Noxious Weeds

Lyon County, Kansas

Lyon County Noxious Weed Department

3000 West South Avenue
Emporia, KS  66801
Fax: 620-340-6369
Mobile: 620-412-7722



The purpose of this page is to assist property owners in Lyon County with information on the Noxious Weed Law, noxious weeds and the methods to control them. The control of any weed depends a great deal on early detection of it’s presence. This page was assembled to aid in that process. If you discover noxious weeds, or you have questions about weed management you may contact us at the address listed above.

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Lyon County Noxious Weed department provides herbicides to Lyon County residents for use on Noxious Weeds in Lyon County at 25% off retail cost.

Brand Name Chemical Name Unit Size Type Restricted Use
Escort XP (Metsulfuron) 8 oz bottle (granular) No
Clean Anime (2,4-D) 2.5 gal jug (liquid) No
Remedy Ultra (Triclopyr) 1 gal jug (liquid) No
Mad Dog Plus (Glyphosate) 2.5 gal jug (liquid) No
Plateau (Imazapic) 1 gal jug (liquid) No
Tordon 22k (Picloram) 2.5 gal jug (liquid) Yes

Noxious Weeds

Field Bindweed

Description — This perennial reproduces by seeds and rootstocks. The root system is extensive and may go down 20 to 30 feet. Smooth, slender stems, 2 to 7 feet long, twine or spread over the surface of the ground. Leaves are ovate with spreading basil lobes. White or pink, funnel shaped flowers, about 1 inch across, grow singly in the leaf axils. The flower stock has two bracts, .5 to 2 inches below the flower, which distinguishes this weed from hedge bindweed . Egg-shaped seed pods usually contain 4 seeds which are dark, rough, brownish gray, about .13 inch long with 1 rounded and 2 flattened sides. (June-Aug)

Adaptation — Found in cultivated grounds, fields, and roadsides, field bindweed is able to persist d spread in all non-cultivated areas and under most cropping systems. It can be found in all counties in Kansas . It has been fought by farmers and landowners since the early 50’s without much progress. Field Bindweed seed has a very hard coat which enables the seed to remain the soil for long periods of time with sporadic germination.

Management options

1. Prevention —Clean crop seed before planting to remove bindweed seed and other weeds. If possible do not feed bindweed seed- infested feed to livestock or if it is fed, do not spread manure on bindweed-free land. Clean harvesting and other machinery before leaving infested fields.

2. Cultural Control — field Bindweed can be reduced by use of appropriately timed tillage and planting of competitive crops. Hoeing in non-cropland areas such as gardens, flower beds and forestry plantings at regular intervals of 10 to 14 days can control bindweed effectively.

3. Biological Controls — None

4. Recommended Treatments:

2,4-D .5 gallon/acre

Roundup (Glyphosate) 1.0 gallon/acre

Tordon 22k (Picloram) 1 to 2 quarts/acre

Oust (Sulfometuron) + 2,4-D – 2 to 8 oz Oust + .25 gallon 2,4-D/acre

Johnson Grass

Description — Upright perennial grass, reproducing by rhizomes and seeds. Well adapted to compete with crop plants. Stems up to 6 to 8 feet high or more, from a freely branching fibrous root system, which produces extensive rhizomes within six weeks of generation. Leaves alternate, simple, relatively wide and long. Spikelets 1-flowered, in groups of 3, in large open panicles. Fruit a caryopsis or grain, finely striate, reddish-brown with two knobbed rachillae extending upward from the base of the seed. Flowers from May until frost and seeds to frost.

Adaptation — Found especially on rich soil, johnson grass is a common weed in in cropland, roadsides, ditches, and field margins. Troublesome in crops on overflow bottoms, it often grows in moist ground. The largest acreage of johnson grass infestation in southeast and southwest Kansas.

Management options

1. Prevention —reduce infestations by planting seed free of johnson grass seed, using livestock feed free of this noxious weed, and cleaning machinery before leaving infested areas.

2. Cultural Control — Infestations by be reduced by planting small grain and using intensive tillage as needed after harvest. Hoeing can be used as needed to control johnson grass in yards, flower gardens and among shrubs. Mowing as needed and intensive grazing can be used to control this noxious weed in established grass.

3. Biological Controls — None

4. Recommended Treatments:

 Roundup (Glyphosate) .5 gallon/acre

Oust (Sulometuron) 6 to 12 oz/acre (2 to 5 oz/acre for short term control)

Roundup(Glyphosate) + Oust (Sulfmeturon) – 2oz Oust + .5 gallon Roundup/acre

Musk Thistle

Description– Usually this thistle is a biennial, but sometimes it is a winter annual or annual. Stems are erect, spiny with spiny wings, and 3 to 6 feet tall; the lower portion is branched. Stems and branches are densely covered with short hairs. Spiny, coarsely-toothed leaves alternate down the stem. Flower heads are as much as 2” across, on the ends of long, nearly naked stems, frequently drooping or nodding. The flowers are purple or lavender; spiny-tipped bracts surround the head. Seeds are about .19 inch long, glossy yellowishbrown; pappus is hairlike.

Adaptation –Musk thistle is locally abundant to moderately infrequent in pastures, prairie ravines, hillsides, open wooded stream valleys, fields, roadsides and waste areas.

Life History –Musk Thistle germinates in the spring and fall and spends 90 percent of its life cycle in the rosette stage. Most plants bolt in May-June and flower during the summer. Musk thistle is a prolific seed producer and readily invades site with disturbed soils. Seedling mortality is the greatest in late spring and summer. Plants that germinate late in the fall often have greater mortality, lower growth rates, flower later and produce fewer seeds/plant.

Management Options

1. Prevention— Reduce new infestations by planting weed free seed, using livestock feed free of Musk thistle seed, and cleaning equipment before leaving infested areas.

2. Cultural and Mechanical Practices— Mowing, hand cutting, hand digging and the removal of heads are practices for control of musk thistle.

3. Biological Control— Biological controls available includes insects, parasites and disease causing organisms. For current recommendations contact Kansas State Board of Agriculture.

4. Recommended Treatments:

 2,4-D .5 gallon/acre

Roundup (Glyphosate) 1 gallon in 2 gallons water to get a 33% solution—apply with a roller

Tordon 22k (Picloram) 6 to 8 oz/acre for fall treatment

Tordon 22k (Picloram) + 2,4-D — .5 pint Tordon + .25 gallon 2,4-D/acre for spring treatment

Escort (Metsulfuron) + 2,4-D — .5 oz Escort + .25 gallon 2,4-D/acre

Sericea Lespedeza

Description — Sericea Lespedeza is a perennial with erect stems up to 5’ tall and small hairs laying flat along the ridges on the stem. The leaves, with 3 leaflets, are less than 1” to 1 1/2” long and a 1/4” to 1/2” wide with larger leaflets on the lower portion of the stem. The leaves are flattened on the outer end with small flat hairs on the lower surface. Flowering occurs from mid or late July to October and may be tinged with purple but always dry to yellow. The tannin content of the plant also increases during the growing season making it unpalatable to livestock.

Adaptation — Sericea Lespedeza is found primarily in native rangeland, waste areas, CRP and roadsides. Sericea Lespedeza is found throughout Lyon County but has its largest infestations south of Olpe. With other infestations of significant size found around Reading and Americus.

Management options

1. Prevention —Inspect all pastures and rangeland in July, August and September. Early detection of the presence of Sericea Lespedeza is essential to economical control.

2. Cultural Control — Sericea Lespedeza is found primarily in native rangeland, waste areas, CRP and roadsides. Sericea Lespedeza is found throughout Lyon County but has its largest infestations south of Olpe. With other infestations of significant size found around Reading and Americus.

3. Recommended Treatments:

Escort (Metsulfuron) .5 oz/acre Fall treatment

Remedy (Triclopyr) 1 pint/acre Spring treatment

Goats: 6-8 goates/acre first year, 4-6 goats/acre second year, 2-4 goats/acre third year

Noxious Weed Law

Director has knowledge of noxious weed infestation.

1. General notice in newspaper to all landowners.

  • Legal Notice
  • Treatment
  • Prosecution
  • Fine upon conviction
  • Diversion Agreement

2. Official Notice.

  • Legal Notice
  • Treatment
  • File Charges
  • Fine upon conviction
  • Diversion Agreement

3. File Charges.

  • Fine upon conviction
  • Diversion Agreement