Horrors in the Garden: Hazardous Plants - Lee Valley Tools

Horrors in the Garden: Hazardous PlantsGardening NewsletterVol. 7, Issue 7 - October 2012Editor’s note: The following is meant as general information only and should notbe used as a substitute for professional medical advice.Prickly burdocks are a foe to shaggy dogs and fleece-clad hikers alike.After doing some weeding in a little country church garden this summer, Irediscovered the dark side of gardening. Absentmindedly, I had left my gardeninggloves at home — a dreadful error. A few nights later, a creeping, insidiousitch crept down my neck and back. Soon after, red, oozing blisters broke out andspread across my body. The walk-in clinic doctor diagnosed a bad case of poisonivy. The effect was, well, a bit of a horror show, at least until the medication tookeffect.Even experienced gardeners sometimes fall prey to plants that can cause pain,misery and, although rare, even death. Some are native species; others, nonnative.Each year, people, often children, and sometimes pets are poisoned orotherwise harmed from toxic berries, bulbs, leaves and other plant parts.Of course, most plants are beneficial and perfectly benign, but hazardous plants,though much fewer in number, are found everywhere. They grow on countryproperties or in woods near swamps and streams. Sometimes, they are foundon abandoned lots in cities and suburbs. They can even be found in our yardsand homes. Readers, take heed: wear gloves, don’t eat strange berries, educateyour kids and remove hazardous plants that are a risk to you and your pets. Hereare 10 common ones to avoid.1/5 www.leevalley.com

Horrors in the Garden: Hazardous PlantsGardening NewsletterVol. 7, Issue 7 - October 20121. Stinging Nettle (Urtica dioica):This quick-growing perennial is oftenfound in orchards, untended pastures,farmyards, ditches and waste places.I discovered it a few years ago whilegardening in an old farmyard. Contactcauses a painful sting from the tiny,needle-like hairs on the stem, leaf andflower. This is followed by prolongednumbness and itching that may last afew minutes or even a few days if thereis repeat contact. While rarely serious,the sting can be nasty.2. Giant Hogweed(Heracleum mantegazzianum):This enormous plant, also called giant The aptly named stinging nettlecow parsnip, is native to Asia. It wasintroduced to North America as an ornamental garden plant with no knowndiseases or insect pests. It has become an invasive species that can grow tomore than 16’ (5m) tall. It has white, umbrella-shaped flowers and large leavesthat can span 3’ (1m) across. The plant is often found along footpaths andriverbanks, and sometimes finds its way into a backyard garden.The sap from this plant can cause severe, painful burns and can also make yourskin sensitive to sunlight. If the sap comes into contact with someone’s eyes, itcan lead to temporary or permanent blindness.3. Ragweed (Ambrosia spp.):This is considered the number onecause of hay fever, in part becauseof its abundance and the fact that itflowers all summer long. You find italong driveways, roads, sidewalksand cultivated fields. It tends to growwhere soil has been disturbed (anotherargument for mulching).Allergy sufferers should steer clear ofthis roadside ragweed2/5 www.leevalley.com

Horrors in the Garden: Hazardous PlantsGardening NewsletterVol. 7, Issue 7 - October 2012While there are dozens of varieties, the two that are mainly responsible for thesneezing, runny nose and itchy eyes, mouth and throat are common ragweed(A. artemisiifolia) and giant ragweed (A. trifida). Common ragweed grows toabout 5’ (1.5m). It has long, deeply toothed divisions in each leaf, and spikesof small, numerous, greenish yellow florets. Giant ragweed grows as tall as 14’(4m). Both varieties begin flowering in June and release their pollen in July.Only frost will kill this plant, so the pollen continues until then. It thrives in hot,dry summer weather. Those who suffer from a ragweed allergy would do best toavoid the outdoors during the middle of the day when pollen counts tend to bethe highest.4. Climbing Nightshade (Solanum dulcamara):Also known as bittersweet, it’s native to Europe but has quickly become a weedin North America. It is both a climbing vine and an erect herb. All parts of theplant are poisonous, but it is often the berries that are mistaken for edible fruit.Consumption brings on intense thirst, nausea, hallucinations, fever and highblood pressure. Its white or purple flowers resemble those of the potato ortomato, to which it is related. The plant flourishes in dark, shady spots, producingpointed, oval-shaped leaves and tubular flowers.5. White Snakeroot(Eupatorium rugosum):This tall native North American plant,with its showy clusters of small, brightwhiteflowers, is easy to spot growingin fields, woods, thickets, lake edges,waste places and other shady areas.It grows best in basic soil but preferswet soil.The leaves and stems of the plantcontain an extremely dangerouspoison called tremetol. When animalseat it, they develop a condition calledthe trembles that may cause death.The meat and milk of such animalscan contain tremetol at levels toxic tohumans. Fortunately, this condition israre nowadays because of moderndayfarming practices.White snakeroot is a danger to grazinganimals such as cows and sheep.3/5 www.leevalley.com

Horrors in the Garden: Hazardous PlantsGardening NewsletterVol. 7, Issue 7 - October 20126. Rhubarb (Rheum rhabarbarum):A spring ritual for many gardeners is topick fresh rhubarb from the garden anduse the stalks to make tasty sauces,pies and crumbles; however, the large,coarse leaves are toxic. Consumingthem can cause nausea, vomiting,burning in the mouth and throat,abdominal cramping and diarrhea.7. Burdock (Arctium spp.):This weed’s purple, rounded flowerheads have hooks that attach toclothing, hair and animal fur. Brushingup against them can result in severalhours of serious grooming, especiallyif you happen to be walking a shaggydog. When pets try to remove the pricklyseeds themselves, they can irritateEnjoy rhubarb stems in baked goods, butbe sure to avoid eating the leaves.their skin. If they consume them while doing so, it can cause intestinal hairballs.Interestingly, burdocks were the source of inspiration for Velcro®, the fabricfastener.8. Buttercup (Ranunculus spp.):A favorite childhood game was to press a wild yellow buttercup to the skin justunder the chin to test if you liked butter. A slight redness was supposed to be thesign of a butter lover. In reality, both buttercups, as well as the popular gardenvine clematis (also part of the buttercup family), contain a severe skin irritantcalled glycoside. Physical contact with the leaves and flowers can cause irritationand blistering. Consumption, which is usually deterred by their strong, unpleasantflavor, can cause intense burning of the mouth and digestive tract. Gardenersshould wear gloves when weeding buttercups or when planting clematis.9. Jack-in-the-Pulpit (Arisaema triphyllum):This is an unusual-looking wildflower, with a green and white hood shaped likea pulpit. It produces clusters of red berries, which can be especially attractive tochildren drawn to its showy flowers and foliage. If the berries are eaten, symptomsinclude a painful burning in the mouth and throat, swelling and choking. If largeamounts are consumed, convulsions, coma and death can result.4/5 www.leevalley.com

Horrors in the Garden: Hazardous PlantsGardening NewsletterVol. 7, Issue 7 - October 2012The attractive red berries of Jack-in-the-pulpit pose a serious health danger if eaten.10. Poison Ivy (Toxicodendron radicans):This woody plant causes countless cases of contact dermatitis in humans.“Leaves of three, let them be” is the common warning. The toxin, calledurushiol, is easily spread, especially if you scratch the affected areas or comeinto contact with previously contaminated clothing. Fortunately, the rash doesnot spread from one person to another. Poison ivy is most dangerous whenburned, as the poison rises in tiny drops in the smoke and ashes. Breathingthis smoke can cause severe damage to the lungs and even death.These are just a few of the plants to heed while enjoying the cool crisp days ofautumn. Remember, winter relief is just around the corner!Text and photos by Julianne LabrecheJulianne Labreche is a freelance writer and gardening enthusiast who volunteerswith Master Gardeners of Ottawa-Carleton.5/5 www.leevalley.com