Poison ivy (Toxicodendron radicans; formerly Rhus radicans) is a North American plant, well known for its sap that causes an itching rash. Old saying: "Leaves of Three, Let Them Be!" The three common forms are:
trailing/creeping ground cover/vine, 10-25 cm tall
shrub up to 1.2 m tall
The deciduous leaves of poison ivy are trifoliate with three almond-shaped leaflets. Leaf colour ranges from rusty brown (when first unfurling in early spring), light green (the younger leaves), dark green (mature leaves), and turning bright red in fall. The milky sap of poison ivy darkens after exposure to the air. Read more about and see more pictures of poison ivy at the websites listed below.
Giant Hogweed [Heracleum mantegazzianum] is a dangerous plant that looks a bit like Queen Anne's Lace. In it's second year it grows over 2 metres, and produces large flower umbels [umbel - from Latin umbella a sunshade, from umbra shade; flat-topped or rounded inflorescence characteristic of the family Umbelliferae in which the individual flower stalks arise from about the same point] like an umbrella. The sap from this plant can sensitize the skin to UV rays causing blisters and discoloured patches, blindness can result if the eyes are touched. Note that there are other species that are similar to Giant Hogweed such as Cow Parsnip and Purple Angelica. Check the comparison chart from the Invasive Plant Atlas of New England (University of Connecticut).
Angel's Trumpet: a large, dramatic, pendulous trumpet-shaped flower, 14 to 50 cm long and 10 to 35 cm across at the wide end. They are white, yellow, pink, orange or red, and have a delicate, attractive scent overtones, most noticeable in early evening. Flowers may be single or double. (Datura sp.): Poisonous and causes hallucinations. Government of Canada | Google Images | Datura, Wikepedia
Blackberry (Bramble family): raspberries, blackberries, dewberries, etc.
Dog Strangling Vine: This is a recent, undesireable vine. found along the Thames River in St Marys. It is a creeping invasive species of the milkweed family, the flower yielding a large number of seeds. It will thrive in shade, sun and all soil conditions, spread rapidly, reduce or eliminate other plants, and is extremely difficult to control. If you encounter any of these noxious weeds along the trail, please notify the trail organization.
Herb Robert: It is also known as Robert Geranium, is a common species of cranesbill. It produces small, pink, five-petalled flowers (about 1 cm in diameter) from April until the autumn. The leaves are fern-like, and the stems often reddish; the leaves too turn red at the end of the flowering season. In traditional herbalism, Herb Robert is used as a remedy for toothache and nosebleeds. It is also used on wounds for healing and to prevent scarring, having both an antiseptic and a styptic effect. Freshly picked leaves have an odour resembling burning tires when crushed, and if they are rubbed on the body the smell is said to repel mosquitoes and people.
Stinging Nettle: common herbaceous perennial flowering plant, native to North America. It has a flavour similar to spinach when cooked, and is rich in vitamins A, C, D, iron, potassium, manganese, and calcium. Don't touch nettles without gloves. Example - stinging nettle (Urtica dioica). Google Images (Urtica dioica)| Google Images nettles plant ontario
White Mulberry: a short-lived, fast-growing, mulberry tree, which grows 10 to 20 m tall. The White Mulberry is scientifically notable for the rapid plant movement of the pollen release from its catkins. The flowers fire pollen into the air by rapidly releasing stored elastic energy in the stamens. The resulting movement is in excess of half the speed of sound, making it the fastest known movement in the plant kingdom.