Weed Spotter Queensland Network Newsletter Autumn 2012 edition

When the BioSecurity Queensland risk assessment of
the Amazon frogbit came back as ‘high’ and it was the
first naturalised record in Queensland, the Redland City
Council promptly mapped its distribution and discovered
it in an adjoining water body. Within a week, in May
2011, the first treatment was undertaken. Follow-up
treatments continued every two weeks for two months,
then monthly. Monitoring was carried out at the same
time.
There has been no evidence of the Amazon frogbit
for some months now and it is hoped that due to a
confirmed identification and quick response it has
been eradicated from the Redlands area. This situation
Initial treatment of frogbit. Photo: Redland City Council.
Eradication of frogbit achieved. Photo: Redland City Council.
What’s happening?
Weeds of Northern Australia: A Field Guide by Nicholas
Smith is now available. Further information on costs and
postage is available by contacting .
The Australasian Weeds Conference is to be held in
Melbourne, 8–11 October 2012.
The next Queensland Weeds Symposium will be held in
South East Queensland in July 2013.
Page 2
shows the importance of early detection and how each
weedspotter can contribute to preventing the spread of
new and emerging weeds.
In an unusual twist, the native frogbit (Hydrocharis
dubium syn. Limnobium dubium) is now thought to be
non-native (Bean 2011).
References
Bean, A.R. (2011). Hydrocharis dubia (Blume) Backer
(Hydrocharitaceae) is an alien species in Australia.
Austrobaileya 8(3): 225–440.
Boyd Essex, Redland City Council.
Midway in treatment of frogbit. Photo: Redland City Council.
Emergent habit of frogbit when crowded. Photo: Redland City
Council.
Weeds of the Mackay District publication is presently in
production.
The first weeds phone app for Queensland is now a
reality. Weeds: the ute guide is now available for iphone.
It covers western weeds of grain crops, refer to
.
There is an online interactive lucid key to Australian
weeds now available from .