navigation
Previous Plant Next Plant

xxxHome
x
xAbsinth wormwood
x
xAlligatorweed
x
xAmerican Lotus
x
xAmerican Pondweed
x
xAmpelopsis
x
xAustralian Pine
x
xBaccharis
x
xBamboo
x
xBanana Passionflower
x
xBarnyard Grass
x
xBermuda Grass
x
xBirdsfoot Deervetch
x
xBlack Locust
x
xBlack Mustard
x
xBlue Lettuce
x
xBrazilian Elodea
x
xBrazilian Peppertree
x
xBufflegrass
x
xBull Thistle
x
xBulrush
x
xBurdock
x
xButtonbush
x
xCanada Thistle
x
xCattails
x
xCheatgrass
x
xCherry Silverberry
x
xChinaberry
x
xChineese Lespedeza
x
xChinese Bush Clover
x
xChinese Privete
x
xChinese Tallow Tree
x
xClimbing Hempweed
x
xCogon Grass
x
xCommon Buckthorn
x
xCommon Cocklebur
x
xCommon Reed
x
xCommon Sowthistle
x
xCoontail
x
xCottonwood
x
xCrownvetch
x
xCurlyleaf Pondweed
x
xDalmation Toadflax
x
xDiffuse Knapweed
x
xDuckweed
x
xDyer's Woad
x
xElephant Ears
x
xElodea
x
xEnglish Ivy
x
xEurasian Watermilfoil
x
xEuropean Stickseed
x
xField Bindweed
x
xField Mustard
x
xField Sowthistle
x
xFloating Heart
x
xFloating Primrose
x
xFlowering Rush
x
xFragrant Water-Lilly
x
xGallant Solder
x
xGarlic Mustard
x
xxGiant Foxtail
x
xGiant Reed
x
xGiant Salvinia
x
xGlossy Buckthorn
x
xGorse
x
xHalogeton
x
xHempnettle
x
xHimalayan Raspberry
x
xHoary Cress
x
xHorsenettle
x
xHorseweed
x
xHoundstongue
x
xHydrilla
x
xIvy Gourd
x
xJapanese Barberry
x
xJapanese knotweed
x
xJohnson Grass
x
xJointed Goatgrass
x
xKlamath Weed
x
xxKochia
x
xKoster's Curse
x
xKudzu
x
xLeafy Spurge
x
xLimnophila
x
xLongspine Sandbur
x
xMalaleuca
x
xMedusahead
x
xMiconia
x
xMimosa
x
xMiramar Weed
x
xMultiflora Rose
x
xMusk Thistle
x
xNepalese Brown Top
x
xNorway Maple
x
xOld World Climbing Fern
x
xOrange Hawkweed
x
xOxeye Daisy
x
xPale Yellow Iris
x
xPaper Mulberry
x
xPara Grass
x
xParrotfeather
x
xPerenial Pepperweed
x
xPeriwinkle
x
xPlumeless Thistle
x
xPoison Hemlock
x
xPorcelainberry
x
xPrincess Tree
x
xPuncturevine
x
xPurple Loosestrife
x
xPurple Starthistle
x
xPupletop Vervain
x
xQuackgrass
x
xQueen Anne's Lace
x
xRedroot Pigweed
x
xReed Canarygrass
x
xRice Cut-Grass
x
xRiviere Golden Bamboo
x
xRussian knapweed
x
xRussian Thistle
x
xSalvinia minima
x
xScotch Broom
x
xScotch Thistle
x
xSkeleton Weed
x
xSlender Naiad
x
xSmartwed
x
xSmooth Brome
x
xSouthern Naiad
x
xSpatter-Dock
x
xSpiny Naiad
x
xSpotted Knapweed
x
xStrawberry Guava
x
xSulfur cinquefoil
x
xSunflower
x
xSwallowworts
x
xTamarisk/Salt Cedar
x
xTansy Ragwort
x
xTeasel
x
xTexas Blueweed
x
xTorpedo Grass
x
xTree of Heaven
x
xTropical Soda Apple
x
xTumble Pigweed
x
xUruguayan Primrose
x
xVariable-Leaf Milfoil
x
xWater Buttercup
x
xWater Chestnut
x
xWater Moss
x
xWater Paspalum
x
xWater Shield
x
xWater Hyacinth
x
xWater Lettuce
x
xWater Willow
x
xWestern Water Hemlock
x
xWhite Sweetclover
x
xWhitetop
x
xWild Mustard
x
xWild Parsnip
x
xWillows
x
xYellow Nutsedge
x
xYellow Starthistle
x
xYellow Toadflax


Diffuse Knapweed - Centaurea diffusa
Family: Asteraceae

Description

Diffuse knapweed is a non-creeping, erect annual, biennial or sometimes shortlived perenial that reproduces and spreads exclusively from seed.

This species of knapweed can be mistaken for spotted knapweed, a slightly more common species that inhabits the same range.

Interesting facts (Inroduction)

Diffuse knapweed is an introduced plant from southern Europe to north-central Ukraine. It is a competitive plant in dry, light, porous soils in Europe and thus likes similar habitats in the United States. It is believed to have been introduced as a contaminant of alfalfa from Turkestan near the Caspian Sea. The first indication that it was in the US was from Washington in 1907.

Biocontrol

Several biological control agents, including a root boring beetle and moth, 2 seed head gall flies, and a seed head weevil are available but are not proven effective

Links to more information

Species info - From Colorado State University

Species Info - Idaho Invasive plant page

Information - complete information from the noxious weed board in washington state.


Website, video, and graphics by Rob Nelson
For more information on this plant or management please contact US Army Corp of Engineers

 

New Biology Video Podcast The Wild Classroom Biology Concepts Biodiversity Home