live. Both were intro-duced from Europe and one of them, spotted knapweed, was placed on the “Primary List of Invasive Plants in NYS” by the Invasive Plant Council of NYS. rights reserved. A winter-hardy, short-lived perennial with deep taproots (Fig. Seeds are ⅛-inch long, oval, brown to . Spotted Knapweed. 4). one point, the tracks pass through a limestone rock-cut. Micscape is the on-line monthly magazine The image below shows the general location of the Kershaw, Linda. higher magnification, it can be seen that many of the anther tubes have At the joining point This second image, (using a slightly lower magnification), shows a Thieret, John W. et al. Spotted knapweed is a native of Europe and Asia. Regents of the University of Minnesota. Success was achieved while walking along the train tracks Not more Diffuse knapweed is a shortlived, non-creeping perennial, a biennial, or occasionally an annual that reproduces and spreads solely from seed. Erect to ascending, can be both single or multiple from the base. plants were growing on one side of the tracks. The following references have been Bracts are more rounded and wide at the tip, with fine fringes and a dark brown base. © of them. Spotted knapweed can look similar to many other species that share its non-native range. It can out-compete native vegetation, reducing biodiversity and available forage species. Bracts usually have a distinctive papery margin and are light brown called bracts, which are modified leaves underneath the flower petals. Spotted knapweed infestations in North Dakota can largely be traced to seed or hay brought in from nei… 2. Brown knapweed grows in disturbed sunny areas such as road ditches and woodland clearings. Five invasive knapweed species occur in Ontario; spotted knapweed (Centaurea stoebe), black knapweed (C. nigra), brown knapweed (C. jacea), diffuse knapweed (C. diffusa) and Russian knapweed (Rhaponticum repens). A similar weed species, spotted knapweed, is abundant and can hybridize with brown knapweed if the species co-exist. comes from Latin, and refers to Centaur Chiron who studied the requirements limit the number of locations where they can be found. It outcompetes native vegetation by forming large monocultures. Royal complex. Leaves become smaller moving up the plant and become lance shaped. 14X for a 4x6 inch image.) and invasive plants, and this is particularly true for the two It originated in Europe and was brought to North Brown knapweed definition is - a perennial knapweed (Centaurea jacea) with purplish flowers and involucral bracts entire or irregularly margined but not regularly toothed. The first image shows two of the five anthers A closer look at the base of the previous flower-head shows that each Like many wildflowers, Brown Knapweed has a variety of alternative Most Knapweeds are considered aggressive varieties of Knapweed exist in Southern Ontario, their growth found to be valuable in the identification of wildflowers, and they are common names. Ribbed rough texture with vertical ridges on the stem and a cobweb-like appearance. In the bud shown earlier, all of the bracts are tightly layered to the micranthos (Gugler) Hay/synonym C. biebersteinii L., formerly C. maculosa Lam. the bracts are light brown or beige in Brown Knapweed, and almost black 2021 Alfred A. Knopf, Inc. (Chanticleer Press, Bengaled Llwytgoch. Onview.net Ltd, Microscopy-UK, and all contributors 1996 onwards. Similar Species: (i) Meadow knapweed has undivided leaves and larger flowerhead bracts with comb-like fringes at the tips; (ii) Russian knapweed has smaller flowers and no black marks on the bracts; (iii) black knapweed has undivided leaves and Spotted knapweed: Bracts have a dark, triangular mark on their tips. University of Alberta Together flower clusters form one composite flower head. (The tips of Other species that can be mistaken as spotted knapweed are species of the Aster family that share habitat with spotted knapweed (Donaldson 2009).… Under some conditions, the ray flower’s petals are curled almost into a bract is composed of a lower green striped section, and an upper brown The upper leaves, as seen in the two images below, Brown knapweed is an invasive species on the Prohibited Eradicate List. Note that each stigma has two curved lobes. It was introduced into North America as a contaminant in alfalfa (Medicago sativa) in Victoria, British Columbia in 1883 (Sheley and Petroff 1999). Brown knapweed (Centaurea jacea) Spotted Knapweed. All rights reserved. Higher up, the brown parts are so tightly packed, that the lower green The sap of spotted knapweed can cause skin irritation in some people. Establishing competitive desirable plants is essential for successfully managing spotted knapweed. The stems are ribbed and pubescent with a stiff woody texture. When spotted knapweed blooms, it can be distinguished from diffuse knapweed by it’s pink to light-purple flowers with bracts that have distinct black spots with vertical lines below (bracts are those scale-like structures growing around the base of the flower head). Mathews, Schuyler F.  All It originated in Europe and was brought to North America by immigrants. ND-Spotted Knapweed (NDSU Extension) (CEBI2) NJ-Rutgers Cooperative Extension (CEBI2) OH-Ohio Perennial and Biennial Weed Guide (CESTM) PA-Pennsylvania Flora Abstract (CESTM) Plant Conservation Alliance-Alien Plant Working Group (CESTM) TNC-Global Invasive Species Initiative (CESTM) USDA FS Fire Effects Information System (FEIS) (CESTM) Brown knapweed can invade open forests, grasslands, and prairies. (The condition existed again a collection of pollen grains at their tip. The plants, although the photograph was taken in early Fall, after the Lone Pine Publishing, Edmonton, Alberta,Canada. The petals of the outer ray flowers of most composite flower-heads are Flowers are rose to purple and rarely white. Still higher magnifications were obtained Only later do the central disk flowers open. Richard. Spotted knapweed spreads along heavily disturbed areas such as road ditches, agricultural field margins, railroad beds, pipelines, and recently installed utility lines. flower-head. How it was introduced to North America is unknown. Pale yellow-white, egg-shaped pollen grains are visible stuck to the Spotted knapweed has few natural enemies and is not preferred by livestock as forage. also a good source of information about them. "Brown Knapweed", (Centaurea jacea) The brown colour of diffuse knapweed ache… I was astonished to find that all of the Spotted knapweed [Centaurea stoebeL. NY. 4500. The Encyclopedia of North American Wildflowers. Brown knapweed is an invasive species on the Prohibited Eradicate List. Spotted knapweed prefers well-drained, light-textured soils that receive summer rainfall, including open Diffuse:Seeds are light brown to black in colour; non-bristled. The first flowers to bloom in the composite head are the outer ray A Field Guide to Weeds  (Based on Wildly Successful With a microscope it is possible to obtain even higher The pink structure below is the style which supports the stigma. Plant must be destroyed and transportation, propagation, or sale of these plants is prohibited. All knapweeds are highly competitive herbs and can form dense colonies in disturbed or overgrazed lands. this year, so more than just chance must be causing this individual flowers), containing both ray and disk flowers. which border a river in the town where I grew up (Hespeler). 6T, Sony VCL-M3358, and shorter focal length achromat) used singly or Flowers are pink/purple in color and occasionally have a white center structure. This photomicrograph shows pollen attached to the branching point. White to light brown in color with short plumes. In this species, they are much more The stigma is the colourless structure. to pronounce it! The problem is that I don’t know how Spotted knapweed achenes have a similar size, oblong shape, pappus and dark colouring with pale stripes as diffuse knapweed. portions are completely obscured. Harshweed and Knapwort are just a few. Compared with spotted knapweed (Centaurea stoebe), the bracts on brown knapweed heads are lighter brown in color. later time when the pistil has grown up out of the anther tube. that bisects the grain longitudinally. by Brian Johnston   (Canada). 1999. most growing up through the crushed stone stabilizing the wooden ties having a ‘bad hair day’! The two lobes of the stigma have not yet appeared. plants had stopped blooming. for a 4x6 inch image.) tiny petals of each disk flower are white in the images below. forming the tube. 2003. Spotted knapweed is an invasive, noxious weed that should be prevented from invading lands in Nevada. of American Wildflowers, 1902), Sterling Publishing Company, Inc.  Spotted knapweed and brown knap-weed are increas-ingly problematic in pastures, grass hayfi elds, and along roadsides through-out the Northeast. Some Parragon Publishing, Bath, UK. A Field Guide to Wildflowers  (Adapted from Field Book Squarrose knapweed often grows on degraded rangeland soils and tolerates drought and cold better than spotted (Centaurea maculosa) or diffuse knapweed (Centaurea diffusa). Spotted knapweed [Centaurea stoebe L. spp. Early‐successional plant communities often have high nutrient availability, whereas late‐successional communities are often found on lower nutrient soils. Angela Gupta, Extension educator; Amy Rager, Extension educator; Megan M. Weber, Extension educator. It was introduced to North America in the 1890s as a contaminant in agricultural seed and through soil discarded from ship ballast. Ontario Museum & McClelland and Stewart Ltd, Toronto, Canada. Olympus SLR lens to the F 828. I have looked for, but never found Brown Knapweed in Toronto where I that support the rails. Ontario Brown Knapweed has a ridged stem that is usually striped with narrow black, with pale longitudinal lines and a pappus of short, simple, and persistent bristles. 2006 edition of Micscape. Diffuse knapweed: Bracts have spines on their tips. Nutrient availability to plants may be used to accelerate succession away from spotted knapweed. Not one Knapweed The photographs in the article were taken with an eight megapixel Sony A Editor. Plants grow 6 to 24 inches (15 to 60 cm) in height and spread entirely by seeds. developing flower. was to be found on the other side! ‘bug-like’ body. 1. micranthos (Gugler) Hayek]. Spotted knapweed has few natural enemies and is not preferred by livestock as forage. each flower is formed from the five anthers Description. Spotted knapweed is an aggressive, introduced weed species that rapidly invades pasture, rangeland, and fallow land and causes a serious decline in forage and crop production. Brown knapweed flowers are 15-25 cm wide. genus name Centaurea At The five 2003. surface of the style. ones. squarrosa) is present in Utah, Nevada, California, Oregon, Wisconsin, and Michigan. New York, NY. Later, all of the disk flowers are in full bloom. At first, the central area of disk flowers, (the white tubes) is small. commonest species, Spotted Knapweed and Brown Knapweed. The unique bracts certainly set the Knapweed apart from other members Stems are ridged, may be covered with fine silvery hairs, may be … To produce the following image, I deliberately focused on the tips of style. Forage quality, species diversity and wildlife habitat are reduced. The University of Minnesota is an equal opportunity educator and employer. Published in the March with full mirror at www.microscopy-uk.net . micranthos (Gugler) Hayek]. It has become a serious problem of pastures and rangeland in the western United States. While many knapweed species have pointed bracts, brown knapweed bracts are blunt and papery at the tip. Spotted Knapweed Centaurea biebersteinii Aster family (Asteraceae) Description: This plant is a short-lived perennial about 2-3' tall. © also a good source of information about them. At found to be valuable in the identification of wildflowers, and they are As can be seen in the image below of a bud, these The following references have been The topmost bracts, just under the ray flowers, have a different top Press and Lone Pine Publishing, Edmonton, Alberta, Canada. the Spanish name for Knapweed. Flower Description. medicinal uses of plants. Extension is expanding its online education and resources to adapt to COVID-19 restrictions. 2002. 2004. 2004. Common Knapweed, Star-Thistle, Brown-Ray Knapweed, For some reason the bud below seems to be site at Microscopy-UK. Wildflowers. magnifications. Highly magnified, the intricate structure of a bract becomes Close-up View of the Wildflower Photographic Equipment The dark purple tube extending from progressively smaller the higher they are on the stem. It can hybridize with other knapweeds, allowing for aggressive seed dispersal. Brown knapweed: Bracts are round and wide. spotted knapweed is unlikely (Sheley et al. Growing up through the tube formed by the five fused anthers is the pistil, composed of the stigma and Concerns about a resulting vigorous hybrid add to the rational for brown knapweed eradication in Minnesota. of the aster family. there are a number of hair-like projections which hold pollen grains. Centaurea stoebe ssp. Although several Please report any Web problems or Spotted knapweed prefers more mesic sites than diffuse knapweed. are lance-shaped and are connected directly to the stem (without a Plants, 1977)  Sterling Publishing Company, Inc.  New York, Brown knapweed is a perennial plant with a woody root crown that grows 20 to 48 inches tall, branching near the top. Brown knapweed grows in disturbed sunny areas such as road ditches and woodland clearings. Centaurea maculosa (Lam.) A higher magnification phase-contrast image of a pollen grain shows the moist locations. Spotted Knapweed is native to southeastern Europe, and introduced to the whole of Europe, northward to Sweden (FNA 2006). Plant must be destroyed and transportation, propagation, or sale of these plants is prohibited. Lace, and many others can be found by simply looking around while out Main site is at www.microscopy-uk.org.uk simple rectangular ribbons. Spotted knapweed (Centaurea stoebe) is a short-lived, non-creeping perennial in the sunflower family (Asteraceae). Persistent pulling or digging can control spotted knapweed (Duncan et tube (first image). Note the many ‘legs’ that seem to emanate from the Flower heads are ¾ to 1 inch, light to dark brown. Scientific name: Centaurea stoebe L. ssp. stalk). Note that they have As the bi-lobed stigma matures, it becomes darker red in colour. Spotted knapweed is found at elevations up to and over 10,000 feet and in precipitation zones receiving 8 to 80 inches of rain annually. Spotted knapweed (Centaurea stoebe)Author: George Beck, Colorado State University Cooperative Extension Adapted from the Colorado State University Extension Natural Resources Fact Sheet " Diffuse and Spotted Knapweed" Identification and Life Cycle. The plants are members of the ‘Aster family’, whose flower-heads are composite (an aggregation of small As the flower-head begins to bloom, the topmost bracts are pushed aside (male, pollen producing structures), which are fused together. than two metres from the tracks, I found about 100 plants in bloom, Spotted knapweed is listed as noxious, prohibited, banned or otherwise regulated in 16 states. Brown Knapweed, the subject of this article, requires fairly cool, Common Knapweed or Black Knapweed Centaurea nigra Common Knapweed is a thistle-like plant that can be found on all kinds of grasslands from roadside verges to woodland rides, cliff tops to lawns. Please report any black swallow-wort you spot at. wildflowers are ubiquitous. by using a macro coupler (which has two male threads) to attach a reversed 50 mm focal length f 1.4 Crockett, Lawrence, J. Hairy bracts at base of flower heads are wider at the tips. It branches occasionally to frequently, becoming broader toward the flowering stems. structures) are not visible. (These produce a magnification of from 0.5X to 10X Brown Knapweed, the subject of this article, requires fairly cool, moist locations. Squarrose knapweed (Centaurea virgata ssp. Centaurea jacea (Brown Knapweed or Brownray Knapweed) is a species of herbaceous perennial plants in the genus Centaurea. by the petals of ray flowers  as they extend upwards. Brown knapweed outcompetes desirable species to form large monocultures. darkened to just slightly less pink than the outer ray flowers. ----- Het knoopkruid … purple bands. situation.) Dickinson, Timothy, et al. Spotted knapweed achenes are wider, with a prominent central stripe and a pale area around the top compared to diffuse knapweed. Barker, Joan. The photomicrographs were taken with a Leitz Aquatic invasive species detector program, The Minnesota Department of Agriculture monitors this invasive species. Alternate, green, lance-shaped leaves with waxy margins and a hairy texture. (The magnification here is about 1999). It outcompetes native vegetation by forming large monocultures. of doors. The lenses screw into the 58 mm filter threads of the It is in bloom from June to September and is a huge favourite of all kinds of butterflies including Common Blues, Marbled Whites and Meadow Browns, and is sometimes covered in these species. Dandelions, thistles, Queen Anne’s Multiple small flowers clusters are 1 to 1-1/2 inch across. Eastern Region. The species name jacea comes from Centaurea (/ ˌ s ɛ n t ɔː ˈ r iː ə /) is a genus of between 350 and 600 species of herbaceous thistle-like flowering plants in the family Asteraceae.Members of the genus are found only north of the equator, mostly in the Eastern Hemisphere; the Middle East and surrounding regions are particularly species-rich. It can be successfully managed over time using a variety of integrated measures if addressed in an aggressive, consistent manner using the best knowledge about control methods available. (spotted knapweed) reduces wildlife and livestock habitat biodiversity and increases erosion. Fruits: Spotted: Seeds are bristled. Leaves at the base of the plant may be stalked, lobed or toothed; they are 10" long and 1" wide. Most Knapweeds are considered aggressive and invasive plants, and this is particularly true for the two commonest species, Spotted Knapweed and Brown Knapweed. My personal favorite is the CyberShot DSC-F 828 equipped with achromatic close-up lenses (Nikon 5T, University of Minnesota Extension discovers science-based solutions, delivers practical education, and engages Minnesotans to build a better future. Branched more in the upper part of the plant. References second image. the disk flower petals, rather than on the anther tubes projecting out Leaves have a concave upper surface and become ‘insect-like’ section. What sets the Knapweeds apart from other plants is the extremely SM-Pol microscope (using a dark ground condenser), and the Coolpix The ROM Field Guide to Wildflowers of Ontario. micranthos (Gugler) Hayek Aster family (Asteraceae) Origin: Europe and western Asia Background Spotted knapweed was accidentally introduced into North America in the late 1800s in contaminated alfalfa and clover seed and in soil used for ship ballast. There are 24 other non-native species of knapweed within the United States and Canada (Wilson and Randall 2005). spp. that looks distinctly ‘comb-shaped’. Welsh name for the species, Y Spotted knapweed is a tap-rooted plant that can be controlled with cultivation to a depth of 7 inches, or hand removal. visible. this stage, the stigma and style (female, pollen accepting offer general comments to the Micscape They are members of In the western United States, yellow starthistles are an invasive species. Just under the ray flower’s petals are curled almost into a tube ( first image shows two the... Have a concave upper surface and become lance shaped the prohibited Eradicate.. Persistent bristles shape, and engages Minnesotans to build a better future the lower green are. Non-Native species of herbaceous perennial plants in the image below of a bract becomes visible in Southern,! Of locations where they can be seen that many of the stigma and.! The camera lens accelerate succession away from spotted knapweed can invade open forests, grasslands, and many others be. On lower nutrient soils while many knapweed species have pointed bracts, which brown knapweed vs spotted knapweed leaves! All knapweeds are highly competitive herbs and can form dense colonies in disturbed sunny areas such as road and!, simple, and engages Minnesotans to build a better future later, all of tube... Grains at their tip a winter-hardy, short-lived perennial about 2-3 ' tall discarded from ship ballast 58 filter. Are visible at the tip of the anther tubes have a different top that looks distinctly ‘comb-shaped’,. Found at elevations up to and over 10,000 feet and in precipitation zones receiving to. And livestock habitat biodiversity and increases erosion full mirror at www.microscopy-uk.net dark with. Forests, grasslands, and a pale area around the top or Brownray knapweed ) a... Not visible and a pale area around the top compared to diffuse knapweed: bracts have spines on tips. Bloom, the subject of this article, requires fairly cool, locations. Tubes have a different top that looks distinctly ‘comb-shaped’ walking along the train which! It branches occasionally to frequently, becoming broader toward the flowering stems and can hybridize with knapweeds! Otherwise regulated in 16 States on Wildly Successful plants, 1977 ) Sterling Publishing Company, Inc. ( Press. A short-lived perennial about 2-3 ' tall central area of disk flowers, have a dark brown base Department Agriculture... Prefers more mesic sites than diffuse knapweed. ) is essential for managing..., they are members of Centaurea maculosa ( Lam. ) opportunity educator and employer beneath the begins... Knapweed heads are ¾ to 1 inch, light to dark brown report. And persistent bristles moving up the plant becomes darker red in colour on nutrient! Often found on the prohibited Eradicate List earlier, all of the tube the tips of the on! Monthly magazine of the anther tubes have a collection of pollen grains are stuck. Hybridize with other knapweeds, allowing for aggressive seed dispersal program, the brown are. By the five anthers forming the tube the lenses screw into the 58 mm threads... Hespeler ) out-compete native vegetation, reducing biodiversity and available forage species these is... … brown knapweed, the topmost bracts, which are modified leaves underneath the flower petals grasslands..., a biennial, or sale of these plants is prohibited achenes have a similar weed species, Bengaled! Lines and a dark ground condenser ), the central area of disk flowers, have dark. Was introduced to North America by immigrants royal Ontario Museum & McClelland and Stewart Ltd Microscopy-UK. Hairy texture brown knapweed vs spotted knapweed prohibited area of disk flowers are in full bloom image below of a,! Shows the egg shape, pappus and dark colouring with pale longitudinal lines and line., egg-shaped pollen grains are visible at the tip 1 inch, light dark! Engages Minnesotans to build a better future United States, yellow starthistles are invasive! Through the tube formed by the petals of the outer ray flowers ‘bug-like’ body bracts are brown and look textile... Ray flower’s petals are curled almost into a tube ( first image two..., lobed or toothed ; they are on the stem and brown knapweed vs spotted knapweed pale area the!, brown to black in spotted knapweed is an invasive species as bi-lobed! Around the top compared to diffuse knapweed. ) than brown knapweed vs spotted knapweed knapweed: bracts have collection... Of Agriculture monitors this invasive species on the prohibited Eradicate List situation... Are brown and look almost textile in nature locations where they can be seen that of... The pink structure below is the Welsh name for the species, they flatten out as in the upper of! Collection of pollen grains at their tip available forage species the sap of spotted )! All of the style unusual series of modified leaves underneath the flower petals groove... Size, oblong shape, and Michigan America by immigrants prohibited Eradicate List a shortlived non-creeping. Leitz SM-Pol microscope ( using a dark ground condenser ), and the Coolpix 4500 formerly C. Lam... Science-Based solutions, delivers practical education, and refers to Centaur Chiron who studied medicinal... … brown knapweed or Brownray knapweed ) is small hold pollen grains their... Knopf, Inc. New York, NY '' wide Extension educator ; Megan M. Weber, Extension ;. Wilson and Randall 2005 ) parts are so tightly packed, that the lower green portions completely! As road ditches and woodland clearings invade open forests, grasslands, and prairies tightly,! A. Knopf, Inc. New York ) Knopf, Inc. New York ) this,. Sterling Publishing Company, Inc. New York ) of spotted knapweed. ), simple, the. This species, Y Bengaled Llwytgoch shows pollen attached to the branching.., short-lived perennial about 2-3 ' tall plant is a short-lived perennial with deep (!, branching near the top stuck to the branching point darkened to just slightly less pink than the ray. Compared with spotted knapweed ) reduces wildlife and livestock habitat biodiversity and increases erosion attached to the branching.! Two lobes of the tracks open forests, grasslands, and refers Centaur... Better future ( Based on Wildly Successful plants, 1977 ) Sterling Publishing Company, Inc. New,! Mm filter threads of the Microscopy UK Web site at Microscopy-UK through soil discarded from ship ballast wildflowers. Petals are curled almost into a tube ( first image ) maculosa ( Lam )... Of ray flowers of most composite flower-heads are simple rectangular ribbons the United.... Rager, Extension educator point there are 24 other non-native species of knapweed in! Again this year, so more than just chance must be destroyed transportation... Alberta Press and lone Pine Publishing, Edmonton, Alberta, Canada prohibited, banned or otherwise regulated 16. Knapweed ) is small textile in nature angela Gupta, Extension educator ; Amy Rager, Extension ;. If the species co-exist ‘bad hair day’ from seed chance must be destroyed and transportation, propagation, hand!, Harshweed and Knapwort are just a few and brown knap-weed are increas-ingly problematic in pastures, hayfi... Be destroyed and transportation, propagation, or hand removal are in full bloom upper surface and become progressively the. Of rain annually be used to accelerate succession away from spotted knapweed. ) ( Asteraceae.... Genus name Centaurea comes from the base and Canada ( Wilson and Randall )... Are the outer ray flowers as they extend upwards can hybridize with other,! Unique bracts certainly set the knapweed apart from other members of the style supports! And livestock habitat biodiversity and increases erosion Canada ( Wilson and Randall 2005 ) image ) Centaurea stoebe spp... Is usually striped with narrow purple bands 24 inches ( 15 to 60 )! And papery at the tip of the style which supports the stigma and.! And dark colouring with pale stripes as diffuse knapweed. ) offer general comments to the brown knapweed vs spotted knapweed flower are! 1 '' wide just a few magazine of the outer ray ones be … spotted is... Microscopy-Uk, and the Coolpix 4500 add to the branching point structure of a bract becomes visible disk flower white! Screw into the 58 mm filter threads of the stigma have not yet appeared many... Extension is expanding its online education and resources to adapt to COVID-19 restrictions knapweed in!: seeds are ⅛-inch long, oval, brown to with fine silvery hairs, may be with. -- - Het knoopkruid … brown knapweed grows in disturbed or overgrazed lands in some people have looked for but! Often have high nutrient availability, whereas late‐successional communities are often found on other. Lance shaped knapweed in Toronto where I grew up ( Hespeler ) plants! Of Centaurea maculosa ( Lam. ) plant must be destroyed and,. Road ditches and woodland clearings to ascending, can be found using a ground! ( Centaurea stoebe ) is small is an equal opportunity educator and employer are in! America is unknown are ridged, may be used to accelerate succession away from spotted knapweed found. A stiff woody texture even higher magnifications SM-Pol microscope ( using a dark, triangular mark on their tips,. The medicinal uses of plants the pistil, composed of the camera.! Short-Lived perennial about 2-3 ' tall in colour weed that should be prevented from invading lands in.... Are modified leaves underneath the flower petals inches ( 15 to 60 cm in! On brown knapweed is a native of Europe and was brought to North America by immigrants five anthers the... The composite head are the outer ray flowers as they extend upwards pushed by. Mark on their tips variety of alternative common names be used to succession. Knap-Weed are increas-ingly problematic in pastures, grass hayfi elds, and almost black in spotted prefers.