Creeping thistle, Cirsium arvense, management

Transcription

1 Creeping thistle, Cirsium arvense, management

2 Outline Iden4fica4on and Biology Where are thistles located in Alaska Preven4on Your first priority Spa4al control strategies Integrated Pest Management (IPM) techniques

3 Biology and Iden4fica4on Creeping perennial 1 4 feet tall Spines on leaves Flowers ½ ¾ inch purple or white Leaf underside has soo wooly hairs Roots are deep Roots Image courtesy Purdue University hrp://

4 Similar Species Bull thistle has spiny winged stem, 1 2 inch wide flowers Na4ve thistles e.g. edible thistle, lack winged stem Creeping thistle no winged stem and smaller flowers Edible thistle, Cirsium edule, na4ve to southern por4ons of Southeast Alaska Bull thistle, Cirsium vulgare, invasive, with scarered popula4ons. No4ce spiny winged stem Images courtesy Eric Coombs, Oregon Department of Agriculture, bugwood.org

5 Impacts Reduc4on in farm produc4on Creates monocultures Generally inedible for wildlife except birds will eat seed Invades natural areas Beaches Wet meadows Grassy areas Forest edges Top image courtesy Alaska Natural Heritage program, borom image Bonsak Hammeraas, Bioforsk Norwegian Ins4tute for Agricultural and Environmental Research, Bugwood.org

6 Thistle loca4ons in Alaska Map from hrp://aknhp.uaa.alaska.edu/maps/akepic/

7 Thistle loca4ons Interior Map from hrp://aknhp.uaa.alaska.edu/maps/akepic/

8 Thistle loca4ons, Southeast Map from hrp://aknhp.uaa.alaska.edu/maps/akepic/

9 Thistle loca4ons, Southcentral Map from hrp://aknhp.uaa.alaska.edu/maps/akepic/

10 Thistle loca4ons, Anchorage Map from hrp://aknhp.uaa.alaska.edu/maps/akepic/

11 Preven4on Poten4al contaminant of: hay/straw Feed Seed Gravel/fill Equipment Long lived woody ornamentals

12 Preven4on U4lize cer4fied weed free products, e.g. hay/straw and gravel Clean equipment Time mowing opera4ons Write in contracts to control up to three years aoer projects e.g. construc4on Use locally produced seed if possible Inspect ornamentals or use bare root transplants

13 Control strategies Communi4es with new infesta4ons Eradicate E.g. Kenai Peninsula, Steven s Village Communi4es with well established infesta4ons Control/ contain Focus on not spreading to adjoining areas Remove from sensi4ve habitats Reduce numbers and density

14 Control Strategies using IPM Integrated Pest Management (IPM) Examines biology Iden4fies vulnerabili4es Addresses sensi4ve issues Uses mul4ple techniques to manage situa4on Increases success

15 Control Strategies using IPM Deep rooted perennial Heavy seed produc4on once per year Creeping root system that reproduces with fragments Grows in a variety of habitats Roots Image courtesy Purdue University hrp:// other courtesy, UAF CES, Bugwood.org

16 Control Strategies using IPM Digging Could work with small isolated infesta4ons Get all of roots! Big infesta4ons use heavy equipment Roots Image courtesy Purdue University hrp://

17 Control Strategies using IPM Covering Solariza4on Has not been tried in AK Must monitor beyond borders of weed barrier Root runners may extend well beyond border of cover

18 Control Strategies using IPM Mowing In healthy grasses can decrease density Will prevent seed set if done mul4ple 4mes Should be done in early July and again in late summer Will not eliminate Thistles should be mowed before flowers are fully exposed as seen on leo.

19 Control Strategies using IPM KILL THE ROOTS Herbicide Needed for eradica4on Generally spring and/or fall applica4ons Fall applica4ons work well aoer summer mowing

20 Control Strategies using IPM Spring new shoots are sensi4ve Late summer or fall shoots are transloca4ng carbohydrates to roots Systemic herbicide moves with carbohydrates

21 Control Strategies using IPM General herbicide protocol Early July Mow September Apply herbicide (before heavy frost) Do not disturb or mow aoer herbicide applica4on Image courtesy UAFCES, Bugwood.org

22 Herbicide considera4ons Generally use highest label rate Monitor 4me between applica4on and symptoms If density is not reduced vary the rate likely decrease it Or use a different chemical

23 Herbicide for roadside, hay/pasture or natural areas Aminopyralid product E.g. Milestone Selec4ve kill broadleaves Can damage trees if applied to root zone Not labeled for use on ornamentals or landscapes Should not convert farm land to potatoes for several years aoer use

24 Herbicide for roadside, hay/pasture or natural areas Clopyralid product E.g. Transline Selec4ve kill broadleaves Will not damage trees if applied to root zone Not labeled for use on ornamentals or landscapes Should not convert farm land to potatoes for several years aoer use

25 Herbicide for landscapes 2,4 D, MCPA, Triclopyr and/ or Dicamba E.g. Escalade2 (2,4 D) Horsepower (MCPA) Selec4ve kill broadleaves Will not damage trees if applied to root zone Most products labeled for use on landscapes/lawns Some (Escalade2) are labeled for ROW too Generally available

26 Herbicide for most sites Glyphosate E.g. Roundup and Aquamaster Non selec4ve Apply by spot spraying only Typically use with aqua4c formula4ons near water (e.g. Aquamaster) Infesta4ons near water should be treated with aqua4c approved herbicide and surfactant. Creek runs through right side of this picture.

27 Remember THE LABEL IS THE LAW Always read and understand the label

28 Adjuvants and Surfactants Recommended for most products Helps product contact plant and absorb by breaking water tension DEC typically requests use of Washington state approved hrp:// programs/wq/pes4cides/ regpes4cides.html Surfactants can be the most toxic component Washington State Aqua4c approved surfactants are tested for toxicity to aqua4c organisms Use these near water sources Others can be used at upland sites

29 Biocontrol Insects Insects not effec4ve for eradica4on Will prevent some seed produc4on Need >1 acre infesta4on Infesta4on can t be disturbed May be more effec4ve in combina4on with chemical applica4on Top thistle stem mining weevil, and borom thistle bud mining weevil. Photos courtesy Alec McClay, McClay Ecoscience, Bugwood.org.

30 Biocontrol Grazing Some animals will eat Works like mowing May reduce coverage Eradica4on unlikely Other considera4ons Soil compac4on Grazing desirable veg. Containing animals Care to not spread Photo courtesy USDA ARS Photo Unit, USDA Agricultural Research Service, Bugwood.org

31 Outreach needs Many infested areas are new People do not recognize severity of problem Encourage management Encourage repor4ng Encourage them to contact CES Raise awareness of area management efforts

32 List of Links hrp://aknhp.uaa.alaska.edu/botany/akepic/ Maps and informa4on for exo4c and invasive plants hrp://dec.alaska.gov/eh/pest/index.htm Pes4cide regula4ons and informa4on for Alaska hrp:// To search for pes4cides registered in Alaska hrp:// To search for up to date pes4cide labels hrp:// To see adjuvants/surfactants registered in Washington for use near water hrp:// For pest iden4fica4on support For state regulated weeds informa4on and Anchorage area strategic plan for thistle management