, D.T. and Delfosse,
E.S. (1995). Hypericum perforatum L. In‘The Biology of Australian Weeds’, eds.
R.H. Groves, R.C.H. Shepherd and R.G.
Richardson, Volume 1, pp. 149-67. (R.G.
and F.J. Richardson, Melbourne).
Campbell, M.H, May, C.E., Southwell, I.A.,
Tomlinson, J.D. and Michael, P.W.
(1992). Variation and varietal determination in Hypericum perforatum L. (St.
John’s wort) in New South Wales. Plant
Protection Quarterly 7, 43-5.
Clark, N. (1953). The biology of Hypericum
perforatum L. var. angustifolium DC. (St.
John’s wort) in the Ovens Valley, Victoria, with special reference to entomological control. Australian Journal of
Botany 1, 95-120.
Currie, G.A. and Garthside, S. (1932). The
possibility of the entomological controlof St. John’s wort in Australia – progress
report. Council of the Scientific and Industrial Research (Australia) Pamphlet
No. 29.
Dodd, J. and Scott, J.K. (1997). St. John’swort (Hypericum perforatum) in Western
Australia. Plant Protection Quarterly 12,
57-9.
Griffith Davies, J. (1942). Pasture researchby the Division of Plant Industry. Journal of the Council for Scientific and Industrial Research 15, 250-2.
Groves, R.H. (1989) Ecological control ofinvasive terrestrial plants. In ‘BiologicalInvasions: A Global Perspective’, eds.
J.A. Drake et al., pp. 437-64. (Wiley,
Chichester).
Harris, J.A. and Gill, A.M. (1997). Historyof the introduction and spread of St.
John’s wort (Hypericum perforatum L.) in
Australia. Plant Protection Quarterly 12,
52-6.
Robson, N.K.B. (1968). Guttiferales. 109.
Guttiferae (Clusiaceae). In ‘Flora
Europaea’, Volume 2, pp. 261-9. (Cambridge University Press, Cambridge).

Hypericum perforatum has been introduced into Australia a number of times,
the first being more than 100 years ago. It
was cultivated in the Melbourne and Adelaide Botanic Gardens in 1858 and 1859,
respectively, for potential use in homegardens. The earliest recorded outbreakof the wort was in 1880 at Bright, Victoria; i.e. escaped from a local garden where
it was planted for medicinal purposes.
Another outbreak occurred at Coromandel Valley in the Adelaide hills, possibly as early as 1881, and certainly by1886. The earliest outbreak in New South
Wales seems to have occurred at Mudgee
in 1890 from either horse fodder or as a‘garden escape’. It now occurs in all
States. Herbarium records suggest that its
range was still increasing in the 1980s.
Today it is still abundant in some localities, particularly in south-eastern Australia. For example, in 1986, 200 000ha of
the Tablelands of New South Wales wereheavily infested with the wort.
The pattern of spread of St. John’s wort
has consisted of increasing numbers of
isolated occurrences from which expansion has occurred until they coalesced.
Spread rate was most rapid, perhaps
through the accidental movement of seedassociated with the movement of stockand their fodder, as well as through ‘garden escapes’ following deliberate plantings for horticultural use.
Initially an agricultural problem, it is
now more of a problem along roadsides
and easements and in non-agriculturalland, generally. Low levels of disturbance, such as mowing-burning-scarifying increased populations whereas frequent, intensive disturbance such as repeated ploughing used in tobacco cultivation, eliminated it. Population explosions
could well be attributed to a changed disturbance regime in a locality, and/or seedlongevity. That seeds may lie dormant in
the soil for many decades underscores theability of the species to ‘return’ to a site
after a prolonged absence (such as underpine plantations) and to some extent independent of the cause of that absence.

Introduction
For over a century St. John’s wort, Hypericum perforatum L (family Clusiaceae), hasbeen a problem plant in Australia. In 1883,
a writer to the ‘Alpine Observer’ (Hortus
1883) exhorted the Bright (Victoria) ShireCouncil to control the ‘noxious ugly plant’
growing so luxuriously about the racecourse, a plant which had been identified
by the Victorian Department of Agriculture as the ‘ordinary St. John’s wort of Britain’ (Martin 1883). Various methods ofcontrol were suggested. Over 100 years
later, in 1986, ‘St. John’s Wort is still one of
the most troublesome tableland weeds’
heavily infesting more that 200 000 hectares in New South Wales (Freebairn1986).
The seriousness of the problem that St.
John’s wort posed in 1928 (and today) tofarmers is illustrated by the comments of amanger of the Manus Estate, Tumbarumba, New South Wales (NSW):‘Two hundred and forty merino sheep
were drafted into a paddock where
there was an infestation of about 50%
St. John’s wort, the rest being grass. At
the end of two months, forty of the
sheep died. Others were blind, andsome had the skin of the face and shins
peeled off, leaving raw flesh. All of the
sheep had shed the whole of their wool,
and went mad at the slightest touch ofwater’ (Tillyard 1928).
Problems due to wort include loss of pasturage, photosensitization, abortion andloss of milk production (Campbell andDelfosse 1984). Tainting of cow’s milk is aproblem in dairying areas (Muenscher
1951).
St. John’s wort has had a long andmostly unwelcome presence in Australia
despite persistent attempts at its control. A
review of the history of its introduction
and spread was undertaken to understand
why this is so. Two localities receive special attention. Bright, in north-eastern Victoria, has been given as the first site of St.
John’s wort in Australia outside of Botanic
Gardens and, together with the second locality of Tumbarumba, was the site of thefirst entomological research into the control of the plant. Manus, near Tumbarumba in south-eastern NSW, was the siteof extensive experiments on agronomic
and chemical methods of control by the
NSW Department of Agriculture and theCouncil for the Scientific and Industrial
Research (CSIR), now CSIRO Australia.

Plant Protection Quarterly Vol.12(2) 1997 53
The aim of this brief review is to provide
an historical context for the more technicalresearch on the biology of the plant andmethods of control. We have cited newspapers, letters, and internal papers, notbecause of any confirmable veracity they
may have, but rather because of the lackof information on certain topics in the scientific literature, and the historical perspective which these documents provide.

Establishment of St. John’s wort inAustralia
Determining when and where H.
perforatum first grew in Australia is difficult. French (1905) noted that ‘an old lady
introduced the seeds from Germany for
medicinal purposes’ in about 1880 andgrew the plants in her garden in Bright,
Victoria (Figure 1). The plant subsequently spread to the Bright racecourse
and received the name ‘racecourse weed’.
It is likely that the following (Anon. 1880)
refers to St. John’s wort: ‘The engineer was
instructed to employ labour to destroy
thistles in the streets of Bright and theplant growing near the racecourse’ (ouremphasis). The occurrence at Bright is particularly significant in being the origin of
the wort outbreak in Australia, but it was
not the first importation to Victoria. Baron
Ferdinand von Mueller, the Director of the
Melbourne Botanic Gardens, refers to it as
being in cultivation at the Gardens in 1858
(Mueller 1858).
There is no evidence that the Melbourne planting became the source of anaturalized population in the manner ofthe Bright planting. It is also unlikely thatthe first South Australian outbreak wasmade from Victoria. A specimen was collected in 1881 (Adelaide Herbarium sheet
AD 95651005) from Coromandel Valley
near Adelaide (P. Kloot personal communication 1986) where a species, probably
H. perforatum, was reported as a weed in1901 (Anon. 1901) under the name H.
canariense. Summers (1904) asserted thatH. perforatum was first noticed in
Coromandel Valley in about 1886.
Hypericum perforatum was grown earlyin the Adelaide Botanical Gardens (Francis
1859) under the name H. calycinum L. (P.
Kloot personal communication 1986). Cultivation in a botanical garden implies a recommendation for horticultural use and,indeed, an herbaceous perennial Hypericum, 0.6–1.2 m tall with yellow flowers
was recommended for planting in homegardens as early as the 1870s (Heyne 1871,
1877, 1881).
St. John’s wort was either deliberately
introduced into Eaglevale Station, in
Gippsland, Victoria, or accidentally introduced and protected because of the beautyof its flowers (Tillyard 1928). The plant was
similarly introduced to the area of
Tumbarumba, NSW, (Tillyard 1928). The
outbreak at Mudgee, NSW, began either

Figure 1. The house of the ‘old lady’ at Bright from which St. John’s wort wasthought to have spread in the 1880s (from French 1905). Reproduced withpermission.
as a garden escape (Currie 1929) or fromimported fodder (Roe 1940). Maiden(1901) recorded St. John’s wort from
Mudgee before 1901 while a correspondent from the NSW Department of Agriculture to CSIR Division of Entomology (February 1940) noted that: ‘The infestation is avery old one, and according to local history dates back to about 1890’.
The above evidence suggests that multiple entry and establishment have occurred. The following contemporary evidence confirms it:i. morphological and physiological studies of variation in St. John’s wort
populations in Australia are consistent
with multiple entry and establishment(Campbell 1985),
ii. plants grown from seed imported from
Germany and being cultivated for medicinal use were discovered in southern
NSW in 1985 (P. Gorham NSW Department of Agriculture personal communication 1986).

Distribution
There has been no systematic study of the
spread of St. John’s wort in Australia. Our
information comes from numbers of observers using various methods. We havesupplemented the data of Campbell andDelfosse (1984) on areas of infested country and numbers of shires infested to varying degrees in Victoria and NSW, with further data, e.g. from Jose and Carter (1926)
for areas affected in Victoria and fromgovernment Gazettes of Victoria and
NSW for details of numbers of shires forwhich St. John’s wort was declared to be a
problem plant. In addition, we report information derived from a collation of herbarium records of Federal and State herbaria: districts represented by 1:250 000

map sheets in which St. John’s wort has
been collected and mapped cumulatively
by decade (Figure 2). Note that a single
collection of a small infestation can occur
as a large shaded area on the map: thus, it
should not be inferred from the maps thatthe species is to be found throughout theshaded area. Indeed, populations in Western Australia, South Australia, Tasmania
and Queensland are small (Campbell andDelfosse 1984).
The herbarium records suggest a
steady rate of spread from 1890 to 1940
after which spread continued at a slower
rate until the present. The numbers ofshires recording St. John’s wort as an actual or potential problem showed a relatively slow rate of initial spread followed
by a rapid increase. While 35 shires in NSW
had declared St. John’s wort noxious to1921, there were 76 shires in which theplant was thus declared in 1977 (Campbell
1977).
Neither the herbarium data nor thosefor the numbers of declared shires canshow that the plant has possibly been lostfrom some areas while expanding in others. Shepherd (1983) revealed an ebb andflow to the presence of the plant in various
inspection districts of Victoria.
Areas of Victoria in which St. John’swort occurs have been recorded sporadically throughout its history. French (1904)
reported that 67% of infested land was privately owned (2283 ha) while in 1916 thisfigure was only 15% but in absolute terms
was a much larger area (11 340 ha). By
1948–50, by far the greater part of the occurrence of the species was on timbered
land and dredgings (Clark 1953), presumably public land. Similarly, Shepherd(1983)—30 years later—reported that 7% of
infested land was agricultural (12 250 ha)

54 Plant Protection Quarterly Vol.12(2) 1997
1881–1890

1921–1930

1931–1940

1971–1980

Figure 2. Maps of the cumulative spread of Hypericum perforatum in Australia as determined from herbarium
specimens.
while 83% was in unsown native forests. If
we can equate privately owned with agricultural, above, there was only a slight net
increase in agricultural land affected by St.
John’s wort from 1916 to 1983 in Victoria(11 000–12 000 ha).

Methods of spread
The pattern of spread of St. John’s wort
has consisted of increasing numbers of
isolated occurrences from which expansion has occurred until, at times, they coalesced. The detailed maps of early distributions show the discontinuous nature of the
distribution (French 1905) as do thecoarse-grained maps from herbarium
records (Figure 2). In north-eastern Victoria, the map in French (1905)—probably
prepared by Davey (1921)—shows the
major area of occurrence to be linear along
the Ovens Valley, but there were also

isolated occurrences around Wangaratta,
Rutherglen, Tallangatta and Omeo, for example.
The outbreak in north-eastern Victoria,
beginning at Bright about 1880, hadspread in a more-or-less continuous fashion to Everton—about 50 km away—by
1905 (French 1905). Thus the average linear rate of spread was approximately 2 km
a year. What method(s) of spread could
account for this rate?
Vegetative spread is too slow to accountfor the major features of distribution but
can be important locally (Clark 1953). The
expansion of a single plant by its rhizomes
over a period of five years until it became‘a densely infested patch of weed about
100 square feet in extent’ was measured(Tillyard 1928). Assuming a circular infestation, the linear rate of spread implied bythese figures is approximately 30 cm per

year which is about four orders of magnitude too slow.
Wind is another possibility as the seeds
are very light, about 0.14 mg each(Campbell and Delfosse 1984), and produced at heights above the ground of up
to 1.2 (Ewart and Tovey 1909) or 1.4 m(Tillyard 1928). However, numbers ofseeds in traps of area 0.21 m2 (18 × 18") at
distances of 3.1, 6.2 and 9.3 m (10, 20 and 30ft) from the downwind edge of an H.
perforatum stand were only 148, 27 and 7
respectively (Tisdale et al. 1959). While nodata were given for the height of the standor number of seed at the origin, the data
show that most seed falls near the parent
plants and that maximum dispersal distances by wind are likely to be of the orderof only 10 m per year.
The linear distribution of the wort
down the Oven’s Valley from BrightPlant Protection Quarterly Vol.12(2) 1997 55
suggests that distribution by water occurs.
However, the species was distributed upstream for tens of kilometres, as well as
downstream, and the seed is not at all
buoyant (Davey 1917). It is probable thatwhole plants, seeds or soil , would havebeen eroded from river banks and been
carried downstream during floods or during the period of extensive mechanicaldredging for gold that took place aftermining began in 1852 (Robertson 1973).
The sticky capsules of H. perforatum
break off and may adhere to animals(Davey 1922, Calvert 1932, Parsons 1957,
Robertson 1973). From the Ovens Valley
cattle were taken up to surrounding
subalpine country as early as 1878 (Holth1980). The animals were driven up during
spring (before the summer flowering of
the wort) and down again around Easter(when capsules may have been ripe). Cattle travelled substantial distances by footin this regional migration even moving
into NSW (Davey 1919). Horses may havecarried capsules to and from the mountains during the autumn muster. Rates ofdispersal of 2 km per year in this way are
possible but not documented. French(1905) declared that ‘hay or other cereal
crops …[from wort-infested land, is themeans by which] …the seed of the weed
has been largely distributed’.
Feral animals, such as rabbits (Davey
1917), foxes and horses, could carry seedin their coats just as domestic animals
could. Similarly, native animals could alsotransport seeds, the maximum dispersal
most likely being by dingoes and kangaroos. Birds are unlikely to deliberately pickup the seeds, while harvester ants, which
can transport the seed short distances(Tillyard 1928) may also consume it.
There are many other means of transport possible apart from those listed
above such as in faeces (Calvert 1932), in
soils carried by animals on their feet, in soil
on cars, or in soil supporting pine seedlings from invested areas (Parsons 1957).
Deliberate movement is also important.
People have grown the plant ornamentally, including eminent botanists, without
realizing the weedy potential of the species.

Infestations at Manus
Nearly half of the 12 000 ha (30 000 acre)property ‘Manus’ (Whitworth 1866) of the
McMicking family near Tumbarumba,
NSW, was chosen in 1916 for closer settlement by soldiers. Inspection then revealed
that there was no noxious weed to be seen
(NSW Closer Settlement Advisory Board
1916). Within a decade ‘The spread of St.
John’s wort became so serious …that special steps were taken …to check the menace’ (NSW Department of Lands 1926). All
methods of control, with the possible exception of goat grazing, have since been
tried at Manus.

At the time of acquisition in 1916, there
were 11 share farmers on Manus, nine ofwhom contributed milk to the homesteadcheese factory (NSW Closer Settlement
Advisory Board 1916). The NSW Department of Lands recommended that the acquired 5000 ha (12 560 acres) be subdivided into 35 farms, but by 1920 there
were only 26 farms occupied from theavailable total of 29 (NSW Department ofLands 1920).
Most of the new settlers on the Manus
were dairy farmers who, ‘particularly during the period 1918 to 1928 …encouragedby high wheat prices, were continually
cropping their land with wheat’ (Moore
and Cashmore 1942). Populations of St.
John’s wort expanded so much during thisperiod that the cost of control exceeded
the value of the land (NSW Department ofLands 1926).
The only quantitative data to help explain this population explosion come fromtrials by Moore and Cashmore (1942) at
Manus. They found that, on plots open to
grazing, St. John’s wort yielded 270 kg perha (2.16 cwt per ac) on untreated land, 780
kg per ha (6.23 cwt per ac) on previously
ploughed land, and 980 kg per ha (7.81 cwt
per ac) on land mown, burnt and scarified.
Other intermediate-level disturbancessuch as those associated with the cutting oftimber on the slopes of the Ovens Valley
also exacerbated the growth of populations of the wort (Clark 1953) but with intense disturbance—such as oft-repeatedploughing for tobacco farms in the Ovens
Valley—the wort could be locally eradicated (Davey 1921).
At Manus, St. John’s wort was so bad in
1926 that approximately 1400 ha (3500
acres), or nearly one quarter of the Closer
Settlement Area, were handed over to the
NSW Forestry Commission for afforestation by conifers. Ewart and Tovey (1909)
had suggested afforestation as a solution
to the wort problem in the Ovens Valleyand Pinus insignis Dougl. ex Loud. (=P.
radiata) was planted there in 1916
(Robertson 1973). As pines over-topped
the wort they first suppressed them andlater killed them. Fuelbreaks remained infested, however, and any thinning or falling resulted in the reappearance of thewort, presumably from seed stored in thesoil over several decades (see Appendix).
In wort-infested pine plantations ‘Hypericum is the last to be excluded …and thefirst to reappear’ (Clark 1953). Hence, thewort could be expected to return to pine
plantations or farms after several decades
should cultivation become less intense,and provided there are seeds lying dormant in the soil.
Initially an agricultural problem, St.
John’s wort is now more of a problem
along roadsides and easements and in
non-agricultural land generally. Where it
has been successful can be depicted using

the framework of disturbance regimes, aregime consisting of particular types, frequencies, intensities and seasons of disturbance. Types of disturbance include fires,
fertilizers, cultivation and mowing. Low
levels of disturbance, such as mowingburning-scarifying increased populations
whereas frequent, intensive disturbancesuch as repeated ploughing eliminated it.
Population explosions could well be attributed to a changed disturbance regime in a
locality, and/or seed longevity. That seeds
may lie dormant in the soil for many decades underscores the ability of the species
to return to a site after a prolonged absence (such as under pine plantations) andto some extent be independent of thecause of that absence.

Conclusion
Hypericum perforatum has been introduced
into Australia a number of times, the firstbeing more than 100 years ago. Like many
weeds its history is closely tied to the history of people and their activities.
The long history of St. John’s wort inAustralia shows that such unwanted species are not easily eliminated or controlled
perhaps due to great seed longevity andability to grow in moderately disturbed
sites common across a wide spectrum ofdeveloped landscapes from peri-urban
through to forestry, agricultural and mining areas.

Acknowledgments
We appreciated valuable discussion with
Messrs. G. Martin and J.D. Williams andDrs. M. Campbell, E.S. Delfosse, D.
Denholme, D. Dibley, R. Groves and D.
Briese. The Forests Commission of NSW
kindly allowed us to work in the Manus
Plantation. Mr. P.H.R. Moore provided
able technical assistance in the field, glasshouse and laboratory.

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Anon. (1901). Cherry Gardens, December
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South Australia 4, 543-4.
Calvert, J. (1932). St. John’s Wort in Australia. Journal of the Council for Scientificand Industrial Research 5, 52-8.
Campbell, M.H. (1977). Assessing the Area
and Distribution of Serrated Tussock(Nassella trichotoma), St. John’s Wort
(Hypericum
perforatumvar.
angustifolium) and Sifton Bush (Cassinia
arcuata) in New South Wales. Department of Agriculture New South Wales
Technical Bulletin 18.
Campbell, M.H. (1985). Germination,
emergence and seedling growth of Hypericum perforatum L. Weed Research 29,
259-66.
Campbell, M.H. (1986). St. John’s wort.

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New South Wales Department of Agriculture Agfact P7.6.1, second edition.
Campbell, M.H. and Delfosse, E.S. (1984).
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Clark, N. (1953). The biology of Hypericum
perforatum L. var. angustifolium DC. (St.
John’s wort) in the Ovens Valley, Victoria, with particular reference to entomological control. Australian Journal of
Botany 1, 95-120.
Currie, G.A. (1929). Report on a visit toBathurst, Mudgee and Orange. Council
for Scientific and Industrial Research,
Internal Report.
Davey, H.W. (1917). Weeds. Journal of the
Department of Agriculture, Victoria 15,
427-34.
Davey, H.W. (1919). Experiments in thecontrol of St. John’s wort. Journal of the
Department of Agriculture, Victoria 17,
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eradication. Journal of the Department ofAgriculture, Victoria 19, 661-4, 705-14;
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Appendix: Assessment of the seedlongevity of Hypericum perforatum
When a pine plantation reaches stand closure, H. perforatum may disappear
vegetatively but remain at the locality inthe form of seed in the soil. Thinning thestand may enable seed in the soil to produce mature plants in the area once again.
We chose an unthinned Pinus ponderosa
plantation (Block 57) planted in 1937 on the‘Manus’ estate near Tumbarumba for aninvestigation of soil seed. This area wasplanted to pines because of the dense
growth of St. John’s wort there in the
1930s (see text). There were a few
aetiolated plants of H. perforatum under thepines in 1983 but none of these flowered
and all died.
Ten soil-core samples of 8 cm2 surface
area and 5 cm deep were taken from under the litter from an area 2 × 1 m between
rows of trees or beyond the plantation
boundary. The sampling procedure was
replicated three times at each site. There
were three sites within the plantation andtwo outside it (one above the plantation
edge, one below). All sites were at least 20
m from the plantation edge. Samples
within each replicate were combined andthen sieved using a 3 mm mesh sieve, thelarge material being discarded. The finermaterial was spread on trays of sterile
sand in a 20/16°C glasshouse in September 1983. Germination was assessed overa one year period and a few plants weregrown to maturity to confirm identity as
H. perforatum.
Germinants of Hypericum were, for replicates combined at each site, 326 and 73
for the upper and lower sites outside theplantation and 350, 387 and 547 for thesites within the plantation. For the plantation sites these figures represent a densityof seeds of 1.5–2.3 per cm2.
Canopy closure of these pines would be
expected to take place in 8-10 years fromplanting (R. Gay, forester, personal communication). If all Hypericum had died bythis time, then seed longevity of at least 36
years would be expected. If canopy closure took longer for this poorly growing
stand—say 20 years—the longevity of
seed would still be 26 years.