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COMMON BURDOCK (Arctium minus )

This familiar biennial weed is found growing in waste places and along roadsides. It grows from a fleshy taproot and produces large, heart-shaped, hairy leaves and red-violet flower heads surrounded by numerous hooked bracts that form a bur-like cup. Burdock is often confused with cocklebur (a far more dangerous plant). Burdock burs are rounder and have softer, more Velcro-like hairs than cocklebur. Cocklebur burs are oblong and have hooked spines on the bur, and have, on the end of the bur, two spines which are larger and not as strongly hooked.

Means of Annoyance
The burs of this plant may lodge in the skin, eyes, ears, mouth, throat, or stomachs of grazing animals. Direct irritation may result, with swelling and pain, or the bur may form the center of a "hairball", a mass of plant matter, hair, and debris that can cause digestive tract irritation and possible obstruction. These burs also tend to lodge in the fur, manes, and tails of animals.

CLOVER(from the Trifolium family)

The three main types of clover are, red clover, white clover and alsike clover. Clover is a many-stemmed herb. Its leaves are made up of 3 leaflets grouped at the ends of the long leafstalks. There are no crescents in the leaflets. Its flowers, borne in rather compact, stalked heads, range from red to white, depending on the type of clover

Means of Annoyance
Clovers may contain oestrogens, cyanogenic glycosides, goitrogens, nitrates and other substances. Also known as Dew-poisoning or trifoliosis, all the green parts of clover become poisonous when dampened by dew. There are also diseases which may be caused by fungi which infect the clover. It is not a commonly reported toxicity, and is not usually serious even if toxicity occurs. It is not known if the wet clover causes problems by contact or ingestion. The symptoms include gastrointestinal distress, including mild colic and diarrhoea. Bloating can occur if the animal is no accustomed to eating the lush clover. Photodermatitis ("sunburn") is also possible, especially on the parts of the body that contact the wet grass (lower legs, mouth). Liver damage has been suggested, but not well-verified. In rare cases, the sunburn may spread to the entire body, especially in lightly pigmented areas, but large amounts must be consumed before serious body-wide sunscald develops.

FOXTAILS (Setaria spp.)

The photos above are that of a foxtail. Not the standard flower variety some know as foxtails, but a weed type plant that is very dangerous to animals, not just dogs.

Means of Annoyance
In the dried stages, the bristles become larger and more rigid. They face only one way. As such they can invade the body through any orifice, the skin, the feet, etc. Once a penetration has taken place, the foxtail, through it's design, can move forward into the body, helped along by the body's movement. Once the foxtail has entered the body, it can travel great distances through the blood stream. There are cases on record of foxtails being found in the heart, after death and autopsy. Entry points can be in the pad or paw and end up in the heart. Along the way massive infections can occur at the points of entry and any place lodging takes place in the body. They are designed to move in only one direction. Even if discovered prior to full entry, they are to say-the-least devils to extricate. You must be sure that you have removed all of the foxtail from the point of entry. If you have the slightest doubt, that you have left anything behind, you must take your animal to a veterinarian to check it out. They can become lodged in the hair, ears, and any other location. If your animal runs lose or in a yard where they may have come in contact with them, thoroughly comb and brush them out, and inspect down to the skin all over, between the pads, in the ears, and up the nose. If your animal is sneezing when they return from a run, check the nose with a flashlight all the way back, and if you can't find anything, get them to a veterinarian. Get them there, if you find something and can't remove it also. Time is of the essence. The plant can only be removed by physically cutting and throwing them away. Unfortunately their seeds are already in the ground and waiting for the next season to sprout and start all over again. Cutting or plowing them into the ground only distributes more seeds for next year. Deal with them as best you can for the season that is upon you, and do not disturb them by weed whacking and sending the seeds to other parts of your yard for next years cycle.

GIANT HOGWEED (Heracleum mantegazzianum)

Giant Hogweed is originally from Asia and was introduced as an ornamental. A member of the parsley family, its most impressive characteristic is its massive size. It reaches a height of 10 to 15 feet when in flower and has hollow stems, 2 to 4 inches in diameter with dark reddish-purple spots and bristles. Coarse white hairs at the base of the leaf stalk are also purplish, and each purple spot surrounds a blister-based hair. The deeply incised compound leaves grow up to 5 feet in width. Giant hogweed flowers mid-May through July, with numerous white flowers clustered in an umbrella-shaped head that is up to 2.5 feet in diameter across its flat top. The plant produces flattened, 3/8-inch long, oval dry fruits that have a broadly rounded base, and broad marginal ridges. Hogweed prefers moist soil and can quickly dominate ravines and stream banks.

Means of Annoyance
Giant hogweed produces severe, painful, burning blisters in susceptible people, the symptoms appearing within 24 to 48 hours after contact. The sap can produce painless red blotches that later blacken and scar the skin for several years. For an adverse reaction to occur the skin, contaminated with plant juices, must be moist and subsequently exposed to sunlight (see also Lantana and Hypericum). This phenomenon, known as phytophotosensitization, occurs in animals when chemical compounds, either derived directly from plants or produced by the animal in response to plant substances, are present in peripheral circulation.

JACK-IN-THE-PULPIT(Arisaema triphyllum)

These herbaceous perennials pop up in spring. They grow 1 to 2 feet tall from a tuberous root. The large leaves are three-parted, smooth-margined, and net-veined. Each plant produces one bloom beneath the leaves on a short stalk. The "jack" is a fleshy green spike ("spadix") bearing a number of inconspicuous male and female flowers. The most noticeable part of the bloom is the "pulpit", a modified leaf ("spathe") that wraps around and hides the spadix. It may be all green or striped with red or reddish-violet. In late summer the spathe falls away, revealing a cluster of bright red berries.

Means of Annoyance
Rarely is enough of this plant consumed to cause a problem, but the potential exists, especially in spring when other forages are not readily available and if the livestock have access to a wooded area. Signs are self-limiting, and a veterinarian only needs to be contacted if signs do not resolve or if breathing is affected. The bulbs, stems and possibly leaves are dangerous causing Oral and gastric irritation, mouth and throat swelling on rare occasions may be severe enough to affect breathing.

POISON IVY (Toxicodendron radicans)

A native plant that is found throughout Ohio, on roadsides, forest edges, and waste areas. Poison ivy is a creeping perennial vine or bush that reproduces by seed and vegetatively by roots. Woody stems grow along the ground and can climb on a permanent structure (e.g., walls, trees, utility poles, or fenceposts). Once it begins to climb, adventitious roots appear from the stem that hold it in place, giving the stem a fuzzy appearance. The leaves of poison ivy are alternate, with three leaflets, and often shiny with a reddish hue. The shape of the leaflets can be variable (elliptic to egg-shaped), as can the amount and position of hairs. Leaf margins may be either smooth, toothed, or lobed. The green-yellow-white flowers have five petals and bloom in June and July. The small white berries (about one-eighth inch in diameter) are round and hard.

Means of Annoyance
All parts of this plant contain an oily resin (3-pentadecylcatechol) that can cause allergic reactions. Virtually anything that comes in contact with the oily resin (e.g., animals, clothes, gloves, tools) can carry the resin and cause dermatitis. Smoke of burning poison ivy plants can be extremely dangerous.

STINGING NETTLE (Urtica dioica)

A bristly, stinging, erect perennial that reproduces by seeds and creeping rootstocks. Stems and leaves are covered with numerous stinging hairs, the sting resembling that of a bee. Plants grow up to six feet in height, with slender, rigid stems branching mostly at the top. Leaves are opposite, three- to six-inches long, pointed with saw-toothed margins, sometimes rounded at the base. Flowers are green to white and arranged on branched spikes arising from leaf axils. The plant is found throughout Ohio, especially along roadsides, fencerows, ditchbanks, shady or moist wood edges.

Means of Annoyance
Contact with the plant can cause inflammation and welts may form.


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