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507-509 Rhoton Rd Noxious WeedsMG ma i 1 C& E Developments, LLC <cedevelopment05@gmall.com> Poison Hemlock - Rhoton Rd. Property 2 messages Alice Martin <alice.martin@co.thurston.wa.us> Wed, May 9, 2018 at 1:22 PM To: "cedevelopment05@gmail.com" <cedevelopment05@gmail. com> Hi Karen, Here are some materials to help with the poison hemlock. Attached is a fact sheet with prescriptions for applying herbicide, if you so choose; it also describes some other methods for controlling poison hemlock, including insect releases and things like that. Primarily our goal is to prevent the plants on your property from going to seed this year, and I can't really recommend the insect release for that as you need a much worse infestation for it to really work. I've also attached a map of the property where I've circled the area where I found poison hemlock (and the tent). I also drew a line showing the berm between the concrete company next door, Yelm Community Services, and your property, which is another hotspot for poison hemlock. As for timeline, I would expect the plants to flower within a week or so, and to set seed by next month. I would set a goal of at least spraying it by the end of this month. A systemic herbicide works best to kill the whole plant, from leaf to root, but even something to just kill the tops and prevent seed setting works. Even better than spraying is to excavate the entire plant, taproot and all, and dispose of it in plastic garbage bags. We offer free disposal of this noxious weed at our county transfer station. For the future, I would advise you that we have been working on this neighborhood for poison hemlock for many years. Almost every parcel in the vicinity has a record of poison hemlock, and at least some of them have set seed in recent years. This means that we can expect there to be a significant seed bank in the soil, and with every disturbance comes a potential opportunity for the hemlock to find a new spot. For example, I inspected a record recently where there had been 1 plant the previous year; the new owner scraped soil into a berm, which is now covered in poison hemlock. You are not alone in this fight! However, by continuing to control the hemlock where it is at, we can prevent further spread into other parts of the county. Young children have been known to put the leaves into their mouths and become very sick; consumption of the taproot has been the cause of at least one fatality in Pierce County in recent years. Once you have reviewed your choices, please let me know what your plan is to tackle the poison hemlock. I will make a note of it and follow up later on this summer to make sure that the treatment was effective. If you have any questions I am more than happy to help. Cheers, Alice M. Thurston County Noxious Weeds Dept. May 9, 2018 THURSTON COUNTY NOXIOUS WEED FACT SHEET Foison HCM10CL(Coniummaculatum) Description: Poison hemlock is a member of the parsnip or carrot family (umbelliferae). This species is a biennial, pro- ducing large rosette leaves during the first year of growth. ' During the second year the plant may grow to a height of up to 12 feet. Except for its size it closely resembles wild carrot, a common plant found throughout Thurston County. Poison hemlock has hollow, hairless stems (leaf canes) with purple blotches. It is a biennial, reproducing by seeds only. Leaves are fern like and up to 1 1/2 feet long. The flowers are white and develop into green, ridged seed capsules that eventually turn brown. Each plant is capable of producing up to 38,000 seeds, which can remain viable in the soil for up to 6 years. Impacts: The entire plant is toxic to humans and animals. It contains the poisonous alkaloid coniine and other alkaloids. Most poisoning occurs because the leaves are mistaken for parsley, the roots for parsnip and the seeds for anise. Poisoning of humans have occurred after the ingestion of seeds, leaves and roots and even as a result of blowing through the hollow stems when used as whistles or peashooters. The seeds, however, are the most toxic part of the plant. "Poison hemlock remains toxic for several years after being pulled, and it is wise not to leave the dead plants where they might be eaten by wild- life or children" (Parsons 1973). _ Control Options: Thurston County's Integrated Pest Management empha- sizes cultural, biological, and manual control methods to keep pests and vege- ' ' y' tation problems low enough to prevent damage. The strategy of Thurston County's IPM policy is to minimize the use of pesticides. ► Cultural / Habitat Follow-up planting of any bare or disturbed area is recommended to provide .. .;. a, =� r competition with hemlock seedlings that will emerge from the seed bank in the soil at infestation sites. i► Manual / Mechanical f i Hand removal is recommended for small infestations (for example 10 to 20 plants or more if the soil is loose enough to make them manageable). When {• pulling the plants, dig down and remove the entire taproot. Be sure to wear �. 'a gloves and to wash your hands after working with poison hemlock. Manual V'f `:{ = r control efforts can be successful, but we have found that the disturbance of soil r 4 resulting from manual removal methods encourages germination of seeds at ;;. infested sites. Solid carpets of _ — . hemlock seedlings are not un- common. Cutting the poison hemlock is an ineffective option for control, since the plants do not die and re -growth will occur, plants send up new seed stalks in the same season the cutting occurs. ■ Biological The Defoliating Hemlock Moth (Agonopterix alstroemeriana) is available and has been released in Thurston and other counties in Washington but results have been highly variable and almost completely ineffective in Thurston County. Additionally, biocon- trols are dependent on heavy densities of undisturbed host plants, and Thurston County's goal is to control all Poison Hem- lock wherever it is found. ► Chemical Spot spraying with an herbicide containing the active ingredient glyphosate (example: Roundup Pro®, Eliminator Weed and Grass Killere, etc.) can he used to treat poison hemlock effectively. Some glyphosate products have a supplemental labal for treating poison hemlock by an alternate method known as "stem injection". This method Is especially+ useful where there are sensitive plants nearby. One product known to have this supplemental labeling is Roundup Pro . Due to recent health reviews, Thurston County recognized some scientific studies have concluded the use of glyphosate products have carcinogenic potential. The risk of spot spraying with these products is considered to be low provided the applicator uses personal protection equipment which includes chemically resistant gloves in addition to long sleeve shirt, long pants, socks and shoes and all other label precautions are followed. Imazapyr (example: Polaris® or AlligareT"' Imazapyr 2SL) is also effective in controlling infestations of poison hemlock. Imazapyr is a non-selective herbicide and may damage or kill any other plants that it contacts, including grass. It may also leave persistent bare ground in the treatment area. This can be minimized by using only as directed, spraying at the recommended strength and no more than necessary to wet the surface of the leaves and stems. Products contain- ing the active ingredient imazapyr are considered "moderate in hazard" by Thurston County's pesticide review process for the potential for chemical mobility and persistence. Foliar applications: • For spot applications of either glyphosate or imazapyr, prepare herbicide by following label instructions at rates listed below. Spray each plant thoroughly on the stems and leaves, enough to be wet but not dripping. Spot application means the herbicide is applied only to the poison hemlock plants, and not on the surrounding plants or soil. • Glyphosate is non-selective, and will injure any plants that it comes in contact with, including grass. • Imazapyr is also non-selective, and will injure any plants that it comes in contact with. Do not use on lawns, walks, driveways or similar areas where roots of desirable vegetation may extend and be exposed to potential injury. Keep people and pets off treated areas until spray solution has dried. Hollow stem injection using glyphosate: • Individual poison hemlock plants may be treated by injecting up to 6 milliliters of a 5% solution of Roundup Pro® with a hand-held injection device directly into the hollow stem 10 to 12 inches above root crown. • Mark each plant when injecting it, to avoid retreating the same plant. The following instructions are for concentrated products which will be mixed down to a specified dilution rate. Similar products may be significantly different in strength. Be sure to read your label carefully, and make ad- justments to rates accordingly. Timing: Poison hemlock should be controlled whenever it is found when the plant is actively growing and prior to seed production. Monitor the area in following years to check for new plants from the existing seed bank. Pollinator Protection: To minimize negative impacts to bees and other pollinators, treatment prior to blooming is recommended. Removal of flowers before treating may be an option in some circumstances. Use of the injection method would also have minimal effect on pollinators. If treatment must occur during the blooming period, try to spray early or late in the day or on cloudy, cool days when pollinators are least active. READ AND FOLLOW ALL LABEL DIRECTIONS AND RESTRICTIONS. Obey all label precautions including site Product/Method Rates Mix Glyphosate 1 Spot Foliar Roundup Pro° 2% Add 2.6 oz (5.2 Tablespoons) concentrated product per gallon of water. Eliminator Weed & Grass Killer® Inject one leaf cane per plant 10 - 12 inches above root crown with 6 mL of a 5% Glyphosate / Injection 5% solution of this product. Use a cavity needle and push it into the stem center, then Roundup Pro slowly remove it as the product is injected into the stem. Imazapyr I Spot Foliar Polaris® 2% Add 2.6 oz (5.2 Tablespoons) concentrated product per gallon of water. AlligareTm Imazapyr 2SL specific and safety measures. Always use personal protective equipment that includes coveralls, chemical resistant gloves, shoes plus socks, and protective eyewear. Use of brand names does not connote endorsement and is for refer- ence only; other formulations of the same herbicides may be available under other names. Information provided is cur- rent as of the date of the fact sheet. Pesticide product registration is renewed annually. Product names and formula- tions may vary from year to year. REFERENCES: Thurnon County Noxious Weed Comrol University of Illinois Extension IPM Bulletin, Article 8/May 19, 2006; httD:/1 9605 Tilley Redd S. bullet*tn.ipm.illiriois.edu/artiole.Dhp?id=52,4 Ofympio, WA 98512 "Indiana Plants Poisonous to Livestock and Pets" Purdue University Co- Phone: 360.786•$$576 operative Extension Service Fact Sheet; -. - �'� TTY/TDD - Call 711 or 7.840-833-6388 Highly Toxic Poison Hemlock, a Threat in Newly Urbanized Areas" by TiiUR5T011 COUNTY tcweeds r0.thurslan,wn.us Mauricio Espinoza, Ohio State University Extension ® ww-xo.Ihue non.wo.w/1cw0cis USDA/ARS Poisonous Plant Research Laboratory Fact Sheet 415; Revised February, 2017 BMW P;A 44 vrp NOW BMW P;A