Erosion and Storm Water Management Unit Mail Stop John Ireland Blvd. St. Paul, MN 55155

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1 Minnesota Department of Transportation Office of Environmental Stewardship Erosion and Storm Water Management Unit Mail Stop John Ireland Blvd. St. Paul, MN Memo Office Tel: Fax: TO: FROM: District 2 Design Brett Troyer, P.E. Erosion Control Engineer DATE: April 14, 2014 SUBJECT: Turf Establishment Recommendations for District 2 Please distribute this memorandum to personnel designing projects in your district including consultants. This letter is the turf establishment recommendations for projects in DISTRICT 2 and will remain in effect until superseded at which time a new letter with necessary modifications will be distributed. Technical support for District 2 should be directed to Lori Belz, CPESC, ( ) It is important to specify to the best of your ability the appropriate seed, fertilizer, mulch, blanket and other stabilization materials, as it is key to controlling erosion. Specifying the proper material will also result in cost savings during construction. Below is a general guide for design purposes. Topsoil It is important to retain all available topsoil on the project to the maximum extent practicable. It is ideal to place 6 inches of topsoil in areas to be seeded; however, this will have to be adjusted to the amount of available topsoil. If there is a shortage of available topsoil, plastic subsoils or organic and muck soils (up to 20% organic matter) can be mixed with granular subsoils at a ratio of 1 part plastic, organic or muck to 2 parts granular subsoils to create a topsoil-like material. Soil Preparation (spec 2574) Subsoiling Designate areas that are not to be used for staging, or driving (eg. infiltration treatments, wetland soil edges, certain utilities). Storage areas for equipment, stockpiles, and materials (i.e. Precast Median Barriers), temporary haul and access roads must be decompacted before final turf establishment. Areas with proposed turf establishment provide subsoiling, pay item by the acre Soil Bed Preparation Provide this for all areas that will require turf establishment. Provide in the plans soil bed preparation, pay item on slopes flatter than 1:2 and Soil tracking, pay item on slopes 1:2 and steeper. Lime (3879) Lime is helpful in establishing vegetation in acidic type soils. Most acidic type soils will be found in the eastern half of District 2. Lime recommendations are typically based on soil test ph results. If soil tests indicate the ph is below 6.0 apply 2 tons/acre of agricultural lime on the project. An Equal Opportunity Employer

2 Fertilizer The four types are as follows; Type 1 is commercial, type 2 is phosphorus free, type 3 is slow release nitrogen, and type 4 is natural base. Generally the pay item will be Type 1, 2, 3, or 4 by the pound. The analysis and application rate will need to be taken care of in a note on the SEQ or in the tabulation sheet in the plans. One idea is shown below: TAB SHEET NO. ITEM NO. STATEMENT OF ESTIMATED QUANTITIES DESCRIPTION UNIT TOTAL ESTIMATED QUANTITIES A Fertilizer type 3 (1) Pound 500 A Fertilizer type 4 (2) Pound 250 (1) Fertilizer analysis , application rate 350 lbs per acre for seed areas Fertilizer analysis , application rate 175 lbs/ acre for sod areas (2) Fertilizer analysis , application rate 150 lbs /acre for seed areas If you have multiple analysis of the same type fertilizer it can further be broken down and shown in the tab sheets to break down the pound of each. Seeding The seed mixture will depend on location, functional outcome, climate, and soil type. See Attachment 1 for a general seed, fertilizer and mulch or blanket recommendation based on project type. Note that the seed mixes have changed in the new specifications. The new application rates are based on Pure Live Seed (PLS) and the seed mix number changes provide information about the use and content of the mix. This numbering system can be used to guide the user in choosing the right mix for a given project. The reason for this change is the migration to unified state seed mixes for all state agencies to use. See Current seeding manual for seed mix s for general guidance for seed mixture use and seed mix conversion tables from old MnDOT seed mixtures. 1. Temporary Seed Mixtures. All plans must provide a seed pay item for temporary seed. Pay item seed mixture (21-xxx or 22-xxx) Temporary seed will be installed by the broadcast or hydroseed method. Use temporary seed for contiguous areas larger than 2.0 acres. Use rapid stabilization methods for areas smaller than 2.0 acres areas near waters. The plan must indicate areas for Rapid Stabilization; quantities should include an estimate of multiple applications based on staging or phase of construction. These are for small critical areas, scattered over the project site. Use in Areas of Environmental sensitivity (AES) and may be noted on plan sheet as Site Management Plan Area. Alternatives to temporary seeding or Rapid Stabilization consider using temporary poly covering in areas adjacent to rivers, bridge abutments, and other steep slope. The contractor will be able to open and close this cover every day while completing the work. Include a pay item temporary poly covering. 2. Permanent Seed Mixtures. Seed mixtures for the area may have native grasses and forbs custom designed for the site and context. Seed mixtures for roadways adjacent to Federal and State Forest lands may have certain prairie species, but should not be considered a prairie restoration. Steep slopes with a north aspect will need a custom mixture dominated by shade tolerant cool season grasses.

3 All bridge abutments, engineered walls, and slope systems will use the turf mixes unless otherwise noted. All storm water pond edges and upland buffers will be seeded with native mixes. All wetland mitigation systems will be seeded with native plant mixes, and may require a custom blend, based on regulatory issues. Sod Sod should be used in areas where it can be maintained or necessary for instant erosion control. Areas where sod may be considered are residential or business lawns, in urban areas, and areas of concentrated flow where erosion is a concern. It is important to specify the correct type of sod (Lawn, Mineral, or Salt tolerant) for the area to be placed. Lawn sod is appropriate for residential business lawns; Mineral sod is appropriate for granular, sandy soils; Salt tolerant sod is appropriate for high traffic areas at boulevards, and medians where salt use is high. Stabilizing Covers Various types of stabilizing covers can accomplish the outcome desired with respect to establishing vegetation. As a designer, it is important to choose a cost effective approach that balances the degree of protection with the cost of the material. The majority of projects will have more than one type of stabilizing cover specified due to the varying conditions across a project. These conditions include the degree and length of slopes, ditch gradients, contributing watershed areas, soil types, and whether it is temporary or permanent. Mulch (Spec 3882) Mulch Type 1 with disk anchoring is generally used for slopes 1:3 or flatter. Mulch quantities should reflect permanent and temporary amounts with the amount of estimated temporary mulch noted. The estimated temporary mulch quantities will depend on the duration of exposed soil on the project. The NPDES require exposed slopes to be covered in a specific time frame when they are not being worked. Specify Type 7 or 8 with native plantings and Type 3 mulch in areas to be assured no weeds are brought in with the mulch. Blanket (Spec 3885) For specified blanket areas where there is concentrated flow or slopes 1:2 and steeper, it is highly encouraged to note on the plan that maintenance is included with the blanket. As per the NPDES permit, blanket needs to be placed around an inlet for energy dissipation. In all ditches place blanket 200 ft. up from where it outlets to a surface water. Category 00: For areas where netting and stitching would be a problem. Category 0: Seeded lawns that will be highly maintained. Category 1: Rapid degradable netting to be used in mowed areas such as one blanket width next to the shoulder, residential lawns, and park areas. This blanket can also be used in flat areas. NOT FOR CONCENTRATED FLOW AREAS. Category 2: Not recommended for use. Category 3: Under permanent seeding conditions, generally used for slopes 1:3 to 1:2; ditch bottoms with gradients 3% or less and flow velocities 6.5 ft/s and less; and concentrated flow areas such as edge drains. Specify Wood fiber ditch bottoms and other areas of concentrated flow. Also, blanketed areas next to DNR protected waters and certain streams should specify a natural net. When natural netting is specified it shall be noted in the SEQ or tabulation sheets. Category 4: Slopes 1:2 and steeper; ditch bottoms 4% and less with flow velocities less than 7 ft/s; and areas with higher volumes of concentrated flow such as bridge side or end slopes to take water from where the curb ends. Category 5: Typically used in stream bank restoration projects only. Due to the density of the coconut, it is difficult to establish seed underneath, therefore not recommended in normal ditch bottoms. Hydraulic Erosion Control Products (Spec 3884) Tackifiers Type Natural: Shoulder mulch tacking agent in accordance with G. Use over the crimped mulch as shoulder stabilization of straw mulches.

4 Hydraulic Matrix Type Hydraulic mulch: Temporary mulch applications:. Areas such as stockpiles and slopes that do not receive concentrated flow can be stabilized temporarily to meet NPDES permit requirements. Flat areas, such as lawns, can be mulched permanently. Every plan will have a quantity for temporary Mulch Type 1 or Hydraulic Matrix, Type Hydraulic Mulch. Use a multiplier of 3-5 times the permanent turf areas for each construction season. Hydraulic Matrix, Type Bonded Fiber Matrix: Inaccessible areas for permanent mulch cover. Also for soil burden on top of rock cuts. Not to be used in moist areas. Hydraulic Matrix, Type Fiber Reinforced Matrix; for long term cover for erosive soils, also for temporary over wintering conditions. This also can be used as an alternate to Blanket for permanent turf establishment in erosive mow areas, and adjacent to traffic lanes, except in ditches. Turf Reinforcement Mats (TRM) All TRM s are topsoil or compost/soil blend filled. The TRM should be designed based on bed shear, with the first 3 classes providing a range of bed shear stabilization between 2.1 and 10 lbs/ft2. Class 4 is for steep slope surface stabilization where high tensile strength is required. Pay items for the topsoil and blanket over the top are needed. If a TRM is called for in the plan, it will always be blanketed with an appropriate class of erosion control blanket (typically Cat 3B). Special installation details will be required in the plan that includes head and check trenching, overlap, and stapling, pin, rod or some other attachment details. Temporary Ditch bottoms Ditch bottoms comprised of Silty Sand type soils may need to be stabilized with a Category 3 Erosion Control Blanket. This is more effective that no blanket and ditch checks. Exposed ditch bottoms and side slopes connecting to waters of the state need a Category 3 blanket 200 feet up from where it outlets to a surface water. Prairie Passage Routes In 1993, the FHWA gave funding to departments of transportation in Minnesota, Iowa, Missouri, Kansas, Oklahoma and Texas to develop a prairie passage. The goal of the prairie passage is to protect native grasses and wildflowers along the roadside right-of-way; plant native grasses and wildflowers along the roadside right-of-way; and promote the awareness of prairie related natural and cultural resources. District 2 has five roads designed as part of the prairie passage: TH 32 from the junction of TH 34 north to the junction of TH 102; TH 102 from the junction of TH 32 northwest to Crookston; TH 75 from Crookston north to the Canadian border; TH 175 from the junction of TH 75 east to the junction of US 59, and US 59 from the junction of TH 175 north to the Canadian border. Projects constructed on these roads shall use native vegetation, specify native seed mixes and prairie mulch. Watering For areas where it is critical to obtain good turf cover water is important. For watering of Turf Reinforcement Mats, steep slopes, RSS walls, slopes adjacent to infiltration areas, and ponds. Provide Temporary Irrigation/water by special provision. Weed Control Noxious weeds as defined by Minnesota Department of Agriculture must be controlled. There are several species on the noxious weed list. Each County may have additional secondary listed weeds that must be controlled. Weed spraying and or mowing will be required prior to the seeding operation. This should be indicated in the construction & soils notes. Expect to specify in the plan areas of concern and quarantine soil zones. Noxious weed locations can be obtained by consulting with the TGS responsible for vegetation management in each maintenance subarea in District 2. Weed Spraying

5 When noxious weeds are known to be on the project the designer should provide for weed spraying and weed spray mixture. Provide in the plans and tabulations the areas of weeds, weed type, herbicide, and either spot spray or broadcast spray. Contact OES Roadside Vegetation management Unit to obtain Herbicide recommendations. Provide the following note in the tabulations: Weed spraying to be done throughout the project to prevent and control spread of weeds. Weed spraying will be measured by the area covered or area spot sprayed by herbicide and successfully applied as indicated by dead noxious weeds. Weed spray mixture will be measured by volume of ingredients furnished and used. Mowing Provide mowing in plans, pay item by the acre. Include mowing in the provisions or plans according to the following schedule (to the extent possible within the timeframe of the project): Mowing to be done after the seeding and starting when the majority of vegetation is high. Mow non-native seeding once to control weeds. Mow native seeding approximately 3 times at 1-month intervals in the first growing season after planting, and 2 times at 1-month intervals in the second growing season. Attachments (2): Turf Establishment Recommendations

6 ATTACHMENT 1: Turf Establishment Recommendations Non-Native Desired Seed: 59 lbs/ac. Next to agricultural areas @ 45 lbs/ac. Fertilizer: Type 1, 250 lbs/ac Mulch: Type 2 tons/ac + Disc anchoring on all slopes flatter than 1:3. Blanket: Category 3 (slopes 1:3 to 1:2), category 4 on slopes 1:2 and steeper. Also ditch bottoms greater than 2%. GRADING/RECONSTRUCTION - RURAL AREA Native Desired Seed: D2 West: 36.5 lbs/ac On Sandy soils: 36.5 lbs/ac D2 East: 33.5 lbs/acre *Fertilizer: Type 4, 150lbs/acre, or Mulch: Type 2 tons/ac + Disc anchoring on all slopes flatter than 1:3. Blanket: Category 3 (slopes 1:3 to 1:2), Category 4 (slopes 1:2 and steeper). Specify Wood fiber on all ditch bottoms- category 3B. Temporary Seed: Up to 1 year; , @100lbs/acre, 1 to lbs/ac Temporary Fertilizer: Type 1, 200 lbs/acre, Temporary Mulch: Type 2 tons/ac + Disc anchoring; OR Hydraulic Matrix Type, Hydraulic Mulch Temporary Seed: Up to 1 year; 110 lbs/acre 1 to 5 years; @38 lbs/acre Temporary Fertilizer Type 1, 200 lbs/acre, Temporary Mulch: Type 2 tons/ac + Disc anchoring; OR Hydraulic Matrix Type, Hydraulic Mulch GRADING/RECONSTRUCTION - URBANIZED AREA Seed: 120 lbs/ac (adjacent to homeowners 220lb/ac adjacent to commercial businesses Fertilizer: Type 1, 250 lbs/ac Mulch: Category 1 blanket or Type 3 2 tons/acre + Disc anchoring Alternative: Sod with Type 1 fertilizer 175 lbs/ac TEMPORARY BYPASS Seed: 30.5 lbs/ac (44.8 kg/ha) Fertilizer: Type 1, 200 lbs/ac Mulch: Type 2 tons/acre + Disc anchoring or Hydraulic matrix type Hydraulic Mulch Bridge End and Side Slopes Seed: 59 lbs/ac Fertilizer: Type 1, 250 lbs/ac; OR Type 3, at 200 lbs/ac next to rivers and streams Blanket: Category 3 or 4 depending on steepness and slope length (include maintenance) BRIDGE REPLACEMENT Native Seed Mix Option: See Wet Ponds or Dry (Infiltration) Ponds Temporary Seed: (depending on length of time needed for embankment settlement) Up to 1 year; lbs/acre, Up to 2 years; 30.5 lbs/acre, Up to 5 years 40 lbs/acre Temporary Fertilizer: Type 1, @200 lbs/acre Temporary Blanket: Category 3(wood fiber) or Category 4 depending on steepness and slope length Temporary Seed: (depending on length of time needed for embankment settlement) Up to 1 year 110 lbs/acre, Up to 2 years; 38 lbs/acre Temporary Fertilizer: Type 1, @200 lbs/acre Temporary Blanket: Category 3(wood fiber) or Category 4 depending on steepness and slope length Temporary Mulch: Type 2 tons/ac + Disc

7 Temporary Mulch: Type 2 tons/ac + Disc anchoring; OR Type 4; OR Hydraulic matrix type hydraulic mulch anchoring; OR Type 4; OR Hydraulic matrix type hydraulic mulch MILL AND OVERLAY (Minimal Disturbance) Seed: 61 lbs/ac Fertilizer: Type 1, 250 lbs/ac Mulch/HECP: Type 4 or Hydraulic Matrix Type Fiber Reinforced SHOULDER WIDENING AND TURN LANES (With Inslope Regraded) Existing Native Non-Native Existing Seed: 59 lbs/ac Fertilizer: Type 3, 350 lbs/ac Mulch: Type 2 tons/ac + Disc anchoring or Type 4 Blanket: Category 3 ( slopes 1:3-1:2) Seed: @ 59lbs/ac Fertilizer: Type 3, 350 lbs/ac OR type 3, @ 200 lbs/ac next to rivers and streams Blanket: Category 3 or category 4 Alternative: Salt tolerant Sod, fertilizer Type 3, 200 lbs/ac Seed: D2 West: 36.5 lbs/ac D2 East: 33.5 lbs/acre *Fertilizer: Type 4, 150lbs/acre, or Mulch: Type 2 tons/ac + Disc anchoring Blanket: Category 3 ( slopes 1:3-1:2) CULVERT REPAIRS Native Seed Mix Option: See Wet Ponds or Dry (Infiltration) Ponds WET PONDS Do NOT seed bottom of pond Seed 1: D2 West: 35 lbs/ac D2 East: 35 lbs/acre to be planted 10 feet on either side of the normal water level *Fertilizer 1: Type 4, 120 lbs/acre, or Seed 2: D2 West: 36.5 lbs/ac D2 East: 33.5 lbs/acre to be planted from within 3ft of bottom to top of pond *Fertilizer 2: Type 4, 100 lbs/acre, or Mulch: Type 2 tons/ac + Disc anchoring Blanket: One blanket width (6-8feet, natural nettings) at the normal water level; emergency spillway; and areas of concentrated in-flow DRY (INFILTRATION) PONDS Seed 1: D2 West: 35 lbs/ac D2 East: 35 lbs/acre to be planted in the bottom and up 3 feet from the bottom *Fertilizer 1: Type 4, 120 lbs/acre, or Seed 2: D2 West: 36.5 lbs/ac

8 D2 East: 33.5 lbs/acre to be planted from within 3ft of the bottom to top of pond *Fertilizer 2: Type 4, 180 lbs/acre, or Mulch: Type 2 tons/ac + Disc anchoring Blanket: Areas of concentrated flow, such as pond corners or areas where ditches carry water into the pond. SIGNALIZATION Seed: @ 59 lbs/ac (78.3 kg/ha) Fertilizer: Type 3, 350 lbs/ac Blanket: Category 1; Category 3 at corners of concentrated flow PRAIRIE PASSAGE ROUTES TH 32 from the junction of TH 34 north to the junction of TH 102; TH 102 from the junction of TH 32 northwest to Crookston; TH 75 from Crookston north to the Canadian border; TH 175 from the junction of TH 75 east to the junction of US 59, and US 59 from the junction of TH 175 north to the Canadian border. Seed: 36.5 lbs/ac On Sandy soils: 36.5 lbs/ac Fertilizer: Type 4, or @150lbs/acre Mulch: Type 2 tons/ac + Disc anchoring on all slopes less than 1:. Blanket: Category 3(slopes 1:3 to 1:2) or 4 on slopes 1:2 and steeper. Also ditch bottoms greater than 2%. * (NPK) is to be specified in loam and clay loam (NPK) is to be specified in sandy soils with low clay and organic matter.