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Biology, Ecology and Management of Eurasian Watermilfoil (Myriophyllum spicatum L.)

Wednesday, April 7th, 2010

Get this great booklet from MSU about Eurasian Watermilfoil

Eurasian watermilfoil is a submersed aquatic plant that forms dense tangled beds that can competitively displace submersed native plant communities, reduce recreational qualities of water bodies, reduce water flow, clog industrial, agricultural, and drinking water supplies, and negatively impact fish and wildlife. If was first reported in Montana in Noxon Reservoir (Sanders County) in 2007. Plants primarily spread through stem fragmentation. Water recreation (primarily boats and boat trailers) is the predominant vector of long distance spread. After prevention, early detection and immediate action to contain and eradicate infestations are the most important management actions for Eurasian watermilfoil in Montana.

Download the booklet from MSU Extension now.

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Biology, Ecology and Management of Hoary Alyssum (Berteroa incana L.)

Monday, April 5th, 2010

MSU newest publication is now available.

Hoary alyssum is an exotic annual to short-lived perennial forb designated as a noxious weed in Montana since 2008. Toxicity to horses has been reported when green or dried forage is contaminated by more than 30 percent. It can proliferate in forage crops, pastures, and rangelands and rapidly fills in areas disturbed or overgrazed. Maintaining healthy stands of vegetation and reseeding after major disturbances are the best ways to prevent establishment. Herbicides are an effective control option, and repeated applications may be necessary to treat plants that emerge throughout the growing season.

Download this booklet from Montana State University Extension.

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Biology, Ecology and Management of Blueweed (Echium vulgare L.)

Monday, April 5th, 2010

MSU has done it again!   A new publication about Blueweed.

Blueweed (Echium vulgare), a member of the Boraginacae family, was introduced from southern Europe and is now widely distributed throughout North America. It is a biennial to short-lived perennial. Blueweed has bright blue flowers with pink-to-red stamens and is covered with bristly hairs. It reproduces by seed only. This species is typically found in disturbed areas and overgrazed range or pastureland. It thrives in sandy, well-drained soils with low nutrient levels and tolerates dry conditions. It has also been found in irrigated, well-maintained pastures. The plant is not considered palatable to livestock, and it has toxic alkaloids that can cause liver failure. Early detection of new plants is very important. Small infestations can be managed by hand-pulling or digging, while larger infestations can be treated with herbicides.

Download your copy of this 12 page full color booklet.

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Compatibility of Seed Head Biological Control Agents and Mowing for Management of Spotted Knapweed

Monday, April 5th, 2010

Authors: Jim M. Story, Janelle G. Corn, and Linda J. White

Summary: Seed head insects, primarily the seed head fly, Urophora affinis, and the seed head weevils, Larinus spp., are reducing spotted knapweed seed production by about 94% in most areas of western Montana. Studies were conducted on the compatibility of seed head biological control agents and mowing for management of spotted knapweed.  Our study demonstrated that mowing of spotted knapweed in the spring and early summer can result in the growth of secondary flower buds which escape attack by seed head biocontrol agents, thereby allowing the knapweed to produce a nearly-normal complement of seed.  Therefore, we conclude that the historical practice of mowing spotted knapweed during the spring and early summer with no follow-up mowings should be avoided if large populations of seed head biocontrol agents are present.

Download a copy of the research article.

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Oxeye Daisy: Indentification, Biology & Integrated Management

Wednesday, March 24th, 2010

This MontGuide describes oxeye daisy biological and ecological characteristics. It also provides mechanical, cultural and chemical management options to control this species.

Click to download load this publication for Montana State University Extension publications.

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Influence of Seed Head-Attacking Biological Control Agents on Spotted Knapweed

Wednesday, March 24th, 2010

Complete Title: Influence of Seed Head-attacking Biological Control Agents on Spotted Knapweed Reproductive Potential in Western Montana over a 30-year Period

Authors: Jim M. Story, Lincoln Smith, Janelle G. Corn & Linda J. White

Summary:  Studies were conducted on the impact of seed head insects on spotted knapweed reproductive potential in western Montana over a 30-year period.  Results indicated that seed head insects are reducing seed production by about 94% in many areas of western Montana.  The reduction of knapweed seed production has resulted in a 98% reduction in the knapweed seed bank which, in turn, has contributed to the decline of knapweed in these areas.  Of the seed head insects, the fly, Urophora affinis, and the weevils, Larinus obtusus and L. minutus, are having the greatest impact on knapweed seed production.  The current decline of spotted knapweed in many areas is likely due to the impact of the seed head insects on the knapweed seed bank and the effects of the root weevil, Cyphocleonus achates, on mature plants.

Download a copy of the research article.

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Leafy Spurge: Biology, Ecology and Management

Monday, March 15th, 2010

Authors: Kim Goodwin, Roger Sheley, Robert Nowierski and Rodney Lym

Summary: Identification, life cycle, distribution, physical control, plant competition, grazing management, biological and chemical control, suggested management plan. 25 pages. 12 color photos, distribution map for U.S. and southern Canada, tables, graphs and appendix detailing habitat requirement, biology and collecting suggestions for currently approved insect biocontrol agents.

Click to download load this publication for Montana State University Extension publications.

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Decline of Spotted Knapweed Density in Montana with Large Populations of the Root Weevil

Monday, March 15th, 2010

Full Article Name: Decline of spotted knapweed density at two sites in western Montana with large populations of the introduced root weevil, Cyphocleonus achates (Fahraeus)

Authors: J.M. Story, N.W. Callan, J.G. Corn, L.J. White

Summary:  Spotted knapweed plant density was monitored over a 11-year period (1993-2004) at two sites in western Montana where the root weevil, Cyphocleonus achates was released.  Spotted knapweed density declined significantly over time at both sites (99% and 77%, respectively), after C. achates numbers increased dramatically at both sites.  The current decline of spotted knapweed in many areas is likely due to the effects of C. achates on mature knapweed plants and the impact of the seed head insects on the knapweed seed bank.

Click here to download and read the complete article.

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Learn to Identify Hawkweeds

Monday, March 1st, 2010

Montana State University Extension has published a great 12 page booklet with information that will allow you to identify the different Hawkweeds found in Montana.

This publication includes descriptions, photos showing the details of what to look for in the different lifestages of this plant.

It is free from MSU extension.  Download a copy here today.

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MSU Montguide: Orange Hawkweed and Meadow Hawkweed Complex

Monday, March 1st, 2010

MontGuides are self-learning resource from Montana State University Extension.

“The hawkweeds are a very large genus of plants with approximately 25 species in North America. Hawkweeds are members of the sunflower  family and are closely related to dandelion, chicory, prickly lettuce and sowthistle. Like some of their relatives, hawkweeds can rapidly colonize and dominate forest meadows, pastures and roadsides. In addition to reproducing by seeds, hawkweeds are capable of spreading by rhizomes, stolons and adventitious root buds. These methods of vegetative reproduction and a tolerance for sites with low productivity are probably responsible for the ability of these plants to quickly establish and dominate new areas. ”

Download the MontGuide including information on the origin, identification, impacts and information on management of the hawkweed.

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