Presentation on theme: "Weeds Weeds. Plant Body ShootShoot system = leaves + stem RootRoot system MeristemMeristem = cells that divide for life of plant, can give rise to all."— Presentation transcript:
Plant Body ShootShoot system = leaves + stem RootRoot system MeristemMeristem = cells that divide for life of plant, can give rise to all plant structures
Plant Body Blade PetioleLeaf = blade + petiole Functions Exposes surface to sunlight Major site of photosynthesis Conserves water Provides for gas exchange
Stem Functions Holds leaves up to light Transport of substances through vascular tissue Xylem conducts water and minerals Phloem transports sugar
Plant Body Root Functions Anchors plant in soil Takes up water and minerals from soil
1 Tree Tobacco Nicotiana glauca glauca = bluish-gray, referring to leaf color Leaves contain high levels of nicotene Introduced from South America by missionaries, from imported grain or on purpose…?
2 Cheeseweed Malva neglecta Seeds and leaves are edible. Seeds are shaped like rounds of cheese.
3Castor Bean Ricinus communis Ricin in seeds --used to kill a spy on London Bridge --recently discovered in the US mail --possible cancer treatment Oil from seeds has laxative and wound-healing properties.
4 Sweet fennel Foeniculum vulgare Petioles are eaten, like celery. Folkways medicine: Dried Leaves may repel fleas Priests spread on mission floors for fragrance
5 Scarlet Pimpernel Anagallis arvensis Folkways Medicine: May repel witches Poisonous to humans and livestock
6 Poison hemlock Comium maculatum Conin causes muscle paralysis, found in all parts of plant. Conin causes muscle paralysis, found in all parts of plant.
7 Filaree (Storksbill) Erodium Fruit shape is long and pointed –Filaree comes from the Spanish name for needle –Erodium refers to heron Young foliage is edible
8 Saltbush Atriplex canescens Large numbers of nutritious seeds, Used by native Americans for flour
9 Sweet clover Melilotus albus Enhances production of cumarin by molds Original source of heparin Important source of honey
10 Opium poppy Papaver somniferum Morphine and codeine from developing seed pods
11 California Poppy Eschscholtzia californica Young foliage is edible Roots used for toothache
12 White Goosefoot Chenopodium Young foliage and seeds are edible
13 Mexican Tea Chenopodium ambrosioides Folkways Medicine: Seeds act against intestinal worms. Dried plant is used as seasoning.
14 Horehound Marubium vulgare Member of the Mint family Flavoring in candy, cough drops, and beer Folkways Medicine: good for sore throats
15 California Mugwort Artemisia douglasiana Folkways medicine: Uses for intestinal, respiratory and skin ailments.
16 Jimson weed Datura meteloides All parts of plant have alkaloids like atropine. --medical use --religious observances by Native Americans --hallucinogen in the 60’s DANGEROUS! Recent hospitalizations and deaths reported in LA County. DANGEROUS! Recent hospitalizations and deaths reported in LA County.
17 Sea Fig Charpobrotus chilensis Edible fleshy fruit forms below the flower Helps to stabilize soil on hillsides or sand near ocean
18 Tumbleweed (Russian Thistle) Salsola tragus Noxious weed = targeted for eradication Shoot breaks off close to base and is pushed by wind to distribute seeds. Contains high levels of nitrates or soluble oxalates
19 New Zealand Spinach Tetragonia tetragonioides Leaves can be eaten raw or cooked Contains harmless levels soluble oxalates
20 Water Cress Rorippa nasturtium-aquaticum Leaves and shoots can be eaten. Rich in Vitamin C Be sure it comes from unpolluted waters!
21 Wild celery Apium graveolens Escaped from cultivation Petioles are eaten Wild plant has strong taste made milder by cooking
22 Chicory Cichorium intybus Root scrapings used as coffee flavoring or substitute Leaves of C. endiva used in salads
The pollen is a common respiratory or hay-fever allergen. 23 Western Ragweed Ambrosia
Young leaves are edible One species is a noxious weed 24 Sow Thistle Sonchus
25 Plantain Platago potagonica Young leaves are edibleYoung leaves are edible Folkways medicine: wound healing, laxativeFolkways medicine: wound healing, laxative
26 Curly Dock Rumex crispus Young leaves are edible Folkways medicine: to treat cough, blood pressure, itching, sprains Toxic to livestock
27 Dandelion Taraxacum officinale Young leaves and roots are eaten Dried roots used as coffee substitute Seeds dispersed by wind
28 Black Mustard Brassica nigra Young leaves are eatenYoung leaves are eaten Seed oil used to make mustardSeed oil used to make mustard Possibly introduced by missionaries who scattered it along the Camino Real to mark the way between missionsPossibly introduced by missionaries who scattered it along the Camino Real to mark the way between missions
29 Wild Radish Raphanus sativus Scrapings from young roots or young seed pods taste like radishes
30 Wild oats Avena fatua Escaped from cultivation Seeds are edible
31 English Ivy Hedera helix Juice causes skin irritation Berries and leaves are toxic
A related species provides treatments for Hodgkin’s disease, leukemia and other cancers 32 Periwinkle Vinca major
33 Garden Nastursium Tropaeolum majus Leaves are eaten in salads Hallucinogenic properties unproven
34 Blue Gum Eucalyptus Eucalyptus globosus Added as a flavoring to candies and cough medicines
35 Spurge Euphorbia Milky sap (latex) causes skin irritation Relative of the mildly-toxic Poinsettia plant
37 White and Purple Nightshade Solanum Berries are poisonous Relatives of the potato
Worksheet Complete page 169 from lab manualComplete page 169 from lab manual Be sure your instructor checks your completed worksheet before you leave the labBe sure your instructor checks your completed worksheet before you leave the lab