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Musk thistle

Consider the warm dry winter that’s just ended and how with a bit of Spring moisture, weeds will soon make their annual appearance in your garden and surrounding landscape.  Whether you’re a local veteran of yearly weed battles; a new resident from out-of-state or someone who’s just ‘moved up the hill’ from the more urban surroundings of the Metro area, facing weeds in the foothills can be daunting!   As if gardening at altitude isn’t challenging enough, the dandelions and diffuse grassy clumps of lower elevations are for the rookies.  You’ve just entered the big leagues of weed wrangling!  Consequently, this is a good time to dust off your garden tools and read up while we highlight steps on wrangling popular local offenders.  Let’s review the basics from weed identification to eradication and control.   Additionally, as foothills residents, we shouldn’t forget that there are many state agencies that can help with the identification of the weed you’re looking at. (See resources listed below). After all, you can’t effectively eradicate or control something you know nothing about, right?? 

First, you must learn to recognize the weed you are trying to wrangle. Is it a native plant growing here before you arrived, that simply grows where you don’t want it to grow, or a non-native invasive plant with a potentially harmful impact if allowed continued growth?  Consult Colorado’s Department of Agriculture lists of Noxious Weeds (https://www.colorado.gov/pacific/agconservation/noxious-weed-species) that can help pinpoint and inform you of things you need to know about eradication, management and research mandated from state to local levels.  Also, in the near future, the Evergreen Farmer’s Market, staffed by Jefferson County Master Gardeners, will have their annual Weed Clinic Day on July 11th this year.  It is a one day partnership with the Evergreen Audubon Group where you can bring your own weeds, see their samples and learn about what you need to do for eradication. Be proactive in refreshing your knowledge on how and when certain weeds may develop.  Is it a winter or summer weed? Think about how seeds will spread; the growth habits that may include spreading along the ground with runners or climbing up stationary landscape elements, including other plants.   These are all some of the varying traits of a weed’s growth pattern and life cycle.

Secondly, wrangling or controlling is more beneficial when you know specific traits and can develop your best management practices.  While our weeds may seem too haunt you year-round, perhaps yours is simply an annual, perennial or biennial weed not being controlled effectively.  Knowing this alone will assist you with more effective control methods.  That guaranteed home recipe from your neighbor for vinegar based weed killer is not a winning formula.  Are you in need of some gentle, quiet time?  Grab a container and go outside with your favorite weeding tool and simply work on manual eradication.  Weed whackers may do the job quickly on grasses but can also help to spread seeds and destroy wildflowers if you do it at the wrong time! A critical note to include here is to choose wisely and do your research if you go the route of chemical or biological control. 

Cheat grass taking over
Lastly, for long term management, be patient, have a plan, research and talk to knowledgeable, experienced people who know effective control methods.  Don’t just reach for the long-term bottle of weed control on your next trip through the store. We live in a beautiful environment and many animals and beneficial insects rely on flowers for pollen, food sources and other elements to sustain their lives. Managing and controlling weeds on your property with a thoughtful plan contributes to the enjoyment of your garden and landscape.  It’s crucial for all of us, especially when considering wildfire mitigation.  I wish happy wrangling to all.  May your efforts be rewarded with bountiful outdoor pleasure this Spring, Summer & Fall.

Here’s my supplemental reference list of easily recognizable offenders, plus 5 general resources for more information.
Noxious weeds:
Bindweed- Perennial w/extensive root systems. Grows in dense, low mats.  Sometimes called Wild
Morning glory. Seeds can be viable for half century!
Cheat Grass- Several varieties are among the Brome/Grass family. Seed pods germinate in Fall, drop and
overwinter. Already we are seeing new shoots come up.
Common Burdock – biennial, grows to 10’ tall. Burs stick to animals and clothing.
Knapweed- Several varieties are found, all from Sunflower family.  They include Diffuse, Spotted and
Russian.
Mullein (Common)- Found in many open fields. Tall flowering stalks with yellow flowers.
Myrtle Spurge- low growing perennial in clumps. Easily spread in shade among rocks. Sap can be
irritating to skin.  Several varieties are found, all invasive.
                                Oxeye Daisy –creeping perennial with attractive white flowers.
Thistle- Three are biennial ( Bull, Musk and Scotch), and one (Canada) is a creeping perernnial that is hard to eradicate.  
Yellow Toadflax- Perennial often mistaken as a wildflower. Reproduces by seed and underground
rhizomes.  Close cousin is Dalmatian Toadflax, both highly invasive.

Nuisance weeds:
Broadleaf plantain- A fibrous rooted perennial.  Seed stalks a favorite of birds and small
animals. 
Shepherd’s Purse-Mustard family member.  Early Spring bloomer.  Generous seed production.
Sagewort- Perennial native of Europe, from Aster family.  Favorite of rabbits and some birds.
Mallow- Includes Common and Velvet Leaf varieties. Originates from Europe and Asia.
Dandelions- Crucial in supporting bees due to early Spring blossoms and pollen. Treat them as
wildflowers and enjoy the color!!
Pennycress (Field) – Annual w/large taproot. Oils researched as potential bio-fuel in mid-west. Attracts
small bees and flies.


 Resources with good colored pictures for identification:
www.ext.colostate.edu for Noxious Weed Management and Pocket Guide. 2013.  Good, basic management guide and further website listings.
www.colorado.gov/pacific/agconservation/noxious-weed-species for Noxious Weed species (A,B,C Lists).
http://jeffco.us/weed-and-pest/weeds/noxious-weed-information/for Noxious Weed Identification and Control . Very user friendly listing by name or flower color.
Weeds of the West, Tom Whitson, editor, 2009 Revised edition, Western Society of Weed Science.
Can be cumbersome with a scientific weed family key for use, but easily referenced common name index and glossary. Beware that many plants are native plants (that can be problematic in pasture/rangeland situations).
Garden Smart Colorado A Guide to Non-invasive plants for your garden, Colorado Weed Management Association, 2012.  Great resource for basic alternative ornamental plantings, including invasive plant notations.

by Google