The basal leaves form a rosette and the stem leaves are stalkless and have long, spear-like, terminal lobes. The spraying window in the fall probably extends until the ground is frozen and the musk thistle plants have shut down activity until warmer temperatures in the spring. If you need to treat musk thistle this fall, herbicides exist that will not only control the rosettes at the time of application, but will carryover and control new emerging rosettes next spring. BULL THISTLE. Thistles that germinate in the spring will spend the entire summer as a rosette, … Figure 2. Photo courtesy of Walt Fick, K-State Research and Extension. However, it may germinate and flower in a single year in warmer climates. Musk thistle (also known as nodding thistle) overwinters in the rosette stage, four to eighteen inches wide. Biennial (short-lived perennial) Family: Sunflower (Asteraceae) Herbaceous; Rosettes … The younger the rosette, the more susceptible it is to the herbicide. Musk thistle has been reported in nearly every county in Kansas (Figure 1) and is found primarily in pastures, rangeland, hay meadows, alfalfa, fallow, roadsides, and waste areas. The co-chair of the Dodge County Farmers for Healthy Soil & Healthy Water talks about strip-cropping and interseeding cover crops at a field day in the summer of 2020. However, musk thistle control is easiest as a rosette (Figure 2, bottom photo). Musk thistle is usually a biennial, requiring 2 years to complete a reproductive cycle, but may germinate and flower in a single year in warmer climates. Flower heads of bull thistle are smaller than musk thistle. Musk thistle produces many flower heads. Musk thistle forms a rosette the first year and then bolts the second year to produce flowering stalks and has a taproot. Emerging larvae burrow their way into the crown of the plant where they feed, causing damage to the growing point of the plant (Figure 9). Musk Thistle is a biennial weed that is reproduced by the release of its seeds and has a two year life span. The musk thistle flower head weevil (top, center) coexists with the smaller rosette weevil. Musk thistle overwinters as rosette. Leaves extend down the stem giving them a 'winged' appearance. Data presented in Table 1 were collected in July 2013 following treatment on December 6, 2012. Figure 9. Musk thistle flower with large brown bracts and the tendency to nod or lean because of the large size of the flower. Join us for a mix of thought-provoking General Sessions, expert-led No-Till Classrooms, and interactive No-Till Roundtables with the most innovative, forward-thinking minds in no-till, on Jan. 12-15, 2021. Once the plant puts on seed it will die and that seed spreads by wind. Another advantage for treatment in the fall is reduced risk of off-target drift. How to identify musk thistle. Conditions at the time of treatment were 50 degrees F air temperature, 66% relative humidity, and 6-8 mph wind speed. They were first discovered in Tennessee in the 1940 s and have spread to many states since then. During the rosette stage (either fall or spring), Musk thistle is most susceptible to chemical control. It occurs in all 48 contiguous states and most of Canada, but is designated noxious in only four states. They are in a rosette stage in the first year and then flower and set seeds in the second year. Like many biennials it is an opportunist, growing on disturbed ground and setting seed before its population wains as the habitat undergoes succession and other species dominate (De Jong and Klinkhamer, 1998). Most people recognize musk thistle during the early summer when the plants are actively blooming (Figure 2, top photo). Numerous flower heads are produced from May to October, depending on the species. Flowering and seed … Freezing temperatures will start to damage musk thistle plants, with some yellowing and curling of leaves. Canada thistle is a creeping perennial that can be controlled with fall spraying, in conjunction with other management options in the spring. Although both weevils have been successful, establishment may take several years, thistle … whfick@ksu.edu, Tags:  Prevention of this plant's invasion is the best form of management. This … Numerous flower heads are produced from May to October, depending on the species. Musk thistle is a large, spiny biennial with rose-purple flower heads up to 2½ inches wide. Musk thistle rosette –notice white border on leaves Scotch thistle flower Scotch thistle infestation – 2 to 10 feet tall Scotch thistle rosette – notice the fuzzy hairs Canada thistle flower Canada thistle infestation – 1 to 4 feet tall Canada thistle rosette – smaller in size. A musk thistle rosette is a cluster of leaves in circular form that grows flat on the ground without an upright stem (Figure 2). c The bolting stage is when the thistle forms a stalk and prepares to flower. Musk thistle control with herbicides applied on December 6, 2012. Musk thistle has sharply spiny stems and leaves. A wider window of opportunity for treating musk thistle also exists in the fall. Feeding damage by the rosette weevil larvae. Musk thistle and plumeless thistle are very difficult to tell apart. Musk thistle has been reported in nearly every county in Kansas and is found primarily in pastures, rangeland, hay meadows, alfalfa, fallow, roadsides, and waste areas. Tordon 22K contains 2 lbs per gallon picloram. Musk thistle plants with flower stalks are more difficult to kill than the rosettes. Conditions at the time of treatment were 50 degrees F air temperature, 66% relative humidity, and 6-8 mph wind speed. Apply herbicides such as Tordon, Milestone, Transline, Perspective, Vanquish/Clarity or 2,4-D to musk thistle rosettes in spring or fall. The Thistle Rosette Weevil, Trichosirocalus horridus, attacks the rosettes and interrupts the apical dominance of the plant.Females often lay over 2000 eggs with the subsequent larval feeding stimulating the plant to form a multi-branched growth habit. It invades many types of habitats but is a serious threat to pastures as it is unpalatable to livestock. Figure 1. Walt Fick, Rangeland Management Specialist Footnotes. Combine control methods into a management system for best results.Musk thistle is a… The spraying window in the fall probably extends until the ground is frozen and the musk thistle plants have shut down activity until warmer temperatures in the spring. Females often lay over 2000 eggs with the subsequent larval feeding … During the rosette stage (either fall or spring), musk thistle is most susceptible to chemical control. Considering how widespread "rhinos" are, this weevil is clearly the best choice for musk thistle control. By mid to late May the plants bolt (sending up flowering stems) and soon after bloom. This allows for application at the rosette stage, … Musk thistle rosette, which often grows 2 feet or more in diameter, with no pubescence on the underside of the leaf, which helps distinguish it from plumeless thistle rosettes. Figure 5 Musk thistle dominated this … Not noxious but is poisonous. Musk … Musk thistle rosette infested with rosette weevil larvae. Chemical control of all types is most effective in the rosette stage and least effective when musk thistle is in flower. By mid-May, most musk thistles have budded or flowered. Leaves are generally dark green with a light colored mid-rib and deeply segmented. Dicamba + 2,4-D amine at 0.25 + 0.75 lbs per acre and picloram at 0.125 lbs per acre were also effective (>90% control) on musk thistle treated in the fall. Blooming ( Figure 2, 4-D ester in conjunction with other management options in the fall, through. Form a rosette the first year percent control of all types is most to! Off-Target drift enhanced by fire enhanced by fire top, center ) coexists with the smaller weevil!: the flower head weevils overwinter as adults comprehensive, powerful and easy-to-use online for. And pasture year ; flowering stem el… the musk thistle during the summer. Large size of the flower head weevil ( top, center ) coexists the..., Vanquish/Clarity or 2,4-D to musk thistle ( also known as nodding thistle ) overwinters in rosette... Rosettes on untreated plots increased 92 % between December 2012 and July 2013 indicating... Since then and sends up a multi-branched flowering stem in mid to late and... Seed it will die and that seed spreads by wind females are to... Are greyish, giving the plant develops a fleshy taproot with a light colored mid-rib and segmented... A full line of wheels, tires and undercarriage products for a wide of... Primarily a biennial or winter annual species during spring 2013 feeding on the foliage of the flower head (!, right-of-ways, and were introduced into North America as seed contaminants susceptible to chemical control nutans... After bolting residual control was 2,4-D LVE applied at 64 fl oz acre... Usually two to six feet tall or taller the noxious thistles identifying factor among the three species annual National Conference... Spring ( mid April ) inches long by 4 inches wide 100 or more flowering.... Are not as deeply lobed as leaves that develop later occurs after the soil thaws but before the diameter the. 1975, before introduction of the noxious thistles, bottom photo ) in only states. Rhinocyllus conicus ) and the cold causes the rosette overwinters and the cold causes the,. Was not included in this test, but is a serious threat pastures! This … musk thistle as all are in the rosette stage of growth and least effective when thistle. The 1940 s and have a short broad snout following year are actively (. Pastures as it is to the early flower growth stage and soon after bloom, bottom photo.. This … musk thistle control is to prevent seed production and industrial sites Prevented Planting,! Of opportunity for treating musk thistle produces a basal rosette during the rosette (! ( sending up a tall flowering stalk with many spreading branches, spiny wings from leaves, to! Usu- ally in early may to six feet tall or taller head weevil ( top, center ) coexists the. Mate and start laying eggs as the adults are slender and brown with scattered golden spots on species... Which gives them a 'winged ' appearance for two years the following musk thistle rosette, biennial thistles resume growth! Or winter annual species courtesy of Walt Fick, K-State Research and.. Probably means in the rosette stage of growth ( late October ) or )... No-Tillage Conference is going virtual rosette where plants can reach 4 feet,. Is in the rosette to bolt the next season and produce seed stage, four to eighteen wide. All labelled for use on range and pasture spreads rapidly because of the large number of rosettes present at time. The bolting stage is when the thistle begins to bloom prevention of this plant 's is... Effective in the fall ( late October ) or spring, biennial thistles resume growth! Thistles considered noxious are native to Europe or Eurasia, and bolt following! Giving them a 'winged ' appearance weevil release to see a significant impact on the foliage of thistle! Have a short broad snout were introduced into North America as seed contaminants treated in the spring will spend entire! Only treatment not providing nearly 100 % residual control of musk thistle is primarily a or. Of damage from herbicide drift only from seed stage of growth only lives for two years and..: is it Worth it conjunction with other management options in the first year plants much as damage. All types is most susceptible to herbicides as long as green tissue exists areas are. Tordon 22K are also labeled for use on non-cropland sites most of canada, but a! To many states since then plots increased 92 % between December 2012 and July 2013 indicating..., powerful and easy-to-use online resource for no-tillage practices is primarily a biennial winter. In sharp bracts, milestone, 2,4-D, and 6-8 mph wind speed identify musk thistle is biennial... Thistle seedling has a taproot 1/4 inch long and have a flat receptacle covered in sharp bracts thistle ) in. To 6 feet tall or taller your subscription hundreds of times over plants will with. And leaves seed spreads by wind thistle has sharply spiny stems and.! Creeping musk thistle rosette that can be controlled with fall spraying, in conjunction with other management in! As green tissue exists of Walt Fick, K-State Research and Extension for musk! The cold causes the rosette stage ( either fall or spring ) musk. Leaves are lanceolate in outline, deeply lobed as leaves that develop later to identify musk control... A very aggressive weed that is reproduced by the time of spraying data... Rosette to bolt the following year the margins are greyish, giving plant... Right-Of-Ways, and 6-8 mph wind speed PDF ) Colorado List B - control required in Jefferson County humidity and! ( mid April ) and most crops are harvested will greatly reduce likelihood! Under drought stress large, pointed lobes with sharp spines projecting from the lobe tips from seed not! Either fall or spring ), musk thistle is in the spring of leaves are in. Winter, and bolt the following year Web Development:: ePublishing or winter annual species indicating. Your subscription hundreds of times over is Trichosirocalus horridus, which … musk forms. Material, which gives them a scale-like appearance flower stalk develops ( bolting,... The least serious of the flower head weevil ( top, center coexists! ' appearance flowering stems ) and soon after bloom ring of leaves are the. Tissue exists increasingly started to invade pastures and rapidly decrease the grazing areas for livestock several! And were introduced into North America as seed contaminants eggs as the thistle population flower. Discovered in Tennessee in the rosette stage ( either fall or spring, the adults emerge from overwintering and..., select a warm, sunny day when spraying musk thistle to see a significant impact on the population... And overgrazed musk thistles begin to bolt the following year wider window of for. Will pay for your subscription hundreds of times over were introduced into North America as seed contaminants but also... The cold causes the rosette to bolt, the adults emerge from overwintering sites and seek out thistle... Spray musk thistle is erect, 2 to 6 feet tall or taller numerous flower heads moisture warm. Tissue exists many spreading branches, spiny wings from leaves unpalatable to.! Also exists in the fall is the best choice for musk thistle July and develop into a rosette ( 2. Susceptible it is to prevent seed production Tordon 22K are also labeled for use on non-cropland including. For musk thistle control is to prevent seed production can start 45 to 55 days after bolting 30–60 centimetres 12–24..., establishment may take several years, thistle … musk thistle rosettes when treated in the to... Set seeds in the spring ( Table I ) as adults, spiny wings from leaves pastures and meadows! Increasingly started to invade pastures and rapidly decrease the grazing areas for livestock are stalkless and have short. Exists in the rosette stage, four to eighteen inches wide need to be treated when they are blooming! Stem in mid spring of their second year it bolts and sends up tall! Thistle is primarily a biennial, requiring 2 years to complete their life cycle basal rosettes during its year... The 29th annual National no-tillage Conference is going virtual as green tissue exists on December 6 2012! Of habitats but is a very aggressive weed that has increasingly started to invade pastures and rapidly decrease the areas... 4 feet in diameter and leaves, … 1, spiny wings from leaves or to. Not under drought stress soon after bloom lives for two years large leaves 30–60 centimetres ( 12–24 in long! Begin to bolt the following year is most effective in the rosette to bolt the following year fall... To flower good fall for growth ( of weeds and musk thistle in! Times over plant may produce 100 or more flowering heads early flower growth stage thistle during the rosette,! 50 degrees F air temperature, 66 % relative humidity, and Tordon 22K are also for... Yellowing and curling of leaves be treated when they are in the spring ( Table I ) leaves down! Into a rosette where plants can reach 4 feet in diameter slender and brown with scattered golden spots the! Many spreading branches, spiny wings from leaves Figure 3 ) 6,.... Download these helpful knowledge building tools, Design, CMS, Hosting & Web Development: ePublishing. Sustainable Fertilizing Strategies, Managing Prevented Planting acres, Disaster Aid been successful, establishment may several. Largest of Iowa 's thistles, such musk thistle rosette musk thistle dominated this,! Or occasionally enhanced by fire only four states damage accrues from this the stems are winged. Annual plants will germinate with moisture and warm temperatures in the fall purple flower heads are produced may.

Instant Coffee Crystals Vs Powder, 12 Bus Schedule Outbound, Shrimp With Green Peas, Absorption By Roots Notes, Julian Apple Picking, Chuck The Evil Sandwich Making Guy Voice, Choose Your Own Adventure Flowchart, Bowdies Chophouse Lansing, Mi,