Michigan State University Extension
Ornamental Plants plus Version 3.0 - 00000307
11/12/99
CATTLEYA INSECT PROBLEMS
The orchid weevil is about 1/8 inch long, smooth, and
shiny black. The larva is a white legless grub about 1/16
inch long. The larva feeds on the new roots, hollowing
out the inside. The tips of infested roots turn black.
The adult feeds on the roots and tender young leaves,
sheaths and bulbs. The adult may feed on flower petals
before they open. Injury caused by the insect may be
entrances for diseases.
The cattleya weevil adults are less than 1/2 inch long
with white marks on the back. These feed on the surface
of pseudobulbs and puncture the leaf surfaces. The larvae
feed on the leaves and develop on stems and pseudobulbs.
The injury allows for the entrance of decays. Infested
plants fail to bloom.
Thrips cause browning and blotching of the leaves and
blasting of flower buds. The leaves and flowers will have
a silvery appearance, then turn brown.
Slugs feed on buds, blossoms, leaves, and tender stems.
Aphids suck plant juices and are usually found at the stem
tips. A heavy infestation will coat the leaves with
sticky honeydew. A black, sooty mold can grow on the
honeydew. The insects can be green, white, pink or black.
Scales are usually brown, hard shells attached to the
stems or undersides of the leaves. Sprays are not
effective since the shell protects the insects. Heavily
infested plants should be discarded. Physically removing
the scales and then controlling immature stages with
sprays may control the problem on lightly infested plants.
Related information.
Pesticide Recommendations
This information is for educational purposes only. References
to commercial products or trade names does not imply
endorsement by MSU Extension or bias against those not
mentioned. This information becomes public property upon
publication and may be printed verbatim with credit to MSU
Extension. Reprinting cannot be used to endorse or advertise
a commercial product or company.
This file was generated from data base ZZ on 01/19/00.
Data base ZZ was last revised on 11/12/99.
For more information about this data base or its contents please contact
heatley@msue.msu.edu . Please read our
disclaimer for important
information about using our site.