War on Weeds ! Cindy A. Kinder University of Idaho, Camas County Extension, Fairfield, Idaho

Definition of Weeds  A plant that is growing were it is not desired.  Noxious weeds are harmful/injurious to the land, livestock and/or people by state law.

Weedy Conditions  Disturb the soil or ground cover  Leave an opening for weeds to germinate  Once established, prolific seed producers  Seeds can lie dormant for many decades Long term commitment to weed management

 Affect everyone –Aesthetic & visual values –Decrease functions of natural ecosystem –Displace native vegetation –Decrease wildlife habitat –Increase erosion & stream sedimentation –Reduce recreational value Weeds

The War  Land managers –Forest service, –BLM, –Parks & recreation –Private Wildlife habitat, range production, recreation, timber

Weed Identification/education Is it a weed ?

Know Plant Life Cycles  Annuals- grow, flower, seed then die in one growing season ( ex. Downy brome).  Biennials- 1 st season- rosette & taproot. 2 nd season- flowers, produces seed & dies. (Ex. Bull thistle).  Perennials – live for more than 2 years. Reproduce by roots, rhizomes, seeds etc. (Most noxious weeds).

Controlling Weeds  Prevention. –Cheapest, –Watch roadways, fence lines, clean machinery, buy clean seed, –Composting manure – gets most not all.  Mechanical. –Hand-pulling, mowing, burning, cultivation, plowing. –Disrupts root system & plants dry out before re- root.

 Cultural. –Land & water management. –Crop rotation – peas, winter wheat, spring barley. –Crop competition - nurse crop. –Optimum soil fertility.  Chemical. –Timing critical. –Select best chemical for situation. –Don’t over dose, need to kill the root also. Controlling Weeds

 Biological. –“Natural enemy.” –Insects, goats, sheep.  Integrated approach. –Works best. –Most effective. Controlling Weeds

Controlling Annuals  Mechanical –Mowing, no! –Burning, may not kill seeds –Tillage, yes!  Chemical –Only need to kill shoots –Easiest at seedling stage

Controlling Biennials  Mechanical –Tillage  Chemical –Only need to kill shoots (post emergence) –Easiest at seedling stage –Apply at rosette stage, before bolting

Controlling Perennials  Mechanical –Mowing, yes! (For many)  Can stimulate new shoot growth, field bindweed. –Tillage, no! (For many)  Can be effective for leafy spurge.  Chemical –Apply  Seedling stage  When food reserves depleted (after rapid growth)  NOT at mature stage  Choose chemical that moves to the roots

Management Plan  List of problem weed (s) –Know the life-cycle and how they spread  Methods of controlling

Management Plan  Map location and number of acres Morning Glory Diffuse Knapweed

Management Plan  Budget available  Available manpower  Time commitment –Chemical/biocontrol  Joint agreements –Neighbors  Re-vegetation  Evaluate list & determine plan of action

Knapweed Identification Spotted Diffuse Russian

Knapweed Identification Spotted DiffuseRussian

Diffuse Knapweed  Perennial/biennial  Reproduce-seeds  Treatment –Yearly tillage may work –Biocontrols  Moth  Root weevils  Seed head weevils  Seed head flies –Chemical  Tordon at rosette stage in fall  Tordon, 2,4-D stop flower production  Curtail, stinger, Transline, Banvel

Spotted Knapweed  Perennial  Reproduce-seeds  Treatment –Cultural  Tillage – NO  Mowing – reduce seeds  Hand pulling – some regrowth –Biocontrols  Seed head moth  root weevils -Chemical  Tordon- rosette – prebud & in fall  Stinger, Banvel – early bud  Broadleaf control – not after flowering

Russian Knapweed  Perennial  Reproduce- seeds & rhizomes  Treatment –Cultural  Tillage – NO  Mowing – reduce seeds  Hand pulling – some regrowth –Biocontrols  Seed head moth  root weevils -Chemical  Tordon- rosette – prebud & in fall  Stinger, Banvel – early bud  Broadleaf control – not after flowering

Leafy Spurge  Perennial  Reproduce: seeds and spreads with shoots  Extensive root system –Recover from physical/chemical treatment  Milky latex in plants  Treatment –Mechanical - not really –Biocontrol  Sheep/goats  Flea beetles –Chemical  2,4D or Picloram plus 2,4-D  Tordon with 2,4-D at full bloom  Plateau in the fall

Rush Skeletonweed  Perennial  Reproduces by seeds and re- growth from roots  When broken exude a milky latex substance  Treatment –Cultivation  Ineffective, may cause more spread –Biocontrol  Rust, mite, and midge –Chemical  Difficult to control –Tordon,2,4-d, –Stinger, Banvel,

Hoary Cress (White Top)  Perennial  Reproduces by seeds and rhizomes  Treatment –Chemical  Early growth stages  2,4-D amine, LV ester  Escort, Telar

Canada Thistle  Perennial  Reproduces by seed but spreads by rhizomes  The flower heads are either male or female  Treatment –Cultivation  No!! Cause to spread more –Biocontrol  Weevils –Chemical  Stinger- rosette stage  Curtail – before bud stage  2,4-d

Summary  War on weeds  Weed identification  Plant life cycles –Annuals, biennials, perennials  Control methods –Prevention mechanical, cultural, chemical, biological, integrated  Management plan –List of priority weeds, mapping, budget, time commitment  Knapweed, leafy spurge, rush skeletonweed white top, Canada thistle,

Your Plan of Action  Identify & map problem weeds  List ways to control problem plants  List budget limits  List people availability  Set short and long term goals Just do it