Rose sawflies adults are small primitive wasps who’s larvae look like tiny little caterpillars. These larvae, commonly called rose slugs, are voracious feeders and feed almost exclusively on rose leaves. If their numbers are high enough they can quickly defoliate an entire rose bush. Larvae feeding damage appears as skeletonized leaves that look like window panes. As the feeding continues large holes are chewed through … Continue reading Rose Sawflies
Several Honey Locust trees here in Southern Ontario have been the target of small green bugs that have been distorting honey locust leaves and, in some cases, partially defoliating these trees. The main culprit has been the honey locust plant bug (Diaphnocoris Chlorionis). The honey locust plant bug (Diaphnocoris chlorionis) are approximately 3mm (1/8 inch) long when full grown and light green in colour. They pierce leaf … Continue reading Honey Locust Plant Bug Damage And Control
June is my favorite month in the garden. So many perennials and flowering shrubs are blooming and the annuals are beginning to fill out a bit. The landscape is alive with colour and the air is full of a bouquet wonderful fragrances. The temperatures are warming up but but usually still remain comfortable. There is still a lot of work to do in the gardens … Continue reading Ornamental Garden Calendar For June
Red Bark Phenomenon is a fairly new occurrence here in North America. Scientists, horticulturalists and the like have been scrambling to learn more about this phenomenon as more and more trees are becoming affected. What they have learned so far is that the reddening of the bark is caused by a microscopic, filamentous green algae (Chlorophyta), that is believed to belong to the genus Trentepohlia. The … Continue reading Red Bark Phenomenon
Hydrangea leaf-tiers (Exartema ferriferanum), are a small moth whose larvae, (a tiny green caterpillar with a black head), sew terminal leaves together with a silk thread. Once inside this enclosure they feed on the leaves and flower head. These leaf enclosures become wrinkled and puckered and are easy to spot on the plant. They are native to Canada and U.S.A with the majority of sightings … Continue reading Hydrangea Problems…Leaf-tiers
Dog vomit slime mold is an interesting occurrence in the garden and in the wild. A yellowish blob seems to appear almost overnight that looks very much like an animal has thrown-up in the yard. The cause of this blob is actually a slime mold, Fuligo septica. Fuligo septica are eukaryotic organisms from the Protista kingdom. These decomposers feed on the fungi, mold and bacteria … Continue reading Dog Vomit Slime Mold in Wood Mulch
Birds nest fungi are are a rather interesting looking fungi. They appear like tiny birds nests filled with eggs. The fungi responsible for this anomaly are a family of fungi called Nidulariaceae. There are 31 birds nest fungi in North America with 5 of them being fairly common. The colour and appearance of the nests and eggs can vary depending on the species of Nidulariaceae … Continue reading Birds Nest Fungi In Wood Mulch
HEALTHY SOIL: Is probably the single most important factor contributing to the health of all vegetation. If you do nothing else for your garden than to improve its soil it will be time and money well invested. Lets take a look at some of the components that affect soil health. Soil Texture Soil is comprised of different sizes of mineral particles. The relative amounts of … Continue reading Healthy Soil
The gardens here in Ontario are awakening from their winter slumber. Spring is a time of vigorous, active growth for both desirable and undesirable plants. Winter annual weeds are in full force and many of them have already started flowering. The perennial weeds are likewise coming into full force. Now is the most important time to get a handle on your weed populations. Putting the … Continue reading 20 Common Spring Weeds in Ontario
Boxwood leafminers (Monoarthropalpus flavus syn. Monarthropalpus buxi) are orangish gnat like flies that are a major pest of boxwood. Their larvae, which are small worm like maggots, feed inside of boxwood leaves causing blisters and puckering on the backside of the leaf and brown blotching on the upper surface. Premature defoliation of infected leaves occurs. In large numbers they can cause extensive and unsightly damage even … Continue reading Boxwood Leaf Miners
What is Coral Spot Nectria Canker? Coral Spot Nectria Canker is a fungal disease caused by the fungus Nectria cinnabarina. These opportunistic fungi typically attack trees and shrubs that have been weakened by stress or injuries like mechanical injury, storm damage, insect feeding, animal damage, pruning, disease, frost cracks, cold injury or drought damage. Once the fungi gain entry to the plant they cause the … Continue reading Japanese Maple Problems…Coral Spot Nectria Canker
Red twig dogwood species consisting of Cornus sericea, Cornus alba and Cornus sanguinea are prone to several fungal diseases and their coresponding fungi including powdery mildew (Erysiphe pulchra), dogwood anthracnose (Discula destructiva), leaf spot (Cercospora cornicola and Septoria) and Botryosphaeria canker (Botryosphaeria dothidea). Of these fungal diseases, Botryosphaeria canker and dogwood anthracnose are both capable of producing cankers on the stems of dogwood. To tell … Continue reading Botryosphaeria Canker of Red Twig Dogwood
Galls are abnormal growths that can appear on roots, stems, trunks or leaves. There are many woody plants that get galls and there are several different gall makers (causes for the gall formation); insects, mites, bacteria, fungi, or nematodes. The galls formed are unique to the gall maker and the genus or species it feeds on. For crown gall the disease is caused by a … Continue reading Crown Gall on Euonymus
Pine needle scale (Chionaspis pinifoliae) are very small, white, stationary insects found on the needles of pine (primarily ponderosa, Mugo and scotch), spruce and occasionally, balsam fir, hemlock, and yew. They feed by inserting their stylet into the needles and sucking the juices out. This causes spotting to the branches. Badly infested trees may have a greyish appearance with needle loss. Left uncontrolled whole branches … Continue reading Pine Needle Scale: Identification, Life Cycle and Control
Pacific Poison Oak (Toxicodendron diversilobum) and Atlantic Poison Oak (Toxicodendron Toxicodendron pubescens) are the only two poisonous to touch plants in this series that do not grow in Canada except for the very south/western tip of British Columbia. They are not nearly as prevalent as poison ivy with Pacific poison oak occurring natively along the pacific coast of the U.S. and Atlantic poison oak occurring … Continue reading Poisonous to Touch Weed Series: Poison Oak (Toxicodendron diversilobum) and (Toxicodendron pubescens)
Poison Sumac (Toxicodendron vernix) is a perennial shrub or small tree, native to eastern Canada as well as east-central and eastern United States. Like poison ivy and poison oak the leaves and berries of this plant contain urushiol (an oily mixture of organic chemical compounds); but the oil is said to be more concentrated in poison sumac. The Urushiol can cause a severe allergic reaction in sensitive … Continue reading Poisonous to Touch Weed Series: Poison Sumac (Toxicodendron vernix)
Wild parsnip (Pastinaca sativa) aka poisonous parsnip is one of the phototoxic weeds we grow here in Canada. It is a non-native and as such is an aggressive and invasive species. It is the only one of the phototoxic weeds that has a yellow flower, the others bearing white umbels. It’s pinnately compound leaves are also quite different than the palmately compound leaves of cow … Continue reading Poisonous to Touch Weed Series: Wild Parsnip (Pastinaca sativa)
Cow Parsnip (Heracleum maximum) aka Common Parsnip or American Parsnip, is a native plant that widely grows in north America. It is a large plant rising up to heights of 1-2.5 m (3-8 ft.) when in flower. Like giant hogweed, cow parsnip contains organic chemicals within it’s sap called furanocoumarins. This chemical is activated by ultraviolet radiation and the result is severe burning, blistering and … Continue reading Poisonous to Touch Weed Series: Cow Parsnip (Heracleum maximum)
Giant hogweed (Heracleum mantegazzianum) is likely the largest and most dangerous to touch perennial weed in North America. In Ontario it commonly reaches heights of 3-4.5m but in other parts of the world it can reach heights of 5.5m (MacDonald F. and Anderson H. 2012). There are a few other Giant Hogweed species that are a bit smaller in size but Heracleum mantegazzianum is the … Continue reading Poisonous to Touch Weed Series: Giant Hogweed (Heracleum mantegazzianum)
By: Kimberley Pacholko Eastern Poison Ivy, (Toxicodendron radicans) and Western Poison Ivy (Toxicodendron Rydbergii ) are important plants to learn how to identify for personal safety. Touching any part of this plant can cause a painful itchy rash with red swollen skin and painful blisters. I have had the miss fortune of being caught twice by this plant and can testify to how unpleasant the … Continue reading Poisonous to Touch Weed Series: Poison Ivy (Toxicodendron radicans and Toxicodendron Rydbergii)
Horticulture For Home Gardeners 