PLANT PROTECTION 1 – Pests, Diseases and Weeds

PLANT PROTECTION 1 – Pests, Diseases and Weeds
HOW MUCH OF
THE BOOK
SHOULD BE
STUDIED?
?
SYSTEMATIC STUDY
Causes of plant problems should be studied systematically, preferably
starting with insects and allied pests in autumn, they are easy to collect and
study, most people find them interesting.
However, it is not necessary to cover all the problems within each group, but
rather that some be selected for more or less detailed study.
Always include some important local pests, diseases and weeds.
PRACTICAL EXPERIENCE
To obtain sufficient practical experience in examining fresh material and
diagnosing plant problems, the following activities may be undertaken:
Bringing specimens to class. Students are encouraged to bring specimens
for class study and diagnosis.
Seasonal pests, diseases and weeds can be examined when available.
Regular testing. Initially students can examine seasonal specimens according
to their cause. After a few weeks and some experience has been acquired,
regular weekly or fortnightly self-testing of selected specimens can commence.
Field studies. Take every opportunity to examine problems in the field at
different times of the year but especially during spring and autumn, field
studies are of most benefit towards the end of the course, when students have
acquired some skills. Examine real plant problems at work and in gardens, ask
colleagues and friends. Plant clinics and advisory services can be useful aids.
Emailing photographs to diagnostic services.
Many insects and weeds can be readily
identified from pictures sent to a diagnostic
service – Christmas beetle.
Some diseases have distinctive symptoms and
a general identification can be made from photos
sent to a diagnostic service – rose ‘mosaic’.
Many diseases can be difficult to identify from
symptoms and may require fresh material,
knowledge of the plant, its history and/or specific
tests for identification – the plant is Choysia.
What questions might you want to ask?
Fresh material with
the enquirer is often
questions
Plant clinics can provide a range of plant problems
for students that they might not normally see.
Greenhouses are always a great source
of pests and diseases.
Trips to look at problems in the field are essential for many situations – though
photographs can be emailed. Left: Ash tree dying back due to prolonged drought. Right: Soil
disease of English daisy, a laboratory test is required for a positive identification.
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