PESTS & DISEASES
Red Lily Beetle
The red lily beetle devours the leaves, stems, buds and flowers of lilies, fritillaries and all plants in the Liliaceae family. It has a rectangular body shape 6 to 8 mm. in length. The orange lily beetle eggs are found on the undersides of the leaves. The larvae, once hatched from the eggs, look much like small slimy black globs. In reality the larva covers itself with its own excrement in hopes of not being appetizing to its predators.
The methods to control red lily beetles: hand pick and destroy each beetle, all the eggs and the larvae. Always check leaf undersides for the hiding eggs and destroy by rubbing them off. The adults can be sprayed with any pyrethrum-based insecticide or any other registered pesticide. Buy a concentrated pyrethrum liquid and mix to 0.5% strength. Rotenone may also be used and effective. Use all products safely and with care following instructions.
In the spring and fall clean up any debris (leaves, mulches etc.) under these plants as the red lily beetle likes to hide and overwinter under such materials. Also, in spring and fall stir up the soil under these plants as the beetle likes to also bury just under the soil surface.
Always BE VIGILANT!! And all summer keep looking as the different stages occur and as the red lily beetle is a strong flyer it may come in from neighbouring locations.
Emerald Ash Borer – a very enlightening and hopeful article on the attack on Manitoba Ash trees. Read here.
These insects are the nymphs of the predatory stink bug Apoecilus. There are numerous varieties of stink bugs. Some, like the Apoecilus, are beneficial, eating garden pest insects. Other varieties of stink bugs are garden pests that feed on fruit.
The Apoecilus nymphs can be mistaken for the more serious nymph of the brown-marmorated stink bug which is a nasty pest for many garden and fruit crops. Early feeding on apple crops can cause catfacing, while on strawberries and haskaps they cause fruit drop and bud death. The brown-marmorated stink bug is one of the most recent exotic pests that has arrived in Manitoba and could increase in numbers as our climate warms.
More info:
Apoecilus Nymphs
Brown Marmorated Stink Bug Nymphs
Forest Tent Caterpillar
The forest tent caterpillar egg rings around branches house approximately 300 eggs. Removing them through scratching off, being vigilant to not damage the bark, or pruning the branch with the egg rings on it, are excellent methods to control the worms before hatching. This should be done anytime one notices the ‘rings’ present. They are most noticeable when the leaves are off the trees/shrubs. Following is an excellent article from the University of Saskatchewan about forest tent caterpillars: Forest Tent Caterpillar
Mealy Bug
– appears as white fluffy areas around stems and leaf nodes especially on newer growth.
– related to scale insects as they survive by sucking on the plants juices/sap and they protect themselves by the fuzzy fluff which acts as a protective coating.
– the white ‘fluff’ is a waxy coating which resists water.
– to eliminate mealy bugs rubbing alcohol needs to be applied to these areas with either a cotton-tipped stick, cotton ball or from a spray bottle.
– if the mealy bug is not eliminated, overtime leaves will yellow, dry and drop off. Hence, no chlorophyll produced to support the plant. With severe infestation recommendation is to dispose of the plant.
– when the infestation is extreme the honeydew excretions from the bugs will drop and collect on leaves and cause sooty mould to form.
Black Knot Disease
Shubert chokecherry trees, plum trees, wild chokecherry and pincherry trees are susceptible to this disease. Early stages will show the black swollen growths on the branches and twigs. These must be removed a minimum of eighteen inches from the ‘knot’ towards the tree trunk and the pruners sterilized with each cut. The necessity of removing these are that the spores are formed in these growths. If left on the tree the spores will continue to infect trees of this variety. Once there are signs of infection in the trunk, which is manifested by cracking or splits, the tree will not survive and should be removed. Another such specimen should not be planted in that area or surrounding as the spores have a possibility of remaining in the soil and remaining roots.
Impatiens Downy Mildew has Arrived in Manitoba!!
If any of your Impatiens walleriana have the traits of the above picture,
for more information: http://www.mgmanitoba.com/ask-an-mg/
Spotted Winged Drosophila

The Spotted Winged Drosophila (Drosophila suzukii) (SWD) is a vinegar fly of East Asian origin that can cause damage to many soft-skinned fruit crops. SWD pierces seemingly healthy fruit, and lays its eggs. The eggs hatch in about 3 days, the larvae feed on the fruit and emerge as adults after 6-28 days. Early detection is critical because symptoms often do not appear until after the fruit is harvested. Commonly confused with the common fruit fly, Drosophila melanogaster, SWD differs as it attacks unripe to ripe fruit, whereas the common fruit fly feeds on overripe and rotting fruit.
SWD most commonly afftects raspberries, strawberries, blueberries, cherries and plums. It was first identified in Manitoba in commercial berry fields in August 2013.
For continued updated information on SWD follow this link:
www.gov.mb.ca/agriculture/crops/insects/spotted-winged-drosophila.html
Ladybug Larvae eating Aphids.
An example of healthy biodiversity in the garden. This is a major reason to acquaint oneself with lady bug larvae and not destroy them.
Fall Webworm
This is an example of the fall webworm which appears in late summer or fall and how it manifests on common trees. The fall webworm is a tent caterpillar much as the forest tent caterpillar is. The most effective way of eradicating this worm is to prune off all affected branches from your tree or shrub and throw it into the trash. If the branches are too high to prune hose the web with strong water pressure so as to break up the webbing and making the worms accessible to foraging birds.
Poison Ivy – in Autumn foliage