New Weeds to Watch For
Heads up weed watchers! The Hood River SWCD has received reports of several new weeds moving into the county and we need your help to keep an eye out for them. They are puncturevine and giant hogweed.
Puncturevine is a painful pest. It is a sprawling annual plant that forms a dense mat with very sharp, spiny seed heads. This nasty weed has infiltrated Hood River County from the east. Also known as goathead, puncturevine has branched stems that can spread up to 6 feet wide, stemming from a single crown. Flowers are small, yellow and have 5 petals. The leaves are hairy, 1-3 inches long, and divided into leaflets, each about 1/4 inch long. The seed head is woody with very sharp spines.
Seeds are easily spread by sticking into footwear, vehicle tires and animals. This plant poses serious problems for recreationalists and agriculturalists alike. The seeds can easily puncture a bike tire, inflatable raft or dog’s paw. Puncturevine has been found recently in area orchards where seeds are being spread by tractor tires and other farming activities. Plants are actively producing seeds now and will continue to do so until frost.
Puncturevine has been found throughout the county including the Hood River waterfront, Eastside Road, Lost Lake Road, Tucker Road and in the high school baseball fields, among other places. Thanks to many reports from diligent weed watchers, we’ve discovered that this plant is more widespread than originally thought. If you see it, the county needs your help to remove it. Please try to pull the entire taproot, gather all of the seeds, bag them and put it in the garbage for landfill disposal. This is one to nip in the bud!
Giant hogweed has been found at two sites in the county. It is a Class A noxious weed in Oregon which means that it is a high priority for eradication. It is a short-lived perennial and is often confused with more common carrot family plants such as cow parsnip, poison hemlock and wild carrot.
Giant hogweed can reach a mature height of 10-15 feet. The stem is often dark purple in color, but can vary from entirely purple to mostly green with purple blotches. The compound leaves are 3-5 feet and deeply incised. The flowers are large, white, umbel-shaped and up to 2 feet across. The stems are hollow and 2-4 inches in diameter.
This plant is also a public health hazard. Giant hogweed exudes a clear sap which sensitizes the skin to ultraviolet radiation. Humans often develop severe burns to the affected areas resulting in blistering and painful dermatitis. Blisters can later develop into purplish or blackened scars. This area of the skin can remain sensitive to sunlight for over 10 years.