Mealy Bugs and Stagnospora

J.E. Shields
Mon, 17 Mar 2003 05:19:05 PST
Dear all,

I strongly endorse John's recommendation of Marathon for treating mealy bug 
and other insect infestations on bulbs, especially on container-grown 
plants.  We use it all the time to prevent new infestations here.  Most 
outdoor-grown plants we receive here have a few mealy bugs on them when 
they arrive.  We use Marathon to kill these and avoid the spread of a 
noxious pest of bulbs.

My web site often attracts questions about treating Stagnospora.  It can 
infect Crinums and Clivias as well as Hippeastrum, Hymenocallis, and 
probably almost all Amaryllidaceae.

For individual bulbs, I recommend the following procedures:

1. Physically remove the worst of the red incrustations and affected plant 
2. Dip or spray the bulb and infected leaves with diluted hydrogen peroxide 
(final concentration about 1% H2O2 in water) -- drugstore peroxide is 3%, 
so dilute one part drugstore hydrogen peroxide with two parts water
3.  Let dry in air for a day or two
4.  Spray with a good systemic fungicide.  I use Bonomyl/Cleary 3336 
wettable powder (thiophanate methyl) but benlate (benomyl) is good if you 
can find it
5. Repeat the spraying with systemic fungicide at about 10-day intervals 
until you are satisfied that the danger of re-infection is past.

Stagnospora infections almost always result from excessive water and 
humidity.  Control the moisture and you can avoid a lot of the potential 
stagnospora infections.

Jim Shields
in central Indiana

At 06:51 AM 3/17/03 -0500, you wrote:
>Marathon (imidacloprid) is an excellent treatment - contact and systemic
>insecticide with residual activity that lasts  several months.  It is an
>ideal drench for bulbs a few weeks before they go dormant.
>Dr John T Lonsdale
>407 Edgewood Drive,
>Exton, Pennsylvania 19341,  USA

Jim Shields             USDA Zone 5             Shields Gardens, Ltd.
P.O. Box 92              WWW:
Westfield, Indiana 46074, USA                   Tel. +1-317-896-3925

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