One of the noxious weeds that I see everyday when I walk my child to school is the Yellow Starthistle. The flowers may look innocent but the Yellow Starthisle is registered in the list of noxious weeds in California. Its aggressive spread affects the yield and quality of rangelands, pastures and grasslands. The spines on the flowers make it less palatable to livestock; hence they avoid areas that are infested with the weed. In this case the spread of Yellow Starthistle does not affect livestock per se but it reduces the effective grazing area."Noxious weed: any living stage (including seeds and reproductive parts) of a parasitic or other plant of a kind which is of foreign origin, is new to or not widely prevalent in the U.S., and can directly or indirectly injure crops, other useful plants, livestock, poultry or other interests of agriculture, including irrigation, navigation, fish and wildlife resources, or the public health." ~Federal Noxious Weed Act 1974
For the horses, however, this weed is food. Horses eat this weed and they are capable of chewing and digesting it. When a horse consumes a certain amount of this toxic weed, it can contract a neurological disorder called "chewing diseases" (Nigropallidal encephalomalacia). Inability to swallow and chewing in the absence of food in the mouth are among the symptoms of the disease.
This weed is wanted in California! You and I are licensed to kill it. If you are looking for an opportunity to have no mercy on a plant - this is it!
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