I think everyone knows the tiny black flies, about 2-3 mm (1-1.5 inches)
when cultivating carnivorous plants. They are often prey for Drosera
and Pinguicula, caught by their sticky glands. Unfortunately these
flies of the genus Sciara ssp. or Lycosia ssp. (I believe in English
they are called sciarid flies, aren't they?) produce larvae which live
in moist soil, attacking the roots of plants. They also can kill small
seedlings or small plants out of leave cuttings if there are several
larvae attacking the plant. If the plants aren't killed completely by
the larvae the lesions are often point of penetration for fungi. I lost
several times plants due to larvae attack. I know that a biological
means to kill the larvae is to infect the soil with nematodes
(Steinernema), which kill the larvae. This is a efficient method, but
quite expensive. I have read that you can also use insecticides with
the active substances "Permethrine" or "Deltamethrine". Does anyone
have experience with the use of these insecticides in Pinguicula? Are
there other methods to control the larvae?
Generally I have a request to everybody who talks about fongicides or
insecticides: Please use the name for the active substances, because the
name of the products vary from country to country, but the active
substances are scientific and are used worldwide.
Oliver
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Oliver Gluch
Lindenallee 44
26122 Oldenburg
eMail: Oliver.Gluch@t-online.de